9. exposure assessment
TRANSCRIPT
RAPPORT SUR LA SECURITE CHIMIQUE
21
9. EXPOSURE ASSESSMENT
9.1. Introduction
Nexter Group is a French industrial armaments group. It manufactures military
equipments for ground combat, air-land, naval and naval air. Nexter Mechanics
(NMe) is an entity of the Nexter Group Company. It is the applicant for the Use-1, 2 &
3 of this authorisation dossier. NMe is a downstream user of chromic acids
generated from chromium trioxide.
The substance is contained in two types of mixture, one for black chromium
plating (liquid form), the other one for hard chromium plating (solid form). Use of
the substance is made in the same dedicated room, located on the site of Tulle in
France. Armament parts are treated by immersion in bath treatment. This
information is summarised in Table 7.
Legal entity Site location
(in France)
Number of workers
involved
Nexter Mechanics (NMe)
Tulle 5
Table 7: Nexter Systems & Nexter Mechanics AfA for the Use-4
Exposure assessment (and related risk characterisation) is focused on the use of
hexavalent chromium.
9.1.1. Overview of uses and Exposure Scenarios
For the sake of clarity, it is reminded that this document is part of a broader
AfA. Nexter’s authorisation is indeed composed of four uses that are described
below.
Titles of identified uses Titles of Exposure Scenarios site
Use-1: Industrial use of a mixture of chromium trioxide for the hard chromium plating of military armament steels parts which are thermomechanically stressed and in contact with oxidizing gas at high temperature, so as to ensure a thermal barrier with high melting point, resistance to wear and oxidation associated with weapons as well as resistance to impact and atmospheric corrosion.
ES-1: Industrial use of chromic acids mixture for chromium plating.
Tulle - NMe
Use-2: Industrial use of a mixture of chromium trioxide for the hard chromium plating of military armament parts in order to ensure surface hardness, resistance to atmospheric corrosion, abrasive wear resistance and friction coefficient for parts in relative movement.
Use-3: Industrial use of a mixture of chromium trioxide for the black colour hard chromium plating of exterior surface of steel weapon barrel designed for military use, to ensure, during the whole gun barrel service life, stealth, erosion, corrosion and high temperature resistances in the condition of uses.
Tulle - NMe
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Use-4: Industrial use, of a qualified mixture of chromium trioxide by spraying or immersion, and of a qualified mixture of dichromium tris(chromate) by pen application, for the chromate conversion coating of welded mechanical structures of armoured vehicles and associated parts made of high mechanical properties aluminium alloys for military use, and requiring a maintained electrical conductivity after severe climatic environments, atmospheric corrosion resistance and paint adhesion.
Separate CSR for Use-4
ES1: Industrial use, by spraying, of a qualified mixture of chromic acids for chromate conversion coating.
Roanne - NeS
Separate CSR for Use-4
ES2: Industrial use, by immersion, of a qualified mixture of chromic acids for chromate conversion coating.
Tulle – NMe
Table 8: Identified uses and Exposure Scenarios
This CSR is focused on NMe application and covers Uses-1, 2 & 3. Please note
that Uses-1, 2 & 3 are performed on only one site at Tulle. This site is completely
independent from the Roanne site in terms of operators concerned and this CSR
concern only the site of Tulle.
Nevertheless, operations related to Uses-1, 2 & 3 that take place on the Tulle site
create combined exposures. These operations are sampling and titration (CS-2 & 3 of
the ES-1 of this CSR). They are combined with the exposure generated from the
Use-4, detailed in a separate CSR in ES-1, as regards Contributing Scenarios 2
(sampling) and 3 (titration) only. The combined exposures of these Contributing
Scenarios are taken into account in the section 10 of both CSR.
The rest of the operations for Uses-1, 2 & 3 in Tulle being independent from Use-4
are addressed in this CSR.
9.1.1.1. Process explanation
This CSR will discuss the use of chromic acids for the hard and black
chromium plating of military armament steels parts. The process for hard chromium
plating and black chromium plating are very similar in terms of operating conditions,
risk management measures, exposures and workers involved in the operations.
Consequently, the process for both hard and black chromium plating are described in
the same exposure scenario. The duration of tasks and involvement of operators will
then be specifically described for each uses (1, 2 & 3) in the section 10 of this CSR.
Except the titration of hexavalent chromium, all the operations relating to
the chromium plating take place in the same dedicated room.
Presentation of the workshop
In the plating shop, all the activities are performed by the same operators.
There are a maximum of 5 operators concerned by these tasks. An exact estimation
based on passed activity and prevision is provided in section 10 of this CSR. The
operators of the plating line are the same for both black chromium plating and hard
chromium plating.
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Armament parts are treated by dipping in baths treatment. The part is
attached to a hoist from the top so it can be totally immersed in the bath. A specific
area is dedicated to the assembling and dismantling of the armament part from the
hoist. Then, the operator remotely manipulates the part to immerse and pull them
out of the baths treatment with a remote control of the hoist.
Further operations are performed in the plating shop: the sampling of
chromium baths in order to control the hexavalent concentration and the addition of
hexavalent chromium into the baths treatment.
The assembling and dismantling, the addition of substance in baths and the
dipping and flushing of armament parts are the main tasks daily performed in this
working area. They represent a typical working day.
The worker location in the plating shop during the different Contributing
Scenarios (CS) are summarised in Figure 2.
Figure 2: Plating shop map and location of each activity
A photo of the plating shop is also presented below, in Figure 3.
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Figure 3: Photo of the plating shop
Sampling of bath and titration of hexavalent chromium
The bath composition is controlled with a weekly period. Sampling is
performed with a flask assembled on a rod. One sampling per week is performed on
each bath, which leads to a total of 4 samplings per week. It is done by one specific
operator who only carries out this task on the plating line and then performs the
titration of hexavalent chromium in the laboratory.
The sample is then brought into the lab for analysis. The analyses are
performed in order to control the baths composition and, if needed, adjust the
concentrations. The lab is a separate room from the plating shop. 12 analyses are
performed each week (9 for hard chromium baths and 3 for black chromium bath),
and 8 more analyses are performed each month (6 for hard chromium baths and 2
for black chromium bath), for a total of (12 x 44 + 12 x 8) analyses per year. When
the analyses are performed, the duration of possible exposure to hexavalent
chromium cannot exceed 3 minutes per analysis.
This task is considered in the estimation of exposure to hexavalent chromium. It is treated in this CSR in the Contributing Scenarios 2 & 3 (CS-2 & 3).
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Addition of hexavalent chromium in bath
The addition of hexavalent chromium into the baths can occurs in two
different contexts, after drain of tank as explained in the next paragraph, or just as a
supplement in the context of routine use:
- Addition after drain of tank: this addition does not exceed a pouring of
60 min.
- To supplement the routine use: According to the analyses results of the
sample taken, the tank bath is adjusted. In this context, this operation does
not exceed 30 min.
The substance can be added in the bath in a liquid form or a solid form,
depending of the type of chroming performed. The liquid form is the solution
supplied by Atotech, used for black chromium plating in only one bath treatment.
The solid form is the one supplied by A.M.P.E.R.E. Industrie, it is presented as pellets
and it is used for hard chromium plating in three baths.
The containment of the hexavalent chromium is handled for pouring the
substance into the bath treatment. The final concentration of hexavalent chromium
into the bath can vary but it cannot exceed 40% (w/w). It will be considered
substantial (in the range of 10 to 50% w/w).
The addition of solution regardless of the context is always performed with
the same operating conditions and the same risk management measures, except the
solid or liquid form of the solution. It is described in the contributing scenario 4 for
solid form, and in the contributing scenario 5 for the liquid form.
The only difference between the two types of additions is the duration and
frequencies of these activities.
This task is considered in the estimation of exposure to hexavalent chromium. It is treated in this CSR in the Contributing Scenarios 4 & 5 (CS-4 & 5).
Drain of bath
In case of technical problem concerning the bath composition, baths can be
partially washed out. This is not a normal operation. Based on the past operating
experience, the frequency of this task is estimated to be one drain of one chroming
tank every year for the whole plating shop.
In this case, one operator opens the outbound fluid valve. As with all the
operations performed in the plating shop, the worker wear protective clothes,
protective gloves and respiratory protective equipment. A dedicated settled sewer
system is used to collect the content of the bath and channel it to the waste
treatment plant. This operation does not involve direct manipulation of the
substance. Otherwise, indirect exposure via inhalation of the ambient air in the
plating shop can occur, due to the opened chromium baths of the plating shop.
Consequently, the exposure estimation will be treated in a specific contributing
scenario dedicated to the bath treatment as emission source in the workers’ far field
(CS-9).
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There is no possibility of direct exposure to hexavalent chromium during this task. Consequently it will not be treated in this CSR.
However, during this operation, the worker is located in the plating shop and indirect exposure via inhalation due to the chromium bath will be considered. This
activity is included in the Contributing Scenario 9 (CS-9).
Dipping armament parts in baths
During the manipulation of the armament part, the operator is located
behind the bath with the remote in one hand, so as to control the armament part
attached to the hoist and immerse it in the bath. During the immersion in the
chromium bath treatment, the part is connected to an anode, thereby inducing an
electric current which will allow the hexavalent chromium plating, forming a
chromium layer on the part. The control of the plating on specific location of the part
is the expertise of Nexter Mechanics. Depending on the type of armament part, a
maximum of 2 parts can be treated at the same time, in one bath treatment, during
one day.
Dipping in bath treatment for the complete chromium plating of one
armament part is variable and takes several hours. When the part is dipped, the
operator does not stay next to the bath and goes to do other activities.
In terms of potential exposure for workers, dipping an armament part in a
chromium bath treatment takes therefore approximately no more than a total
duration of 40 minutes. It takes into account the activities performed to both
immersion in the bath and pull-out the armament part (approximately 15 minutes
maximum), to connect the anodes to the immersed armament part (approximately
15 minutes maximum) and, if needed, for the adjustment of bath level (performed
by pressing a button located next to the bath in order to supplement the bath with
water, which takes 10 minutes maximum). Local exhaust ventilation is present on
each bath. All these operations are part of the same tasks performed at the bath
and they will be considered in the same contributing scenario (CS-6).
After control of the armament parts, if the chromium layer is not considered
acceptable, armament parts can be treated a second time after de-chroming
treatment. The de-chroming treatment is performed in a specific bath. Operating
conditions are also identical to the chrome plating treatment. The concentration of
the de-chroming bath is not exactly known and it will be considered equivalent of the
chromium bath treatment as a default value. Thus, this task will be considered in the
same contributing scenario (CS-6).
After rinsing the part with water jet (this activity is described in the following
section), armament parts are rinsed by dipping in two successive rinsing baths with
the remote control of the hoist. Operator manipulations are identical to the chrome
plating treatment. The only significant difference with the operation of dipping in
chromium treatment bath is the concentration of hexavalent chromium in rinsing
baths which is much lower. The duration taken into account for the dipping in the
two successive rinsing baths will be 30 minutes (2x15min). This task will be
considered in the contributing scenario 8 (CS-8).
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These tasks are considered in the estimation of exposure to hexavalent chromium. They are treated in this CSR in the Contributing Scenario 6 (CS-6) for the activity performed at the chromium baths treatment and de-chroming bath, and in the
Contributing Scenario 8 (CS-8) for the activity performed at the rinsing bath.
Flushing of the armament part
When the armament part is pulled out of the chromium bath treatment with
the hoist, the armament part is suspended above the bath and the operator briefly
rinses it with water jet. The water falls into the chromium bath. The duration of this
task is less than 2 minutes for each part.
This task is considered in the estimation of exposure to hexavalent chromium. It is treated in this CSR in the Contributing Scenario 7 (CS-7).
Assembling and dismantling armament parts
During the dipping in successive baths, some specific locations on the
armament part must be masked. Masking tapes are therefore applied to these areas.
The whole masked part is then clipped to a hoist, in order to facilitate the
manipulation of the armament part during dipping operations. Therefore at the
beginning and at the end of the treatment, operators need to clip and unclip the part
from the hoist and assemble and remove the masking tapes.
At the beginning of the operations, the part has not yet been in contact with
hexavalent chromium. Consequently, there is no possible exposure to hexavalent
chromium due to the handling of articles at this stage.
During the dismantling of armament parts from the hoist, i.e. after the
treatment in baths, the parts have been rinsed by water jet and by dipped in two
successive rinsing baths (containing water). Furthermore, during the treatment, the
hexavalent chromium is reduced in metallic chromium. Consequently, no hexavalent
chromium is present at the surface of the treated armament part. In any case,
workers who handle the armament part use protective gloves as a safety measure.
Thus, direct exposure via dermal route to hexavalent chromium due to the
handling of armament part during the assembling and dismantling on the hoist
cannot occur.
However, indirect exposure via inhalation of the ambient air in the plating
shop can occur, due to the opened chromium baths present in the plating shop.
Consequently, the exposure estimation will be treated in a specific contributing
scenario dedicated to the bath treatment as emission source in the workers’ far
field (CS-9).
There is no possibility of direct exposure to hexavalent chromium during this task. Consequently it will be not treated in this CSR.
However, indirect exposure via inhalation due to the chromium bath in the plating shop will be considered during this activity in the Contributing Scenario 9 (CS-9).
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Control of the armament parts
For armaments parts with specific areas for which visual control is not
possible, operators must do a borescope inspection. This inspection is performed
outside the working shop on a finished article. The chromium deposited on the
article is reduced in metallic form and the armament parts have been rinsed
successively with water jet and two rinsing baths. Consequently, there is no
possibility of exposure during the manipulation of the finished armament part,
including during this control of armament part.
There is no possibility of exposure during this task, consequently it is not considered in this CSR.
Maintenance operations
Maintenance operations that do not create any direct exposure to
hexavalent chromium can be performed in the plating shop. These operations
include the maintenance of pumps dedicated to the baths, storage of anodes or
maintenance of others installations located in the plating shop. These operations are
performed by the same workers involved in the rest of chroming activities in this
plating shop. Exposures via inhalation during these tasks are considered and included
in the contributing scenario 9 (CS-9).
There is no possibility of direct exposure to hexavalent chromium during this task. Consequently it will be not treated in this CSR.
However, indirect exposure via inhalation due to the chromium bath in the plating shop will be considered during this activity in the Contributing Scenario 9 (CS-9).
Cleaning of the waste collector pit
The centre of the plating shop is on an elevated duckboard. Under the
duckboard, there is a waste collector pit, used to collect possible drops from
activities done during the surface treatment. The pit is cleaned twice a year, during
approximately two hours by one operator. When an operator cleans the pit, he is
wearing acid resistant protective clothing, boots, gloves and goggles. The operator
first waters the ground with a water jet, and then goes down in the pit and sweeps
the floor to guide the water to the pumping collection system. The waste water
collected from the pit is treated on site.
It has to be stressed that hexavalent chromium is a strong oxidising agent
and can react with a wide range of reducing agents to form trivalent chromium. Even
if the potential reducing agents capable of reacting and present in the waste
collector pit are not known, it can be stated that reduction reactions of hexavalent
chromium occurs. As presented in different official reports (INERIS; EU RAR), most of
known reactions are rapid reduction to chromium (III). Consequently, possible drops
or spatters falling through the duckboard in the waste collector pit and which
contains hexavalent chromium should be mostly reduced. Thus, when an operator
sweeps the water floor during this cleaning operation, the concentration of diluted
remaining hexavalent chromium in this water is considered extremely small (0.1 to
CHEMICAL SAFETY REPORT
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0.5%) which correspond to the realistic worst case. However, there is still a potential
for exposure to hexavalent chromium that is analysed in the contributing
scenario 10.
This task is considered in the estimation of exposure to hexavalent chromium. It is treated in this CSR in the Contributing Scenario 10 (CS-10).
Waste treatment plant
The waste treatment plant (WTP) on the site of Tulle is an installation with no
liquid effluent which permits to treat the used mixture which contains hexavalent
chromium and to recycle the water contaminated by producing demineralised water.
All the baths containing hexavalent chromium are treated with the same
process in the WTP dedicated to the used chromium mixtures. This includes the
liquid effluents from chromating baths, and liquid effluents from rinsing baths
(contaminated by hexavalent chromium).
Baths effluents are collected in a dedicated container in the WTP wherein it
will be performed a dechromating process (with sodium bisulfite). During this
operation, hexavalent chromium is reduced in trivalent chromium. Then, it is
performed a neutralisation with soda and flocculation followed by filtration on filter
press. Sludge produced is disposed of to a specialized centre. The distillate produced
is channelled to the treatment line for demineralized water which uses active
carbon.
This step on the process is considered in the estimation of environmental exposure to hexavalent chromium. It is treated in this CSR in the Contributing Scenario 1 (CS-
1).
9.1.1.1.1. Tasks to be considered in the CSR
Based on the foregoing description of the process, the exposure scenario will be
described with one contributing scenario dedicated to the environmental
consideration and the following tasks:
Exposure scenario 1 (ES1), Industrial use of chromic acids mixture for
chromium plating:
o Sampling of bath
o Titration of the hexavalent chromium
o Addition of liquid mixture to the bath
o Addition of solid substance to the bath
o Dipping armament parts in baths treatment
o Flushing of the armament part
o Dipping armament parts in rinsing baths
o Dipping armament parts in baths treatment, in the worker’s far field
o Cleaning of the waste collector pit
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9.1.1.2. Tonnage information / Number of worker exposed:
Tonnage information
Above quantities are based on estimations for the maximum amount used
for hard chromium plating and black chromium plating to cover the activities
considered during the review period. To make this estimation, the applicant used the
figures of the past years (2012, 2013 and 2014), i.e. the number of tubes treated, the
quantities of chromium trioxide used and the prevision of possible activities during
the review period.
Hence, over the review period, the maximum quantity used is estimated at:
- 0.5 ton per year for hard chromium plating,
- 0.3 ton per year for black chromium plating.
Consequently, the total tonnage of substance considered in this CSR is 0.8 ton per
year.
A precision should be given for this assessment. The detailed assessment of the
quantities involved beyond the sunset date is related to defence contracts that are
still confidential and will not be disclosed, even internally at Nexter, before the
submission of this dossier. Consequently, the realistic quantities which can be used
considering the maximum capacity of production in the plating shop and the past
activities were considered for this assessment.
Number of people exposed
Except for the sampling and titration (CS 2 & 3), the activities described in
Exposure Scenario 1 are all implemented in the same workshop. A maximum of 5
workers in the plating shop and one more for the sampling and titration are
concerned. In the plating shop, they conduct the same activities. Activities are
divided in two half-days. 2 or 3 workers operate in the morning and 1 or 2 workers in
the afternoon. 1 specific worker performs samples and analysis.
Hence, depending on the purchase orders, the total number of workers is either 4
or 5.
9.1.1.3. Overview of exposure scenarios
The following table lists all the exposure scenarios (ES) assessed in this CSR.
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Identifiers* Market
Sector
Titles of exposure scenarios and the related contributing
scenarios
Tonnage of
chromium
trioxide (tonnes
per year)
IW-1
d
SU 3
PC 14
ES1- Industrial use of chromic acids mixture for chromium plating
0.8
IW-1.1 - Industrial use resulting in inclusion onto a matrix (ERC 5)
IW-1.2 - Sampling of bath (PROC 8a)
IW-1.3 - Titration of the hexavalent chromium (PROC 15)
IW-1.4 - Addition of liquid hexavalent chromium in bath (PROC 8a)
IW-1.5 - Addition of solid hexavalent chromium in bath (PROC 8a)
IW-1.6 - Dipping armament parts in baths treatment (PROC 13)
IW-1.7 - Flushing of the armament part (PROC 8a)
IW-1.8 - Dipping armament parts in rinsing baths (PROC 13)
IW-1.9 - Dipping armament parts in baths treatment, in the workers’ far
field (PROC 13)
IW-1.10 - Cleaning of the waste collector pit (PROC 10)
* IW = Industrial end use at site.
Table 9: Overview of exposure scenarios and contributing scenarios
9.1.2. Introduction to the assessment
9.1.2.1. Environment
The environmental assessment is not the main consideration for this CSR
dedicated to the Application for Authorisation regarding the SVHC properties stated
in column 2 of entry 16 in annex XIV of REACh (COMMISSION REGULATION (EU) No
125/2012).
At the end of the process all wastes are managed by a specialised waste
management company that also collects all the wastes (liquid, paper, PPE…).
Nevertheless, in the environmental contributing scenarios, applicant will analyse and
discuss the possible release and risk for the general population.
9.1.2.2. Man via environment
Risk analysis for man via environment will be performed according to the
conclusions of the environmental release identified in the environment.
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9.1.2.3. Workers
The excess risk calculation will be based on RAC/27/2013/06 Rev.1 which
establishes a reference dose response relationship for carcinogenicity of
hexavalent chromium.
Regarding the publication of the RAC, no data clearly indicate that dermal exposure
to Cr(VI) compounds presents a risk of cancer to human. Furthermore, NIOSH8
reports that some data indicates that CrVI is reduced prior to systemic uptake
(Corbett GE et al. 1997 ; Liu KJ et al. 1997). As a consequence, the risk induced via
dermal exposure will not be considered in what follows, especially taking into
account the potential dermal exposure previously presented are considered
negligible.
Moreover, and since the form of the substance is mainly liquid, we will estimate
the cancer risk due to volatility of the substance, for lung cancer, and maximize
excess of cancer risk by not taking into account the small intestine cancer risk.
Monitoring measurement campaign is planned on an annual basis on each site for
exposure assessment of the entire process. For the description of each contributing
scenario, we will use the ART 1.5 software to calculate an associated value of
exposure. In the modelling process, we will use the Long-term value at 90th
percentile for the entire contributing scenario. ART modelling reports are given in
Annex II. Nevertheless, to calculate the excess risk of cancer (Chapter 10) we will use
the combination of estimation and monitoring value to assess a quantitative analysis.
In France, as of July 2014, the regulatory constraining level is fixed at 1 µg/m3.
Companies are obliged to carry out air working measurement and take adequate risk
management measures in order to ensure that exposures are below the regulatory
level.
Considering reprotoxic effects, as mentioned in section 5, this Chemical Safety
Report focuses on the use of hexavalent chromium for the carcinogenic/mutagenic
effects. The low level of exposure demonstrate in the following sections of this CSR
to assess the risk due to non-threshold effects (cancer) will cover risk due to
threshold effects for reproduction. Moreover, when threshold effects are adequately
controlled, they must not be taken into account in the excess risk calculation.
Thus, exposures and excess risk calculation will be developed considering only
carcinogenic effects.
9.1.2.4. Consumers
Not relevant since no consumer will use the final manufactured articles because they
are military equipment and they are not intended to be used by consumers.
8 National Institute for Occupational Safety and Health, Occupational Safety and Health
Administration Request for information Occupational Exposure to Hexavalent Chromium (CrVI); Novermber 20, 2002.
CHEMICAL SAFETY REPORT
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Only professional workers use the treated armament parts, but these armament
parts do not contain any hexavalent chromium anymore since the chromium plating
is a reduction of the hexavalent chromium to metallic chromium on the surface of
the article. Consequently, there is no possibility of exposure for professional workers
using the finished article.
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9.2. Exposure Scenario 1 (ES1): Industrial use of chromic
acids mixture for chromium plating.
Sector of use:
Industrial use: Uses of substances as such or in preparations at industrial sites (SU 3)
Article category:
Metal articles (AC 7)
Environmental contributing scenario:
Industrial use resulting in inclusion onto a matrix (ERC 5)
Worker contributing scenarios:
- Sampling of bath (PROC 8a)
- Titration of the hexavalent chromium (PROC 15)
- Addition of liquid hexavalent chromium in bath (PROC 8a)
- Addition of solid hexavalent chromium in bath (PROC 8a)
- Dipping armament parts in baths treatment (PROC 13)
- Flushing of the armament part (PROC 8a)
- Dipping armament parts in rinsing baths (PROC 13)
- Dipping armament parts in baths treatment, in the workers’ far field (PROC 13)
- Cleaning of the waste collector pit (PROC 10)
The exposure scenario concerns the use of chromic acids for chromium
plating. Only the tasks which lead to exposure of hexavalent chromium, as identified
in the section 9.1.1 are analysed as contributing scenarios.
Efficiency of respiratory protective equipment
In any case, when a worker is in the plating shop, wearing respiratory
protective equipment (RPE) is mandatory. Thus, to estimate exposure at the
workplace, it is necessary to determine the effectiveness of the respiratory
protection. It results in the assigned protection factor (APF). The choice of this factor
may vary, depending on the country for which it is used. Table 10 presents the
various protective factors assigned to the breathing equipment used in this exposure
scenario. It is a half mask which has been tested to European Standard EN 143 and
has met the relevant requirements of the category P3.
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Country /
Nominal protection factor
Assigned
protection
factor (APF)
France (advised by INRS19
) 10
Germany 30
Italy 30
United Kingdom 20
Nominal protection factor 48
APF used in this CSR 10
APF presented in annex C of the NF EN 529 standard and in INRS guidance
9
Table 10: assigned protection factor
The applicant made the choice to use an APF of 10. This tie in with a
precautionary approach and with the methodology of the modelling approaches of
MEASE10, recommended in the technical guidance of ECHA (ECHA 201211).
9 INRS (Institut National de Recherche et de Sécurité). Les appareils de protection
respiratoire, choix et utilisation. 2011. Ref : ED 6106 10
MEASE is a modelling tool for exposure estimation at the workplace. As described in the section 9.1.2.3, the modelling approach of this CSR, is based on the ART Tool for Tier 2 exposure estimation. MEASE is not used because it is Tier 1 exposure estimation. However, the present version of ART cannot estimate the exposure with respiratory protective equipment and consequently the applicant needs to determine an assigned protection factor.
11 Guidance on information requirements and chemical safety assessment, Chapter R.14:
Occupational exposure estimation. Version: 2.1. 2012. Paragraphe R.14.4.8.3 page25.
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9.2.1. Environmental contributing scenario 1: Industrial use resulting in
inclusion onto a matrix
9.2.1.1. Conditions of use
Parameter Information
Product characteristics
• Product Hexavalent chromium in a mixture.
• Physical form Liquid
• Amount 0.8 t / an
• Weight fraction of
the substance in the
liquid mixture
Concentration of substance in a bath is in the range of 10 to 50 % (w/w)
Operational conditions
• Emission Sources
Process is a closed system for which no release is expected except for:
- Air extraction from the baths treatment
- Waste production during the treatment of liquid effluents
The integrity of the process is regularly monitored.
The possibilities of release are detailed below.
• Atmospheric
emissions
Air from local extraction of the baths in the plating shop is collected through a specific system and treated via a mist eliminator. The air is then evacuated through a chimney on the roof of the plating shop.
The possible atmospheric emissions will be considered in the following part of the CSR.
• Liquid effluents
All the liquid effluents containing chromic acids on the site of Tulle (including baths treatment described in the other CSR for the use-4) are collected in specific wastewater pipe and treated with a specific treatment in the waste treatment plant (WTP) of the site.
Water used in the two rinsing baths is recycled by using a treatment with active carbon. This treatment produced demineralized water. Chromium is consequently eliminated from water.
Mixture drained from the used baths treatment is collected and treated with a specific process. Hexavalent chromium is reduced with soda. Then it is performed a flocculation, followed by a filtration on filter. The water produced with this process is then recycled to produce demineralised water through the process with active carbon described above.
With this treatment, there is no liquid effluent from the immersing process.
• Waste production All the waste (sludge and used materials) produced during these treatments are managed by a specialized certified waste company.
Table 11: condition of use for the contributing scenario 1
CHEMICAL SAFETY REPORT
37
9.2.1.2. Releases
Considering the data presented in Table 11, only atmospheric release could
be considered.
In a different official report regarding possible exposure to hexavalent chromium12,13,
experts considered that the possible risk stems from the local air compartment.
Indeed, on water and soil, the hexavalent chromium is transformed into trivalent
chromium via redox reaction13,14.
Moreover, the EU RAR about hexavalent chromium compounds’ the release during
metal treatment, did not consider the air release (except during formulation of
products)12.
Because no release measurement is available, the applicant estimates the release
based on modelling exposure. The technical guidance document part II15 propose
estimated release factor depending on the activity type.
The associated release factor is determined by the following parameters:
o IC 16 (Industrial category: engineering industry),
o Solubility > 1g/L,
o Vapour pressure <10 Pa,
o MC=3 (Main category: Non-dispersive use)
For the site of Tulle, the release factor is determined at 0.00001
Based on this release estimation and the Doury abacus16 (which estimates the
dispersion speed), the applicant calculated the exposure of the general population
around the site and the associate risk.
Release per working day is estimated (considering 200 working days per year):
= 36.36 mg per day
Release per day: 36.36 mg/day (0.42 µg/s)
The worst case (combined for each site), was taken for the assessment, with the
nearest house at approximately 100m and located in a non-urban area.
Atmospheric transfer coefficient (at 100m) from Doury Abacus: 1.87x10-3 s/m3
12 European Union Risk Assessment Report on hexavalent chromium substances (Volume
53 3rd
priority list) 13
INERIS - Fiche de données toxicologiques et environnementales du chrome et de ses dérivés
14 EPA Ground Water Issue, Natural Attenuation of Hexavalent Chromium in
Groundwater and Soils, EPA154015-941505, 1994 15
Technical Guidance Document on risk assessment, part II about environmental risk assessment
16 Abaques d'evaluation directe des transferts atmospheriques d’effluents gazeux, Doury
et al, February 1980
CHEMICAL SAFETY REPORT
38
The release in air adjusted on 24h is:
Release
(0.42 µg/s) X
Atmospheric transfer coefficient (at 100m) from
Doury Abacus (1.87x10-3
s/m3)
= 7.87 x 10-4
µg/m3
9.2.1.3. Exposure and risks for the environment and man via the environment
As described above, release of chromium trioxide in the environment are
negligible. No exposure to the substance of man via environment is therefore
considered in this exposure scenario and for these compartments.
Regarding the release in the atmospheric compartment, after calculation, the
exposure for general population is 7.87 x 10-4 µg/m3 per 24h and 220 working days.
As a normal year counts 365 days, the adjusted exposure is 4.74x10-4 µg/m3.
Workers use the substance indifferently for the Use-1 & the Use-2 (hard
chromium plating), and in a separate manner for the Use-3 (black chromium plating).
Hence, the general population exposure will be adjusted for the Uses-1&2 on the
one hand, and for the Use-3 on the other hand, by considering that:
- 0.5 tons per year are involved in the Uses 1&2,
- 0.3 tons per year are involved in the Use-3.
Consequently the exposures are presented in the following table:
Use-1&2 general population adjusted
exposure (µg/m3)
(For Hard chromium plating)
Use-3 general population adjusted
exposure (µg/m3)
(For Black chromium plating)
Total general population exposure
(µg/m3)
2.96x10-4 1.78x10-4 4.74x10-4
Table 12. General population adjusted exposure by Use
The excess of risk of lung cancer for the general population will be adjusted to the
review period for the Use-1 (12 years) and the Uses-2&3 (7 years).
CHEMICAL SAFETY REPORT
39
Weighted excess of lung cancer risk for general
population Value
Excess risk of lung cancer, per µg/m3 of Cr(VI)
based on 70 years, 365 days per year, 24h per
day (RAC 2013) 2.9x10-2
Excess risk of lung cancer, per µg/m3 of Cr(VI)
based on 1 year, 365 days per year, 24h per day 4.1x10-4
Excess risk of lung cancer, per µg/m3 of Cr(VI)
based on 7 years (review period for the Use-4),
365 days per year, 24h per day 2.9x10-3
Excess risk of lung cancer, per µg/m3 of Cr(VI)
based on 12 years (review period for the Use
2), 365 days per year, 24h per day 4.97x10-3
Table 13. RAC adjusted excess of risk calculation for general population
Taking into account the exposure for both Use1&2, and for Use 2, the final excess
risk for each uses are presented in the following table:
Excess risk Value
Final individual excess risk of lung
cancer based on 12 years (review
period for the Use-4), 365 days per
year, 24h per day for the Use-1
1.47x10-6
Final individual excess risk of lung
cancer based on 7 years (review
period for the Use-4), 365 days per
year, 24h per day for the Use-2
8.60x10-7
Final individual excess risk of lung
cancer based on 7 years (review
period for the Use-4), 365 days per
year, 24h per day for the Use-3
5.16x10-7
Table 14. Risk calculation by Use for general population
It could be noted that the exposure due to Use-1 or Use-2 cannot be assessed
separately. Consequently, the exposure for both uses was double counted because it
used twice in the excess risk calculation (despite the fact that this excess risk was
calculated for the Use-1 and for the Use-2 separately. This is judged as an over
estimation of the risk.
CHEMICAL SAFETY REPORT
40
Conclusion:
Compare to the worker’s excess risk of lung cancer
Considering the amount of substance use at the working place
Considering that in this generic approach the exposure due to Use1&2 are double
counted
Considering the risk management measure implemented by Nexter
Considering the hexavalent chromium atmospheric release by working days
Considering that the decision point for “acceptable” lifetime cancer risk levels used
for workers are generally around 10-5 *
The risk for general population is considered as negligible.
* This decision point is presented in the technical guidance of ECHA17
17 ECHA Guidance on information requirements and chemical safety assessment, chapter
R8, Appendix R. 8-14 page 141.
CHEMICAL SAFETY REPORT
41
9.2.2. Worker contributing scenario 2: Sampling of bath
This contributing scenario deals with the exposure of workers during the
sampling of the mixture containing hexavalent chromium in the bath treatment, as
described in paragraph 9.1.1.1.
9.2.2.1. Conditions of use
In this contributing scenario, exposure is estimated with the modelling approach of
ART (Advanced REACh Tool) version 1.5. The conditions of use described in the Table
15 present the information required for this estimation.
Parameters Condition of use on the
Nexter’s site Information for modelling
Product characteristic
• Product Mixture containing hexavalent
chromium in baths treatment Mixture
• Physical form Chromium trioxide dissolved in a
liquid mixture. Powder dissolved in a liquid
matrix
• Weight fraction
The weight fraction of hexavalent chromium compound can vary but it cannot exceed 40%.
Substantial (10-50%)
• Viscosity low viscosity (like water) low viscosity (like water)
Operating condition
• Activity class Sampling of bath by transferring
the mixture in a vessel.
Transfer of liquid products.
Falling liquids.
• Loading type
Sampling is performed with a flask assembled on a rod, which is dipped in the bath.
Submerged loading (where the amount of aerosol formation is reduced).
• Flow of transfer Less than 100ml in 2 minute <0.1l/minute
• Duration 2min 2min
• Primary emission source proximity
At arm's length. <1m
Risk management measures
• General ventilation Only good natural ventilation Only good natural ventilation
• General control Measures Fixed capturing hood Fixed capturing hood
• Level of containment Open process Open process
• Demonstrable and effective housekeeping practices in place
No No
• General housekeeping practices in place
Yes Yes
• Work area Indoors Indoors
• Size of the work area Approximately 800m3
Large workrooms only (300 to 3000m
3)
Version of the modelling tool : ART (Advanced REACh Tool) version 1.5
Table 15: Condition of use of the contributing scenario 2 - modelling
CHEMICAL SAFETY REPORT
42
The ART modelling tool does not take into account all the necessary information for
the risk assessment as required in the CSR. Table 16 presents the necessary
information that does not affect the modelling results.
Parameters Information
Personal protective equipment
• Respiratory protective
equipment (RPE) Half mask category P3 (EN 143)
• Other personal protective
equipment Protective gloves (chemical gloves approved according to EN 374) and Protective clothes. Technical data sheet in annex.
Other parameters
• Quantity Less than 100ml per operation
• Number of workers 1 per operation ; 1 operator involved
• Frequency 4 sampling per week
Exposure value will be validated by working air measure campaign (monitoring). Level of exposure lower than
the estimated level will confirm the risk assessment performed in this CSR.
Table 16: Condition of use for the contributing scenario 2 - other conditions
9.2.2.2. Exposure and risks for workers
The estimated exposure for this contributing scenario is presented in the Table
17. The exposures are presented with and without respiratory protective equipment
(RPE). The description of the RPE used is given at the beginning of the section 9.2.
Type of exposure Exposure concentration
estimation Duration of work
Raw exposure, ART estimation -
Without RPE 0.87 µg/m
3 2 min
Raw exposure, ART estimation -
With RPE 0.087 µg/m
3 2 min
Table 17: Exposure estimation - contributing scenario 2
CHEMICAL SAFETY REPORT
43
9.2.3. Worker contributing scenario 3: Titration of the hexavalent
chromium
This contributing scenario deals with the exposure of workers during the
titration of the mixture containing hexavalent chromium, performed on a laboratory
bench, in a dedicated local separated from the plating shop, as described in
paragraph 9.1.1.1.
9.2.3.1. Conditions of use
In this contributing scenario, exposure is estimated with the modelling approach of
ART (Advanced REACh Tool) version 1.5. The conditions of use described in Table 18
presents the information required for this estimation.
Parameters Condition of use on the
Nexter’s site Information for modelling
Product characteristics
• Product Mixture containing hexavalent
chromium Mixture
• Physical form Chromium trioxide dissolved in a
liquid mixture Powder dissolved in a liquid
matrix
• weight fraction
The weight fraction of hexavalent chromium compound can vary but it cannot exceed 40%, and it is dissolved in lab reagents
Substantial (10 - 50%)
• Viscosity low viscosity (like water) low viscosity (like water)
Operating conditions
• Activity class Titration of hexavalent chromium
in the mixture contained in the bath treatment.
Activities with open liquid surfaces or open reservoirs.
Activities with undisturbed surfaces (no aerosol formation).
• Duration 3 min 3 min
• Primary emission source proximity At arm's length. <1m
• Open surface
Laboratory vessel with open surface of approximately 15cm² (0.0015m²) maximum
<0,1m²
Risk management measures
• General ventilation No restriction on general
ventilation characteristics No restriction on general
ventilation characteristics
• General control Measures Titration is performed to a fume
cupboard. Enclosing hood, fume
cupboard.
• Demonstrable and effective housekeeping practices in place
No No
• General housekeeping practices in place
Yes Yes
• Work area Indoors Indoors
• Size of the work area ≈224 m3 (8x7x4m) 300m
3
Version of the modelling tool : ART (Advanced REACh Tool) version 1.5
Table 18: Condition of use of the contributing scenario 3 - modelling
CHEMICAL SAFETY REPORT
44
The ART modelling tool does not take into account all the necessary information for
the risk assessment as required in the CSR. Table 19 presents the necessary
information that does not affect the modelling results.
Parameters Information
Personal protective equipment
• Respiratory protective
equipment Half mask category P3 (EN 143)
• Other personal protective
equipment Protective gloves (chemical gloves approved according to EN 374) and Protective clothes. Technical data sheet in annex.
Other parameters
• Quantity Few millilitres per operation
• Number of workers 1 per operation ; 1 operator involved
• Frequency Weekly period, 12 per week + 8 per month
Exposure value will be validated by working air measure campaign (monitoring). Level of exposure lower than
the estimated level will confirm the risk assessment performed in this CSR.
Table 19: Condition of use for the contributing scenario 3 - other conditions
9.2.3.2. Exposure and risks for workers
The estimated exposure for this contributing scenario is presented in Table 20.
The exposures are presented with and without respiratory protective equipment
(RPE). The description of the RPE used is given at the beginning of section 9.2.
Type of exposure Exposure concentration
estimation Duration of work
Raw exposure, ART estimation -
Without RPE 0.11 µg/m
3 3 min
Raw exposure, ART estimation -
With RPE 0.011 µg/m
3 3 min
Table 20: Exposure estimation - contributing scenario 3
9.2.4. Worker contributing scenario 4: Addition of liquid hexavalent
chromium in bath
This contributing scenario deals with the exposure of workers during the
addition of mixture in the bath treatment, as described in paragraph 9.1.1.1.
9.2.4.1. Conditions of use
In this contributing scenario, exposure is estimated with the modelling approach of
ART (Advanced REACh Tool) version 1.5. The conditions of use described in the Table
21 present the information required for this estimation.
CHEMICAL SAFETY REPORT
45
Parameters Condition of use on the
Nexter’s site Information for modelling
Product characteristics
• Product Mixture containing hexavalent
chromium as supplied in original container
Mixture
• Physical form Chromium trioxide dissolved in a
liquid mixture Powder dissolved in a liquid
matrix
• weight fraction
The weight fraction of hexavalent chromium compound can vary but it cannot exceed 40%. It will be considered as main component, in order to tie in with a precautionary approach.
Main component (50 - 90%)
• Viscosity low viscosity (like water) low viscosity (like water)
Operating conditions
• Activity class Addition of mixture containing
hexavalent compound in the bath treatment.
Transfer of liquid products
Falling liquids, Splash loading
• Flow of transfer
Careful transfer involves workers showing attention to potential danger of splashing, and carrying out the transfer in a very cautious manner.
1-10 l/minute
• Duration
- Addition after drain of tank : 60 min
- Addition to supplement the routine use : 30 min maximum
60 min
• Primary emission source proximity At arm's length. <1m
Risk management measures
• General ventilation Only good natural ventilation Only good natural ventilation
• General control Measures
Transfer of liquid through a small filling opening on the container.
Handling that reduces contact between product and adjacent air.
Local exhaust ventilation fixed on the bath
Fixed capturing hood
• Demonstrable and effective housekeeping practices in place
No No
• General housekeeping practices in place
Yes Yes
• Work area Indoors Indoors
• Size of the work area Approximately 800m3
Large workrooms only (300 to 3000m
3)
Version of the modelling tool : ART (Advanced REACh Tool) version 1.5
Table 21: Condition of use of the contributing scenario 4 - modelling
CHEMICAL SAFETY REPORT
46
The ART modelling tool does not take into account all the necessary information for
the risk assessment as required in the CSR. Table 22 presents the necessary
information that does not affect the modelling results.
Parameters Information
Personal protective equipment
• Respiratory protective
equipment Half mask category P3 (EN 143)
• Other personal
protective equipment Protective gloves (chemical gloves approved according to EN 374) and Protective clothes. Technical data sheet in annex.
Other parameters
• Quantity Variable, performed in order to adjust the concentration of the bath which cannot exceed 40%(w/w) and the total use cannot exceed 0.3 ton per year
• Number of workers 1 / operation ; 4 or 5 operators involved
• Frequency monthly period
Exposure value will be validated by working air measure campaign (monitoring). Level of exposure lower than
the estimated level will confirm the risk assessment performed in this CSR.
Table 22: Condition of use for the contributing scenario 4 - other conditions
9.2.4.2. Exposure and risks for workers
The estimated exposure for this contributing scenario is presented in Table 23.
The exposures are presented with and without respiratory protective equipment
(RPE). The description of the RPE used is given at the beginning of the section 9.2.
Type of exposure Exposure concentration
estimation Duration of work
Raw exposure, ART estimation -
Without RPE 5.4 µg/m
3 60 min or 30 min
Raw exposure, ART estimation -
With RPE 0.54 µg/m
3 60 min or 30 min
Table 23: Exposure estimation - contributing scenario 4
9.2.5. Worker contributing scenario 5: Addition of solid hexavalent
chromium in bath
This contributing scenario deals with the exposure of workers during the
addition of mixture in the bath treatment, as described in paragraph 9.1.1.1.
CHEMICAL SAFETY REPORT
47
9.2.5.1. Conditions of use
In this contributing scenario, exposure is estimated with the modelling approach of
ART (Advanced REACh Tool) version 1.5. The conditions of use described in the Table
24 present the information required for this estimation.
Parameters Condition of use on the
Nexter’s site Information for modelling
Product characteristic
• Product Solid chromium trioxide as
supplied in original container Solid
• Physical form Chromium trioxide Firm granules, flakes or
pellets
• weight fraction Approx. 100% Pure material (100%)
• Moisture content Dry product Dry product (<5 % moisture
content)
Operating condition
• Activity class Addition of hexavalent compound
in the bath treatment.
Transfer of powder, granules or pelletised material
Falling of powders
• Drop height Drop height < 0.5 m Drop height < 0.5 m
• Flow of transfer Cautious manual dumping 1 – 10 kg/minute
• Duration
- Addition after drain of tank : 60 min
- Addition to supplement the routine use : 30 min
60 min
• Primary emission source proximity At arm's length. <1m
Risk management measures
• General ventilation Only good natural ventilation Only good natural ventilation
• General control Measures
The transfer is carrying out the in a very cautious manner.
Careful transfer involves workers showing attention to potential danger.
Local exhaust ventilation fixed on the bath
Fixed capturing hood
• containment of the process Open process Open process
• Demonstrable and effective housekeeping practices in place
No No
• General housekeeping practices in place
Yes Yes
• Work area Indoors Indoors
• Size of the work area Approximately 800m3
Large workrooms only (300 to 3000m
3)
Version of the modelling tool : ART (Advanced REACh Tool) version 1.5
Table 24: Condition of use of the contributing scenario 5 - modelling
CHEMICAL SAFETY REPORT
48
The ART modelling tool does not take into account all the necessary information for
the risk assessment as required in the CSR. Table 25 presents the necessary
information that does not affect the modelling results.
Parameters Information
Personal protective equipment
• Respiratory protective
equipment Half mask category P3 (EN 143)
• Other personal
protective equipment Protective gloves (chemical gloves approved according to EN 374) and Protective clothes. Technical data sheet in annex.
Other parameters
• Quantity Variable, performed in order to adjust the concentration of the bath which cannot exceed 40%(w/w) and the total use cannot exceed 0.5 ton per year
• Number of workers 1 / operation ; 4 or 5 operators involved
• Frequency monthly period
Exposure value will be validated by working air measure campaign (monitoring). Level of exposure lower than
the estimated level will confirm the risk assessment performed in this CSR.
Table 25: Condition of use for the contributing scenario 5 - other conditions
9.2.5.2. Exposure and risks for workers
The estimated exposure for this contributing scenario is presented in the Table
26. The exposures are presented with and without respiratory protective equipment
(RPE). The description of the RPE used is given at the beginning of the section 9.2.
Type of exposure Exposure concentration
estimation Duration of work
Raw exposure, ART estimation -
Without RPE 19 µg/m
3 60 min or 30 min
Raw exposure, ART estimation -
With RPE 1.9 µg/m
3 60 min or 30 min
Table 26: Exposure estimation - contributing scenario 5
CHEMICAL SAFETY REPORT
49
9.2.6. Worker contributing scenario 6: Dipping armament parts in baths
treatment
This contributing scenario deals with the exposure of workers during the dipping
of article in the bath treatment line, as described in paragraph 9.1.1.1.
9.2.6.1. Conditions of use
In this contributing scenario, exposure is estimated with the modelling approach of
ART (Advanced REACh Tool) version 1.5. The conditions of use described in the Table
27 present the information required for this estimation.
Parameters Condition of use on the
Nexter’s site Information for modelling
Product characteristics
• Product mixture of chromium bath Powders dissolved in a liquid matrix
• Physical form Chromium trioxide dissolved in a
liquid mixture Liquid matrix
• Weight fraction
The weight fraction of hexavalent chromium compound can vary but it cannot exceed 40%.
Substantial (10-50%)
• Viscosity Liquids with low viscosity (like
water) Liquids with low viscosity (like water)
Operating conditions
• Activity class Dipping armament parts in
treatment bath.
Activities with open liquid surfaces or open reservoirs.
Activities with undisturbed surfaces (no aerosol formation).
• Duration 40 min 40 min
• Primary emission source proximity
At least at arm's length. <1m
• Open surface ≈0.7 to 1.5m² 1 – 3m²
Risk management measures
• General ventilation Only good natural ventilation Only good natural ventilation
• General control Measures Local exhaust ventilation mounted
on the bath Local exhaust ventilation,
fixed capturing hood.
• Demonstrable and effective housekeeping practices in place
No No
• General housekeeping practices in place
Yes Yes
• Work area Indoors Indoors
• Size of the work area Approximately 800m3
Large workrooms only (300 to 3000m
3)
Version of the modelling tool : ART (Advanced REACh Tool) version 1.5
Table 27: Condition of use of the contributing scenario 6 - modelling
CHEMICAL SAFETY REPORT
50
The ART modelling tool does not take into account all the necessary information for
the risk assessment as required in the CSR. Table 28 presents the necessary
information that does not affect the modelling results.
Parameters Information
Personal protective equipment
• Respiratory protective
equipment (RPE) Half mask category P3 (EN 143)
• Other personal protective
equipment Protective gloves (chemical gloves approved according to EN 374) and Protective clothes. Technical data sheet in annex.
Other parameters
• Quantity The concentration of baths is maintained at a substantial level (10-50%)
• Number of workers Maximum 5 workers
• Frequency every days
Exposure value will be validated by working air measure campaign (monitoring). Level of exposure lower than
the estimated level will confirm the risk assessment performed in this CSR.
Table 28: Condition of use for the contributing scenario 6 - other conditions
9.2.6.2. Exposure and risks for workers
The estimated exposure for this contributing scenario is presented in Table 29.
The exposures are presented with and without respiratory protective equipment
(RPE). The description of the RPE used is given at the beginning of the section 9.2.
Type of exposure Exposure concentration
estimation Duration of work
Raw exposure, ART estimation -
Without RPE 0.86 µg/m
3 40 min
Raw exposure, ART estimation -
With RPE 0.086 µg/m
3 40 min
Table 29: Exposure estimation - contributing scenario 6
CHEMICAL SAFETY REPORT
51
9.2.7. Worker contributing scenario 7: Flushing of the armament part
This contributing scenario deals with the exposure of workers during the
addition of mixture in the bath treatment, as described in paragraph 9.1.1.1.
9.2.7.1. Conditions of use
In this contributing scenario, exposure is estimated with the modelling approach of
ART (Advanced REACh Tool) version 1.5. The conditions of use described in Table 30
presents the information required for this estimation.
Parameters Condition of use on the Nexter’s site Information for
modelling
Primary emission source
Product characteristics
• Product mixture of chromium bath Powders dissolved in a
liquid matrix
• Physical form Chromium trioxide dissolved in a liquid
mixture Liquid matrix
• Weight fraction Water used for rinsing contaminated
surface of the armament part. Very small (0.5-1%)
• Viscosity Liquids with low viscosity (like water) Liquids with low viscosity
(like water)
Operating conditions
• Activity class Flushing of the armament parts above the
treatment bath.
Transfer of liquid products,
Falling liquid
• Type of transfer Rinsing water flows along the armament
part and then falls in the bath. Splash loading
• Flow of liquid product 1 - 10 l/minute 1 - 10 l/minute
• Duration 2 min 2 min
• Primary emission source proximity
At least at arm's length. <1m
Risk management measures
• General ventilation Only good natural ventilation Only good natural
ventilation
• Level of containment of the process
Open process Open process
• General control Measures No localised controls No localised controls
• Demonstrable and effective housekeeping practices in place
No No
• General housekeeping practices in place
Yes Yes
• Work area Indoors Indoors
• Size of the work area Approximately 800m3
Large workrooms only (300 to 3000m
3)
Secondary emission source
Product characteristic
• Product mixture of chromium bath Powders dissolved in a
CHEMICAL SAFETY REPORT
52
Parameters Condition of use on the Nexter’s site Information for
modelling liquid matrix
• Physical form Chromium trioxide dissolved in a liquid
mixture Liquid matrix
• Weight fraction
The weight fraction of hexavalent chromium compound can vary but it cannot exceed 40%.
Substantial (10-50%)
• Viscosity Liquids with low viscosity (like water) Liquids with low viscosity
(like water)
Operating condition
• Activity class Treatment bath located under the
armament part. The rinsing water is falling in the bath.
Activities with open liquid surfaces or open reservoirs.
Activities with agitated surfaces.
• Open surface ≈0.7 to 1.5m² 1 – 3m²
Risk management measures
• General control Measures Local exhaust ventilation mounted on the
bath Local exhaust ventilation,
fixed capturing hood.
• Segregation of the emission source
No segregation No segregation
Version of the modelling tool : ART (Advanced REACh Tool) version 1.5
Table 30: Condition of use of the contributing scenario 7 - modelling
The activity class described for the primary emission source as transfer of liquid with
falling liquid and splashing, permits to takes into account adapted emission
generation mechanism as described in the ART technical report18: gravitation,
impaction and evaporation.
The ART modelling tool does not take into account all the necessary information for
the risk assessment as required in the CSR. Table 31 presents the necessary
information that does not affect the modelling results.
18 Development of a mechanistic model for the Advanced REACH Tool (ART), Version 1.0,
TNO report V9009, page 40
CHEMICAL SAFETY REPORT
53
Parameters Information
Personal protective equipment
• Respiratory protective
equipment (RPE) Half mask category P3 (EN 143)
• Other personal protective
equipment Protective gloves (chemical gloves approved according to EN 374) and Protective clothes. Technical data sheet in annex.
Other parameters
• Quantity Very small (0.5-1%)
• Number of workers Maximum 5 workers
• Frequency every days
Exposure value will be validated by working air measure campaign (monitoring). Level of exposure lower than
the estimated level will confirm the risk assessment performed in this CSR.
Table 31: Condition of use for the contributing scenario 7 - other conditions
9.2.7.2. Exposure and risks for workers
The estimated exposure for this contributing scenario is presented in Table 32.
The exposures are presented with and without respiratory protective equipment
(RPE). The description of the RPE used is given at the beginning of section 9.2.
Type of exposure Exposure concentration
estimation Duration of work
Raw exposure, ART estimation -
Without RPE 20 µg/m
3 2 min
Raw exposure, ART estimation -
With RPE 2.0 µg/m
3 2 min
Table 32: Exposure estimation - contributing scenario 7
9.2.8. Worker contributing scenario 8: Dipping of articles in rinsing baths
This contributing scenario deals with the exposure of workers during the dipping
of article in the bath treatment line, as described in paragraph 9.1.1.1.
9.2.8.1. Conditions of use
In this contributing scenario, exposure is estimated with the modelling approach of
ART (Advanced REACh Tool) version 1.5. The conditions of use described in Table 33
presents the information required for this estimation.
CHEMICAL SAFETY REPORT
54
Parameters Condition of use on the Nexter’s
site Information for modelling
Product characteristics
• Product Mixture of chromium bath Powders dissolved in a liquid matrix
• Physical form Chromium trioxide dissolved in a liquid
mixture Liquid matrix
• Weight fraction Very small (0.5-1%) Very small (0.5-1%)
• Viscosity Liquids with low viscosity (like water) Liquids with low viscosity (like water)
Operating conditions
• Activity class Dipping armament parts in treatment
bath.
Activities with open liquid surfaces or open reservoirs.
Activities with undisturbed surfaces (no aerosol formation).
• Duration 30 min 30 min
• Primary emission source proximity
At least at arm's length. <1m
• Open surface ≈0.7 to 1.5m² 1 – 3m²
Risk management measures
• General ventilation
Only good natural ventilation Only good natural ventilation
• General control Measures
No localised controls No localised controls
• Demonstrable and effective housekeeping practices in place
No No
• General housekeeping practices in place
Yes Yes
• Work area Indoors Indoors
• Size of the work area
Approximately 800m3 Large workrooms only (300 to 3000m
3)
Secondary emission source (far field)
Product characteristics
• Product mixture of chromium bath Powders dissolved in a liquid matrix
• Physical form Chromium trioxide dissolved in a liquid
mixture Liquid matrix
• Weight fraction
The weight fraction of hexavalent chromium compound can vary but it cannot exceed 40%.
Substantial (10-50%)
• Viscosity Liquids with low viscosity (like water) Liquids with low viscosity (like water)
Operating condition
• Activity class Treatment bath located under the
armament part. The rinsing water is falling in the bath.
Activities with open liquid surfaces or open reservoirs.
Activities with undisturbed surfaces (no aerosol formation).
• Open surface ≈0.7 to 1.5m² 1 – 3m²
Risk management measures
CHEMICAL SAFETY REPORT
55
Parameters Condition of use on the Nexter’s
site Information for modelling
• General control Measures
Local exhaust ventilation mounted on the bath
Local exhaust ventilation, fixed capturing hood.
• Segregation of the emission source
No segregation No segregation
Version of the modelling tool : ART (Advanced REACh Tool) version 1.5
Table 33: Condition of use of the contributing scenario 8 - modelling
The ART modelling tool does not take into account all the necessary information for
the risk assessment as required in the CSR. Table 34 presents the necessary
information that does not affect the modelling results.
Parameters Information
Personal protective equipment
• Respiratory protective
equipment (RPE) Half mask category P3 (EN 143)
• Other personal protective
equipment Protective gloves (chemical gloves approved according to EN 374) and Protective clothes. Technical data sheet in annex.
Other parameters
• Quantity Very small (0.5-1%)
• Number of workers Maximum 5 workers
• Frequency every days
Exposure value will be validated by working air measure campaign (monitoring). Level of exposure lower than
the estimated level will confirm the risk assessment performed in this CSR.
Table 34: Condition of use for the contributing scenario 8 - other conditions
9.2.8.2. Exposure and risks for workers
The estimated exposure for this contributing scenario is presented in Table 35.
The exposures are presented with and without respiratory protective equipment
(RPE). The description of the RPE used is given at the beginning of section 9.2.
Type of exposure Exposure concentration
estimation Duration of work
Raw exposure, ART estimation -
Without RPE 0.4 µg/m
3 30 min
Raw exposure, ART estimation -
With RPE 0.04 µg/m
3 30 min
Table 35: Exposure estimation - contributing scenario 8
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9.2.9. Worker contributing scenario 9: Dipping armament parts in baths
treatment, in the worker’s far field
This contributing scenario deals with the exposure of workers during the dipping
of article in the bath treatment line, as described in paragraph 9.1.1.1.
9.2.9.1. Conditions of use
In this contributing scenario, exposure is estimated with the modelling approach of
ART (Advanced REACh Tool) version 1.5. The conditions of use described in Table 36
presents the information required for this estimation.
Parameters Condition of use on the Nexter’s
site Information for modelling
Product characteristics
• Product mixture of chromium bath Powders dissolved in a liquid matrix
• Physical form Chromium trioxide dissolved in a liquid
mixture Liquid matrix
• Weight fraction
The weight fraction of hexavalent chromium compound can vary but it cannot exceed 40%.
Substantial (10-50%)
• Viscosity Liquids with low viscosity (like water) Liquids with low viscosity (like water)
Operating condition
• Activity class Dipping armament parts in treatment
bath.
Activities with open liquid surfaces or open reservoirs.
Activities with undisturbed surfaces (no aerosol formation).
• Duration
Activities are considered as the maximum duration which could be taken into account for one day.
420 min
• Primary emission source proximity
At least at arm's length. <1m
• Open surface ≈0.7 to 1.5m² 1 – 3m²
Risk management measures
• General ventilation Only good natural ventilation Only good natural ventilation
• General control Measures
Local exhaust ventilation mounted on the bath
Local exhaust ventilation, fixed capturing hood.
• Demonstrable and effective housekeeping practices in place
No No
• General housekeeping practices in place
Yes Yes
• Segregation No No
• Personal enclosure No No
• Work area Indoors Indoors
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Parameters Condition of use on the Nexter’s
site Information for modelling
• Size of the work area
Approximately 800m3 Large workrooms only (300 to 3000m
3)
Version of the modelling tool : ART (Advanced REACh Tool) version 1.5
Table 36: Condition of use of the contributing scenario 9 - modelling
The ART modelling tool does not take into account all the necessary information for
the risk assessment as required in the CSR. Table 37 presents the necessary
information that does not affect the modelling results.
Parameters Information
Personal protective equipment
• Respiratory protective
equipment (RPE) Half mask category P3 (EN 143)
• Other personal protective
equipment Protective gloves (chemical gloves approved according to EN 374) and Protective clothes. Technical data sheet in annex.
Other parameters
• Number of workers Maximum 5 workers
• Frequency Every days
Exposure value will be validated by working air measure campaign (monitoring). Level of exposure lower than
the estimated level will confirm the risk assessment performed in this CSR.
Table 37: Condition of use for the contributing scenario 9 - other conditions
9.2.9.2. Exposure and risks for workers
The estimated exposure for this contributing scenario is presented in Table 38.
The exposures are presented with and without respiratory protective equipment
(RPE). The description of the RPE used is given at the beginning of section 9.2.
Type of exposure Exposure concentration
estimation Duration of work
Raw exposure, ART estimation -
Without RPE 0.18 µg/m
3 420 min
Raw exposure, ART estimation -
With RPE 0.018 µg/m
3 420 min
Table 38: Exposure estimation - contributing scenario 9
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9.2.10. Worker contributing scenario 10: Cleaning of the waste collector pit
This contributing scenario deals with the exposure of workers during drain of
bath of the Hafroy Machine, as described in paragraph 9.1.1.1.
9.2.10.1. Conditions of use
In this contributing scenario, exposure is estimated with the modelling approach of
ART (Advanced REACh Tool) version 1.5. The conditions of use described in Table 39
presents the information required for this estimation.
Parameters Condition of use on the
Nexter’s site Information for
modelling
Product characteristics
• Product Drops from chromium bath
diluted in water Powders dissolved in a
liquid
• Physical form Liquid mixture Liquid matrix
• Weight fraction Extremely small (0.1-0.5%) Extremely small (0.1-0.5%)
• Viscosity Liquids with low viscosity (like
water) Liquids with low viscosity
(like water)
Operating conditions
• Activity class Spreading of liquid products Spreading of liquid
products
• Surface concerned Under the duckboard during
120min approximately > 3m² /hour
• Duration 120 min 120 min
• Primary emission source proximity On the ground. >1m
Risk management measures
• General ventilation No restriction on natural
ventilation No restriction on natural
ventilation
• General control Measures No localised controls No localised controls
• Segregation No segregation No segregation
• Personal enclosure No personal enclosure No personal enclosure
• Demonstrable and effective housekeeping practices in place
No No
• General housekeeping practices in place Yes Yes
• Work area Indoors Indoors
• Size of the work area
Small workroom with air exchange with the plating shop through the duckboard
Small workrooms only
Version of the modelling tool : ART (Advanced REACh Tool) version 1.5
Table 39: Condition of use of the contributing scenario 10
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The ART modelling tool does not take into account all the necessary information for
the risk assessment as required in the CSR. Table 40 presents the necessary
information that does not affect the modelling results.
Parameters Information
Personal protective equipment
• Respiratory protective
equipment (RPE) Half mask category P3 (EN 143)
• Other personal protective
equipment Protective gloves (chemical gloves approved according to EN 374) and Protective clothes. Technical data sheet in annex.
Other parameters
• Quantity Extremely small (representing 0.1-0.5% of the water spread)
• Number of workers 1 worker per operation
• Frequency Twice a year
Exposure value will be validated by working air measure campaign (monitoring). Level of exposure lower than
the estimated level will confirm the risk assessment performed in this CSR.
Table 40: Condition of use for the contributing scenario 10 - other conditions
9.2.10.2. Exposure and risks for workers
The estimated exposure for this contributing scenario is presented in Table 41.
The exposures are presented with and without respiratory protective equipment
(RPE). The description of the RPE used is given at the beginning of section 9.2.
Type of exposure Exposure concentration
estimation Duration of work
Raw exposure, ART estimation -
Without RPE 23 µg/m
3 120 min
Raw exposure, ART estimation -
Without RPE 2.3 µg/m
3 120 min
Table 41: Exposure estimation - contributing scenario 10
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10. RISK CHARACTERISATIO N RELATED TO
COMBINED EXPOSURE
10.1. Human health (related to combined exposure)
This CSR analyses only hexavalent chromium exposure at the workplace for an
industrial use. There is no possibility of exposure for professional use. The risk
characterization is performed for the site of Tulle concerned by the Use-1, 2 & 3.
10.1.1. Workers distribution of tasks
Two populations of exposed workers are concerned by the use of hexavalent
chromium in this CSR:
- five main workers involved in the operations performed for the chromium
treatment and
- one laboratory worker involved only for the sampling and lab analysis.
Within the main worker population, activities are spread evenly. The detail of the
durations of activities for these workers is given in Table 42 and Table 43.
Time/frequency CS-2
Sampling
CS-3
Titration
Duration of the task 2 min 3 min
Frequency
(for 1 laboratory worker)
1 /week/bath
44 x 4 / year
12/week + 8/month
(44x12 + 12x8) / year
Table 42: timeline of chromium activities for the laboratory worker
Time/frequency
CS-4 (for Use-3)
Addition - liquid
CS-5 (for Use-1&2)
Addition - Solid CS-6
Dipping -
Baths
treatment
CS-7
Flushing
CS-8
Dipping -
Rinsing
baths
CS-9
Dipping -
Far field
CS-10
Cleaning
pit After drain Routine
supplement After drain
Routine
supplement
Duration of the task
60min 30min 60 min 30 min 40 min 2 min 30 min 420 min 120 min
Frequency
(for 5 workers of the plating shop)
1 / 4 year
1 / month
for the black chromium bath
(12 / year)
3 / 4 years
1 / month
/ bath (3 hard chromium
baths)
(12 x 3 / year)
5 x 5 / week
44 week / year
5 x 5 / week
44 week / year
5 x 5 / week
44 week / year
5 x 5 / week
44 week / year
2 / year
Frequency
(for 1 of the 5 workers of the plating shop)
(0.25/5) / year
(12/5) / year (0.75/5) /
year (12x3/5) /
year (5 x 44) /
year (5 x 44) /
year (5 x 44) /
year (5 x 44) /
year 0,4 / year
Table 43: timeline of chromium activities for main workers
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In order to assess an exposure specific for each use, the frequencies are split for each
use.
Regarding the contributing scenario 2, 3, 4 and 5 these activities are related to the
number of baths concerned. Hence, for these activities the split of frequencies will
be as follow:
- Use-1&2: 3 of the 4 baths of the plating shop, which means that the
frequencies will be adjusted to ¾. Then the remaining frequencies will be
spread evenly between both uses (50% for Use-1 and 50% for Use-2). The
frequencies will be thus adjusted by 3/8 for the Use-1 and equally for the
Use-2.
- Use-3: 1 of the 4 baths of the plating shop which means that the frequencies
will be divided by 4.
Regarding the rest of the activities, the split of frequencies will be performed
regarding the tonnage of substance used for the Use 1&2 on the one hand and for
the use 3 on the other hand. Then, the quantities between Use 1 and 2 will be spread
evenly between both uses (50% for Use-1 and 50% for Use-2). The frequencies will
therefore be considered as follow:
- Use-1&2: 62.5% (corresponding to 500kg/800kg)
o Use 1: 31.25%
o Use 2: 31.25%
- Use-3: 37.5% (corresponding to 300kg/800kg).
Consequently, the time and frequencies can be presented as follow:
For the Use 1:
Time/frequency CS-2
Sampling
CS-3
Titration
Duration of the task 1 min 3 min
Frequency
(for 1 laboratory worker)
(44 x 4 x 3/8) / year
((44 x 12 + 12 x 8) x 3/8) / year
Table 44: timeline of chromium activities for the laboratory worker for use-1
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Time/frequency
CS-4 (for Use-3)
Addition - liquid
CS-5 (for Use-1&2)
Addition - Solid CS-6
Dipping -
Baths
treatment
CS-7
Flushing
CS-8
Dipping -
Rinsing
baths
CS-9
Dipping -
Far field
CS-10
Cleaning
pit After drain Routine
supplement After drain
Routine
supplement
Duration of the task
60min 30 min 60 min 30 min 40 min 2 min 30 min 420 min 120 min
Frequency
(for 1 of the 5 workers of the plating shop)
Not concerned
Not concerned 0.075 / year 3.6 / year 68.75/year 68.75 /year
68.75/year 20.625/year 0,125 / year
Table 45: timeline of chromium activities for main workers for use-1
For the Use-2:
The Tables 45 and 46 are the same as the information considered for the Use-2.
For the Use-3:
Time/frequency CS-2
Sampling
CS-3
Titration
Duration of the task 1 min 3 min
Frequency
(for 1 laboratory worker) (44 x 1 / year) (44 x 1 / year)
Table 46: timeline of chromium activities for the laboratory worker for use-1
Time/frequency
CS-4
Addition - liquid
CS-5
Addition - Solid CS-6
Dipping -
Baths
treatment
CS-7
Flushing
CS-8
Dipping -
Rinsing
baths
CS-9
Dipping -
Far field
CS-10
Cleaning
pit After drain Routine
supplement After drain
Routine
supplement
Duration of the task
60min 30min 60 min 30 min 40 min 2 min 30 min 420 min 120 min
Frequency
(for 1 of the 5 workers of the plating shop)
0.05 / year 2.4 / year Not
concerned Not
concerned 82.5/year
82.5
/year 82.5/year 82.5/year 0.15 / year
Table 47: timeline of chromium activities for main workers for use-1
10.1.2. Exposures estimations for the populations of workers
The exposures for the two populations of workers (main workers and laboratory
worker) are presented in the following tables.
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On the basis of duration and frequency of each Contributing Scenario, the average
exposure on one year is calculated as follows:
∑
The exposure of each Contributing Scenario involved in the activity considered will
be used in this calculation. The total duration of work over one year is considered for
480min/day, 5day/week and 44week/year.
For the Use 1:
Laboratory worker CS-2
Sampling CS-3
Titration
Duration 2 min 3 min
Raw exposure (in µg/m3 ; with RPE)
0,087 0,011
Frequency (for 1 laboratory worker)
(44 x 4 x 3/8) / year ((44 x 12 + 12 x 8) x 3/8) / year
Average exposure on one year adjusted by durations and frequencies
(in µg/m3 ; with RPE) 0.00018
Table 48: Exposure for laboratory worker for the Use-1
Main worker
CS-4 CS-5 CS-6 CS-7 CS-8 CS-9 CS-10
Addition - liquid Addition - Solid Dipping -
Baths treatment
Flushing Dipping - Rinsing baths
Dipping - Far field
Cleaning pit
After drain
Routine supplement
After drain
Routine supplement
Duration 60min 30min 60 min 30 min 40 min 2 min 30 min 420 min 120 min
Raw exposure 0,54 1,9 0,086 2 0,04 0,018 2,3 (in µg/m3 ;
with RPE)
Frequency
Not concerned
Not concerned
0.075 / year
3.6 / year 68.75 /year
68.75 /year
68.75 /year
68.75 /year
0,125 /year
(for 1 of the 5 workers of the plating shop)
Average exposure on one year adjusted by durations and frequencies
0,013
(in µg/m3 ; with RPE)
Table 49: exposure for main workers for the Use-1
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For the Use-2:
Tables 48 and 49 are the same as the information considered for the Use-2.
For the Use-3:
Laboratory worker CS-2
Sampling CS-3
Titration
Duration 2 min 3 min
Raw exposure (in µg/m3 ; with RPE)
0,087 0,011
Frequency (for 1 laboratory worker)
(44 x 1 / year) (44 x 1 / year)
Average exposure on one year adjusted by durations and frequencies
(in µg/m3 ; with RPE)
0.00012
Table 50: Exposure for laboratory worker for the Use-3
Main worker
CS-4 CS-5 CS-6 CS-7 CS-8 CS-9 CS-10
Addition - liquid Addition - Solid Dipping -
Baths treatment
Flushing Dipping - Rinsing baths
Dipping - Far field
Cleaning pit
After drain
Routine supplement
After drain
Routine supplement
Duration 60min 30min 60 min 30 min 40 min 2 min 30 min 420 min 120 min
Raw exposure 0,54 1,9 0,086 2 0,04 0,018 2,3 (in µg/m3 ;
with RPE)
Frequency
0.05 / year
2.4 / year Not
concerned Not
concerned 82.5 /year
82.5 /year
82.5 /year
82.5 /year
0,15 / year
(for 1 of the 5 workers of the plating shop)
Average exposure on one year adjusted by durations and frequencies
0,013
(in µg/m3 ; with RPE)
Table 51: Exposure for main workers for the Use-3
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10.1.3. Comparison between modelling and monitoring
During the last campaign measurement (2015), the ambient concentration in the
plating shop was measured in five different places in the room. These measurements
were performed under quality control according to COFRAC accreditation.
These measurements are compared to modelling estimations in the following table.
All the exposures are presented without RPE.
2015 campaign
Ambient measurement
CS-9 Dipping - Far field
Modelled exposure (in µg/m3 ; without RPE) 0.18
measured exposure N°1 (µg/m3 ; without RPE) 0.11
measured exposure N°2 (µg/m3 ; without RPE) 0.12
measured exposure N°3 (µg/m3 ; without RPE) 0.09
measured exposure N°4 (µg/m3 ; without RPE) 0.25
measured exposure N°5 (µg/m3 ; without RPE) 0.09
Average measured exposure (in µg/m3 ; without RPE) 0.13
Table 52: 2015 campaign - ambient measurement
Measurements taken before 2015 were not performed with a methodology designed
for the measurement of ambient concentration in the range of µg/m3. Consequently,
they were deemed not relevant (because of high quantification limits) and were not
used in this CSR.
Considering the data presented in Table 52, modelling estimations will be considered
as the representative level of exposures at the workplace. These estimations will be
used for the calculations of excess risk.
10.1.4. Risk characterisation
As discussed previously in chapter 9.1.2.3, the risk characterisation will be based on
the RAC/27/2013/06 Rev.1 which establishes a reference dose response
relationship for the carcinogenicity of hexavalent chromium.
Excess of lung cancer risk: 4*10-3 per μg Cr(VI)/m3 based on a 40 years working life
(8h/day, 220 days per year)
Moreover, and since chromium exposures are due to the volatility of a liquid
mixture, we estimated the cancer risk mainly for lung cancer and maximised the
excess of cancer risk without considering the risk for small intestine cancer.
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Based on all of this information, the tables below show the calculation of the excess
risk for lung cancer weighted by the working conditions on the NMe site of Tulle.
Weighted excess risk of lung cancer Value
Excess risk of lung cancer. per µg/m3 of Cr(VI)
based on 40 working years. 220 days per year.
8h per day (RAC 2013) 4x10-3
Excess risk of lung cancer. per µg/m3 of Cr(VI)
based on 1 working years. 220 days per year.
8h per day 1x10-4
Excess risk of lung cancer. per µg/m3 of Cr(VI)
based on 7 working years. 220 days per year.
8h per day 7x10-4
Excess risk of lung cancer. per µg/m3 of Cr(VI)
based on 12 working years. 220 days per year.
8h per day 1.20x10-3
Table 53: Excess risk of lung cancer calculation
Considering the data presented in table 54 and the exposure estimations based on
the modelling approach, the excess risk are calculated for each use in the following
tables.
For the Use-1:
Parameter for a main worker Value
Individual excess risk calculation for one main
worker for the requested review period
(12years) for the Use-1 1.55x10-5
Total excess risk calculation for the five main
workers for the requested review period (12
years) for the Use-1 7.74x10-5
Table 54: Excess of lung cancer risk calculation for one main worker for Use-1
Parameter for a laboratory worker Value
Individual excess risk calculation for the only
one laboratory worker for the requested
review (7 years) period for the Use-1 2.18x10-7
Table 55: Excess of lung cancer risk calculation for the only one laboratory worker for Use-1
CHEMICAL SAFETY REPORT
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For the Use-2:
Parameter for a main worker Value
Individual excess risk calculation for one main
worker for the requested review period (7
years) for the Use-2 9.03x10-6
Total excess risk calculation for the five main
workers for the asked review period (7 years)
for the Use-2 4.51x10-5
Table 56: Excess of lung cancer risk calculation for one main worker for Use-2
Parameter for a laboratory worker Value
Individual excess risk calculation for the only
one laboratory worker for the requested
review (7 years) period for the Use-2 1.27x10-7
Table 57: Excess of lung cancer risk calculation for the only one laboratory worker for Use-2
For the Use-3:
Parameter for a main worker Value
Individual excess risk calculation for one main
worker for the requested review period (7
years) for the Use-3 9.40x10-6
Total excess risk calculation for the five main
workers for the requested review period (7
years) for the Use-3 4.70x10-5
Table 58: Excess of lung cancer risk calculation for one main worker for Use-3
Parameter for a laboratory worker Value
Individual excess risk calculation for the only
one laboratory worker for the requested
review (7 years) period for the Use-3 8.49x10-8
Table 59: Excess of lung cancer risk calculation for the only one laboratory worker for Use-3
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The following table summarise all the total excess risk considered in the Uses-1, 2&3
of this CSR.
Population Use-1 Use-2 Use-3 Total per
Pop°
Main worker (Use-1,2,3 -
Tulle)
Nb. worker 5 5
Total excess risk
7.74 x10-5 4.51 x10-5
4.70 x10-5 1.70 x10-4
Laboratory worker
Nb. worker 1
Total excess risk
2.18 x10-7 1.27 x10-7
8.49 x10-8 4.30 x10-7
Total per Use 7.76 x10-5 4,53 x10-5
4,71 x10-5 1.70 x10-4
Table 60: summary of all the excess risk for Use1,2&3
The decision point for 'acceptable' lifetime (i.e., a working life of 40 years) cancer risk
levels used for individual risks levels workers are generally around 10-5 but higher or
lower levels have been considered to be tolerable under certain circumstances19.
The total excess of risk for all the workers involved in the operations using
hexavalent chromium for the Use-1,2&3 on the site of Tulle are respectively:
7.76x10-5 ; 4.53x10-5 & 4.71x10-5
10.1.5. Combined exposure with the Use-4
Combined exposure exist for the laboratory worker involved in the sampling and
titration described for the Uses1,2&3 and the same operations for the Use-4 on the
site of Tulle described in a separate CSR.
The total excess risk for all the uses (1,2,3&4) for the laboratory worker is calculated
at
5.60x10-7
The following table described all the total excess risk for all the workers involved in
the 4 uses described in the Nexter AfA.
19 Guidance on information requirements and chemical safety assessment Chapter R.8:
Characterisation of dose concentration-response for human health
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Population Use-1 Use-2 Use-3 Use-4 Total per
Pop°
Main worker (Use-1,2,3 -
Tulle)
Nb. worker 5 - 5
Total excess risk
7.74x10-5
4.51x10-5
4.70x10-5
- 1.70x10-4
Laboratory worker
Nb. worker 1 1
Total excess risk
2.18x10-7
1.27x10-7
8.49x10-8
1.30x10-7
5.60x10-7
Main worker (Use-4 - Tulle)
Nb. worker - - - 2 2
Total excess risk
- - - 9,40x10-6
9,40x10-6
Main worker (Roanne)
Nb. worker - - - 2 2
Total excess risk
- - - 1.33x10-5
1.33x10-5
Substitute worker
(Roanne)
Nb. worker - - - 2 2
Total excess risk
- - - 2.17x10-6
2.17x10-6
Total per Use 7.76x10-5
4,53x10-5
4.71x10-5
2.50x10-5
1.95x10-4
Table 61: Summary of all the excess risk for the Nexter AfA
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10.1.6. Analysis of uncertainties and improvement of management
The exposures considered in this CSR for the Use-1,2&3 are based on several
hypotheses. They were made in order to respect a conservative approach and
consequently, led to an overestimation of the exposure. They mainly concern the
following items:
1. Definition of the APF:
The applicant made the choice to tie in with a precautionary approach by
using an APF of 10 for the RPE used. This APF used would have been higher
but the applicant made the choice to present an assessment with no
potential doubt on the RPE used.
2. Modelling approach
All measurements performed on Nexter’s site and presented in this CSR
show lower values than the modelling estimations. Consequently, modelling
estimations are considered as the maximum level of exposures at the
workplace. Even if the modelling approach is demonstrated to be an over
estimation, the applicant made the choice to use this approach in order to be
sure that the assessment is covering all the tasks involved in the use of
hexavalent chromium.
3. Inputs for modelling
The inputs used for modelling cannot be strictly representative of the
realistic use performed on site. In order to be completely transparent, for all
the contributing scenarios, the inputs used are compared to the condition of
use on the Nexters’ sites in a three columns table (for example the tables 16
or 19). All the inputs have been chosen in order not to under estimate the
exposure estimation for each contributing scenario.
4. Duration of tasks and frequency used
The duration and the frequencies of the tasks were considered by taking into
account the maximum possible increase of activity presented in accordance
with the tonnage estimation. It does not probably reflect the exact
frequencies and duration involved during the review period, but the
applicant made the choice to present the maximum realistic estimation in
order to cover potential future activities.
Hence, the excess risk previously presented can be considered as the maximum
consideration, taking into account all uncertainties.
Furthermore, the compliance with the operating conditions described in this
CSR will be periodically controlled and the efficiency of the risk management
measures (mainly ventilations and RPE) will be regularly verified according to a
written procedure. All workers involved will be made aware of the best practices of
work to ensure that the level of exposure is as low as possible.
By now, the applicant will furthermore perform measurements adapted to the
contributing scenarios in order to confirm that the measured level of exposure will
CHEMICAL SAFETY REPORT
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be lower than the levels estimated in this CSR by modelling approach. Consequently,
measurement of atmospheric emission will be performed each year, and
measurement at the workplace will be performed in order to verify the main raw
exposures estimated with the modelling approach.
The applicant therefore took the opportunity of this CSR to critically assess
RMMs and OCs in place. In spite of the encouraging results obtained, Nexter will
engage in the improvements described above so as to continuously reduce the risk
over the review period.