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Textile Cleanroom Garments

The only filter between wearer and product

Represented in Europe in several countries with distributors and production lines

“Headquarter” in Muggensturmincl. QA, production management, R & D etc.own sales force in BeNeLux and UK

1 production line in Hungary:With approx. 1.000 – 2.000 bigger pcs. per week

New distributors in Rumania and Bulgaria

2 production lines in Portugal:1 x with approx. 1.600 bigger pcs per week

1 x with approx. 500 –1.000 pcs undergarment per week

Distributors in:Sweden, Denmark, UK, CZ, Switzerland, Hungary and Slovenia, Portugal

Dastex Reinraumzubehör GmbH & Co. KG

Partner in a European Cleanroom Network

Dastex Reinraumzubehör GmbH & Co. KG - www.dastex.com

� leading European producer for textile cleanroom garments

� several production facilities in Europe (design, planning, quality and end control in Germany

� production capacity per week on average:2.500 – 3.000 large pieces (if needed 4.000 pcs)

� Dastex has in addition to textile garments and undergarments all typical clean room products in its range, such as:

� gloves, wipers, tacky mats, paper, products for cleaning and disinfectants, shoes, mobile units, technical equipment, furniture, etc.

� also in this segment Dastex belongs to the market leader

Dastex Reinraumzubehör GmbH & Co. KG


Dastex Cleanroom Garments

customized concepts


More than 30 years experiences !


1. Introduction

2. Characteristics of a cleanroom textile

3. System of outer and undergarments

4. Summary

Textile Cleanroom Garments


20 ... 30 % 30 ... 40 %

5 ... 10 %20 ... 30 %

10 ...20 %

Persons

Process Mediums like GasesMachines / Equipment

Air / Filtration

running operation

Sources of particles in the cleanroom

Introduction

Textile Cleanroom GarmentIntroduction

The main task of cleanroom garments is to

protect the product / process from contamination

by human beings and his personal garments.

Introduction

Sourface: Street Wear Sourface: Street Wear

Sourface:Cleanroomtextile



Characteristics of a cleanroom textile

• Particle retention capacity against air-borne particles

• Migration behaviour

• Abrasion resistance/Napping tendency

• Electrostatic behaviour

• Wearing comfort (skin sensorical and thermophysically attributes)

• Decontamination

• Sterilisation

• AMC – cleanroom garment


Particle retention capacity against airborne particles


Filtration tests on a cleanroom textile might be

influenced among others by:

a) Kind and size of the test particles

b) Kind, flow speed and temperature of the gas

c) Size and side of the textile tested

d) Duration of the test




• In order to compare different cleanroom textilesit is indispensible that the tests are made underthe same conditions (neutral).

• To simulate aging processes it is recommended,that the fabric samples are washed undercleanroom conditions at least 50 times.

• To control that the data is constant over years,the tests have to be repeated in selectedintervals.



Example the Cleanroom-fabric A

Producer information: 90 % (0,1 - 0,3 µm)

Test results of BTTG (UK):Particle size (µm) 0,19 - 0,3 0,3 - 0,5 0,5 - 1,0 1,0 - 3,0 3,0 - 5,0CR-fabric A 64,9 % 87,2 % 94,9 % 94,8 % 95,0 %

Test results of ITV-Denkendorf (Time: 60 minutes), CR-fabric A :A) Particle concentration of 10 mg/m³ Particle size 0,5 µm: 75 %

5,0 µm: 92 %B) Particle concentration of 100 mg/m³ Particle size 0,5 µm: 98 %

5,0 µm: 99,9 %C) The new Test Stand

Crude gas concentration: 25 mg/m³ 0,5 µm: 92 %Flow speed: 5 cm/s 1,0 µm: 94 %Average particle size: 2,0 µm 5,0 µm: 97 %


Migration behaviour

Between garment and undergarment there are areas without space and air

Particles and fibers will migrate mechanically at those places through the textile

source: ITV - Denkendorf

Textile has the function of „buffer“


Abrasion resistance / Napping tendency

• Synthetic fibers like e.g. polyester or polyamide/nylon considerably meet these requirements better thannatural fibers such as cotton or mixed fibers like e.g.a cotton-polyester textile (35%/65%)

• These are characteristics for the condition of use and for the material ageing caused by decontamination.



Quelle: ITV Denkendorf


2 mm


3/2-twill-constructiontested by Martindale with

4.000 revs

1/1 plain-constructiontested by Martindale with

4.000 revs

Alternative for Martindale tests:Rubbing Cleanroom fabrics � Cleanroom fabrics


Electrostatic behaviour

Polyamidefiber Polyesterfiber Polyesterfiber

Copper centre (T-25)Carbon membrane Carbon diagonal

Distance betweenthe centre and the

edge of the fiber

is rather big.

Further a copper centre is not suitable for allapplications.

Effect of carbonabrasion

Structureof the fiber

Formation of thecarbon fibers

Electrostaticbehaviour

There is a good

continuity at the

edge and internal

support from the

polyester fibre.

If a carbon fiber

is interrupted the

charge is diverted

along another

path due to the

grid system



Intact antistatic

fiber

First damages on

the antistatic fiber

Destroyed antistatic

fiber

Source: ITV - Denkendorf



Polyamidefiber Polyesterfiber Polyesterfiber

Copper centre (T-25)Carbon membrane Carbon diagonal

Distance betweenthe centre and the

edge of the fiber

is rather big.

Further a copper centre is not suitable for allapplications.

Effect of carbonabrasion

Structureof the fiber

Formation of thecarbon fibers

Electrostaticbehaviour

There is a good

continuity at the

edge and internal

support from the

polyester fibre.

If a carbon fiber

is interrupted the

charge is diverted

along another

path due to the

grid system


Wearing comfort

Skin sensorical attributes are:

a) Adhesive tendency (of the textile on sweaty skin)b) Scratching due to roughness of the textilec) Local pressure caused by bending strength of the

textile ( ==> „Grip“ or „ Softness“)

(The subjective feeling of the respective wearer playsan important role here)


Wearing comfort

• Thermo physically attributes are:

a) Heat transport behavior

b) Water vapor diffusion resistance

• Most of the test methods concentrate on

thermo physically factors.


Wearing Comfort

Source: Hohensteiner Institute

Skin-Simulation-Model

25

Wearing Comfort

source: Hohensteiner Institute

Hautsimulationsmodell



Wearing Comfort /CERTIFICATION

Measurements for:- ION-NOSTAT-VI.2,- ION-NOSTAT-Plus and- ION-NOSTAT-Comfort are based on tests with the „thermoregulationmodel“ of the human skin.

Test standards:DIN EN 31092 (02/94) resp. ISO 11092 (10/93)


Decontamination

• Textile cleanroom garments have the function of a „buffer“ (cf. 2.2.) which has to be „discharged“ within fixed periods.Additionally there are particles on the surface (possibly from the work process) that need to be removed and of course hygienic reasons.

• There are two test methods to determine rest decontamination (after the “washing” process):a) ASTM F 51-00b) Helmke Drum Test

Decontamination

source: RCPE (Graz)



Decontamination

Schedule for a „typical cleanroom laundry“

Rest contamination at conventional washing procedure:The textile is a filter for the remaining particles in the liquid


Sterilisation

Only for users who work/produce/fill/pack

under sterile conditions.

Mainly used procedures:

Autoclaving (121°C/134°C)

Gamma-Irradiation (25kGy)


Sterilisation

• Both methods have special requirements to the cleanroom garments (especially to components like zippers, buckles, press buttons etc.).

• Both methods are not considered to save the material. After 50-60 sterilisation at the latest (according to the above methods) the garments needs to be replaced.

AMC

• until today there are no studies published

regarding AMC and cleanroom fabrics and/or

cleanroom garments.

• AMCs can be caused by treatments which are

used during the weaving process � for

example that fibers do not stick together.

Before the first use cleanroom garments have to

be decontaminated!

• Until today there is no definitive filtration

efficiency for cleanroom garments of AMCs.



Cleanroom garments and undergarments as a system

• There are 3 mechanisms how people contaminate their surrounding area despite of wearing cleanroom garments:

- thermal jet inside the garment (caused by body heat)

- building of excess pressure inside the cleanroomgarment by movement (= pump effect)

- emission through the cleanroom textile



Besides of diffusion/emission contaminated air escapes inevitable through the following necessary garment openings:

- arm and leg openings- neckline/face openings and overlaps e.g. hood/coveralls)- fasteners (zippers, button facing, velcro)- seams


Cleanroom garments

and undergarments as a system

Qualitative representation of the local particle emissionof a person wearing conventional cleanroom garments

Product

Table/ bench

2

5

7

3

2

1

4

6

5

8

Source: VDI-Verlag, Reihe 3, Verfahrenstechnik, Nr. 447Hottner: Optimierung von Reinraumkleidung

1 Breath filtered by theface mask

5 Area jet filtered by thetextile

6 Emission through the zipper(without cover)

7 Emission through the seam

2 Thermal jet(neckline/collar)

3 Thermal jet increased bypump effect (movement)

4 When breathing out there isa diversion of the thermal jetfrom the collar area

8 Emission through arm border(only if there is pump effect)

Vertical driving air (0,45 m/sec.)



• An interesting conclusion from Hottner's investigations is to demand a minimum air permeability for cleanroom textiles:

> 10 l/(dm² * min), at � P = 200 Pa and

< 30 l/(dm² * min), at � P = 200 Pa

• This seems to be in contrary to the meaning that a cleanroom fabric must be as close as possible



Balanced Air permeability

� The overpressure inside the garment system can be

reduced at the whole area in a constant way.

� The „pump effect“ will be reduced. The risk of

contamination of the product, caused by bundled uncontrolled out breaking airstreams (hands and/or head/neck area) will be minimized.


Cleanroom garments and undergarments as a systemExaminations dealing with the subject of the „pump effect“



• 3 Cleanroom fabrics have been compared (Class ISO-5 and better).

• The technical data for the more air permeable fabric (C) was about 29 l/min x dm² (at 200 Pa), the other tested fabrics were at about 4,9 l/min x dm² (A) and resp. 10,7 l/min x dm² (B) (at 200 Pa).

• From those materials coveralls, full cover hoods and over boots (knee-level) have been produced all in identical design (cut). The test persons wore a two-piece jogging suit made from 100% cotton (also identical cut).

• Standardized face cover system.

• At Pre-Tests pressure differences from 30 Pascal and more have been measured.



• The Cleanroom at ITV-Denkendorf is comparable to Cleanroom class ISO-4 / ISO-5 (at vertical air flow of 0,45m/sec, at 21 bis 22 °C and approx. 45 % relative air humidity)

• Test persons should do some easy movements for 15 minutes for acclimatization.

• Before starting the movement program 4 measurements have been executed (each 15 sec.) without any movements.

• After 4 „Silent measurements“ 8 Measuring's (again each 15 sec.) were taken while moving (simulation of walking).

• After every movement loop a minimum of 8 measurements „in normal position“ were taken (which means without any movements – if necessary the „neutral phase“ must be extended).

• 10 repetitions per test person each with 2 complete test sets.


Particle generation Person 1 w ith 2. Sets per 2 min. w alking - Particle size 0,5 µm

0

5000

10000

15000

20000

25000

30000

1 2 3 4 5 6 7 8 9 10

Measurements

Qua

ntity

of

prat

icle

s si

ze 0

,5 µ

m

A (2. Set)

B (2. Set)

C (2. Set)



Particle generation Person 1 w ith 2. Sets per 2 min. "normal phase" w /o mov ements -

Particle size 0,5 µm

0

5000

10000

15000

20000

1 2 3 4 5 6 7 8 9 10

Messungen

Qua

ntity

of

part

icle

s si

ze 0

,5

µm

A (2. Set)

B (2. Set)

C (2. Set)



Cleanroom garments and

undergarments as a system

Many times people pay no or only little

attention to undergarments although one

bigger share of contamination will be

generated by this source of pollution.



The main tasks for cleanroom suitable

undergarments are:

• not being a source of particles and emission

• being a barrier for particles caused by skin and

underwear

• being a „buffer“ for such particles

• increase of the wearing comfort

– Heat isolation

– Humidity storage


Cleanroom garments and

undergarments as a system

With the help of a defined undergarment it is

easily possible to reduce particles and germs in

the cleanroom garments system.

At least: 50% !



0

50

100

150

200

250

cfu

pe

r 1

00

cm

²

Pers. A Pers. B Pers. A Pers. B Pers. A Pers. B

Influence of the undergarment of the mikrobiological

contamination of cleanroom garments

Cotton

Light Tech

directly after having having made simulation of

dressed the 1. time several exercises repeated wears

1. Garment set



0

10

20

30

40

50

60

70

80

90

100

cfu

pe

r 1

00

cm

²

Pers. A Pers. B Pers. A Pers. B Pers. A Pers. B

Influence of the undergarment of the mikrobiological

contamination of cleanroom garments

Cotton

Light Tech

directly after having having made simulation of

dressed the 1. time several exercises repeated wears

2. Garment set



0

5000

10000

15000

20000

25000

30000

35000

40000

45000

50000

> 0,3 µm > 0,5 µm > 1 µm

Cotton, 1. Set, Neck-Level

Light Tech, 1. Set,Neck-Level

Cotton, 1. Set,Working-Level

Light Tech, 1. Set,Working-Level

Influence of the undergarment of the contamination of the cleanroom

air: Person 1, 1. Garment set



0

5000

10000

15000

20000

25000

30000

> 0,3 µm > 0,5 µm > 1 µm

Cotton, 1. Set, Neck-Level

Light Tech, 1. Set,Neck-Level

Cotton, 1. Set,Working-Level

Light Tech, 1. Set,Working-Level

Influence of the undergarment of the contamination of the cleanroom

air: Person 2, 1. Garment set


Summary

• There is a careful selection required of the „only filter"between humans as source of contamination and the product.

• Reliable, verifiable, textile specific data's should form the basis of decisions, like:- particle retention- air permeability- electrostatic behavior- water vapor diffusion resistance- etc.


Summary

• Furthermore there are manufacturing features like:- seams- fit- etc.

• Cleanroom garments must be seen as a system that is influenced by:- excess pressure- thermal jets

• Cleanroom undergarments are an important component of the cleanroom garment system and are sometimes still underestimated.


Summary

• Of course also a professional decontamination belongs to a cleanroom garment system.

• It is unavoidable that the staff will need to have trainingsregarding this topic because it is pretty comprehensiblethat this system can only work as desired if theemployees (= wearer of the cleanroom garments) aretrained and motivated accordingly.


Thank you very much

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