seguridadina rf vs03

7/29/2019 SeguridadINA RF Vs03

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Basic Safety & Security Course - INA

PhysicalPhysical HazardsHazards


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LaserLaser RadiationRadiation HazardsHazards

Jean Michel Jarre laser harp

Laser: Red (635nm), Green (532nm), Blue (445nm)

Air Force Research Laboratory multipleinteracting laser rays.

PhysicalPhysical CharacteristicsCharacteristics


The name "LASER" is an acronym for"LightAmplification byStimulatedEmission ofRadiation".

. Ordinary light that comes from a conventional light source

radiates in all directions andin various wavelengthsthat reinforce or cancel each other.

. Light from a laser beamDirectional (travels in one direction)Monochromatic (a specific wavelength only)Coherent (in phase)

Two coherent waves


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Laser radiation may be released as

continuous wavelaser beam

pulsedlaser beam

Q-switchedlaser beam

Thinner pulses give higher peaks for same average Power.

Lasers can be more hazardous than ordinary light becausethey can focus a lot of energy onto a small area.



Laser beams are not limited to visible wavelengths only. Laserunits can be designed over a wide range of frequencies, frominfrared to ultraviolet regions.

Optical portion of Electromagnetic Spectrum

Near-IR (IR-A) (780 nm 1400 nm)

Far-IR (IR-B, IR-C) (1400 nm 1 mm)

Near-UV (UV-A) (315 nm 400 nm)Far-UV (UV-B, UV-C) (200 nm 315 nm)


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DemageDemage MechanismsMechanisms


Lasers can cause damage in biological tissues due to its great brightness ofbeam, both to the eye and to the skin, due to different mechanisms:

- Thermal damage (burn): tissues are heated to the point wheredenaturation of proteins occurs.

- Photochemical damage: light triggers chemical reactions in tissue.Mostly with blue and ultra-violet light and can be accumulated over thecourse of hours.

. The eye is, by far, the organ of the body most

subject to damage, as it is capable of increasing thelaser light intensity 100.000 times by its focusingpower at the retina.Parallel rays of a laser may be focused to a point image by the eye while rays from aconventional lamp can produce a sizeable and less dangerous image at the retina.

. The skin is usually much less sensitive to laser light than the eye but with everincreasing laser intensities encountered, skin damage is becoming a concern.

ExposureExposure LimitsLimits


UnitsThe unit used to describe the radiation exposure from laserradiation are Watts ( W ) or milliwatts (mW ) for thepower or W/m2 or mW/cm2 for the intensity.

The exposure limits (ELs)Exposure at levels below the ELs should not result in adversehealth effects.

Should be used only as guidelines for controlling human exposureto laser radiation. They should not be regarded as thresholds ofinjury or as sharp demarcations between "safe" and "dangerous"exposure levels.


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ClassificationClassification


The hazard classification specified for laser aredefined by the output parameters, i.e. emissionwavelength, emission duration, power output, andaccessible emission levels (AELs) of laser radiation.

ClassificationClassification UNE EN 60825-1 /A2: 2002

Class 1 Safe under all conditions of normal use. CD-ROM players

Class 1MSafe for all conditions of use except when passed through magnifyingoptics such as microscopes and telescopes.

Class 2Safe because the blink reflex will limit the exposure to no more than 0.25seconds. It only applies to visible-light lasers (400700 nm) Supermarket scanners

Class 2M Safe because of the blink reflex if not viewed through optical instruments.

Class 3R Considered safe if handled carefully, with restricted beam viewing. L. pointers

Class 3BHazardous if the eye is exposed directly, but diffuse reflections such asthose from paper or other matte surfaces are not harmful. Research

Class 4

Highest and most dangerous class of laser. Can burn the skin, or causedevastating and permanent eye damage. May ignite combustible materials(fire risk). These hazards may also apply to diffuse, indirect or non-specular reflections of the beam, even from apparently matte surfaces,meaning that great care must be taken to control the beam path .

Research /industry



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WarningWarning SignsSigns andand IPEsIPEs

LaserLaser RadiationRadiation HazardsHazardsProtective eyewear

,,

must be selected for the specific typeof laser, to block or attenuate in theappropriate wavelength range.

Eyewear is rated formaximum power rating

or optical density(absorbance), in thespecified wavelengthrange.

A = log10 (Io/I1)

WarningWarning SignsSigns andand IPEsIPEs

8.0.02

8.1.02C


,,


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LocationLocation ofof LaserLaser BeamsBeams atat INAINA

Lab Instrument Fabricante y Modelo (nm) / P (W) Clase8.0.02 PLD Neocera - ThinFilmStar 248nm / 25W Class 4

8.1.01CPirlisis lser Rofin 9-12m / 500W Class 4

Lser 808m / 10W Class 4

8.0.03 B

AFM Nanotec 635nm / 1 mW Class 2

AFM Veeco 690nm / 1mW Class 2M

DPN NanoInk DPN500 670nm / 5mW Class 3R

8.1.03 laser 1047 - 1053 - 1064 nm / > 0.5 W Class 4

7.2.02 Micro-Raman Witec

Witec 488nm / -- mW Class 3B

Witec 532nm / -- mW Class 3B

Research Electro Optics 633nm / 35mW Class 3B

TOPICA Photoionics 785nm/


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IonizingIonizing RadiationRadiation HazardsHazards

Hand mit Ringen

22th December 1895

Hand with Rings, a print of oneof the first of WilhelmRntgen's X-ray photographs.It shows the left hand of hiswife, Anna Bertha Ludwig

Radiation: is a process in whichenergetic particles or energetic wavestravel through vacuum, or throughmatter-containing media that are notrequired for their propagation

Ex.: electromagnetic waves (UV, X, IR, visiblelight) & corpuscular radiation (neutrons, )

Radioactivity: spontaneous emission ofradiation as a result of nuclear instability.

Ionisation: is an electrical process inwhich an electron is knocked out of itsorbit.

Definintions


Ionising radiation: is radiation that is energetic and capable of causing atomsand molecules in its path to split into positive and negative ions.

electromagnetic spectrum


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TYPES OF IONIZING RADIATION

1.- Directly Ionizing:

Any charged massive particle can ionize atoms directly through Coulomb forcesif it carries sufficient kinetic energy (moving at relativistic speeds).This includes atomic nuclei ( radiation: 4He nucleus) , electrons (radiation), muons, charged pions, and protons (main component of naturalcosmic rays).

2.- Indirectly Ionizing:

- Photons: They can ionize atoms through the Photoelectric and Comptoneffects. Those interactions will eject an electron at relativistic speeds, turning itinto a -particle that will ionize many more atoms.

X-rays (100eV 100keV) & -rays (100keV)

- Neutrons: fast neutrons will interact with the protons in hydrogen and thismechanism produces proton radiation (ionizing).


sheet of paperOuter layers of the skin

aluminum plate1-2 cm of living tissues

lead shield

blocked using lightelements, like hydrogen

Inter

action

Penetr

ation

+

-

-

+


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Definitions &Units

Absorbed dose: energy that is absorbed bya unit of mass that is irradiated with sometype of radiation of some magnitude. The SIunit is gray(Gy), J/kg.

Equal absorbed doses of different types of ionizingradiation cause different amounts of damage toliving tissue. Therefore,

Equivalent dose: was defined to give anapproximate measure of the biological effectof radiation. It is calculated by multiplying

the absorbed dose by a weighting factor WR,which is different for each type of radiation.The SI unit is sievert(Sv) , J/kg.

Different tissues and organs have varyingsensitivity to radiation exposure. Therefore


Radiation WR

Photons, 1

Electronsmuons

1

Neutrons 5 - 20

Protons (>2Mev) 2

particles,nucl fision products,heavy nucleous

20

Weighting Factors WR

Effective dose: refers to dose averaged over the entire body and takesaccountf or the relative sensitivities of the different tissues exposed.

(NTP614: Radiaciones Ionizantes. Normasde proteccin.)

Source Natural

. Natural radioactive materials

. Cosmic Rays

Artificial. Artificialy produced radioisotopes

. X-ray tubes & particle accelerators


The average person in Spainreceives an effective dose of3.5 mSv / year(2.4 mSv/year correspondingto natural sources).

Source: Consejo de Seguridad Nuclear (CSN)


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Exposure

Type

Contamination

Radioactive contamination occurs when radioactivematerial is deposited on or in an object or a person. Acontaminated person has radioactive materials on(external c.) or inside their body (internal contamination)The person remains exposed to radiation until theradionucleides are eliminated or radioactive activity decays.

Irradiation

A person exposed to radiation is not necessarilycontaminated with radioactive material. A person whohas been exposed to radiation has had radioactive wavesor particles penetrate the body, like having an x-ray.


HazardsHazards


Deterministic effects:

. They reliably occur above a thresholddose.. Their severity increases with dose.

If number of destroyed cells is high, thecorresponding tissue or organ will resultdemaged.

Stochastic effects:

. Their probability of occurrenceincreases with dose.

. The severity is independent of dose.

. There is no a threshold dose.

When the irradiation is not lethal for the cell,much of the radiation induced demage isrepaired by cellular mechanisms. When repair isincomplete or misrepairoccurs, the geneticdemage can lead to the induction of cancer

- Ionizing radiation liberates e- in matter leading to the creation of freeradicals (very reactive) responsible for demage of cells -


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Safety Procedures

1. Reducing exposure (time/distance/shielding)One can never have "zero" radiation exposurebecause of the natural radiation (cosmic rays,

natural isotopes etc.) Therefore, the best we can

do is to add nothing to this background dose. TheALARA approach (As Low As Reasonably

Achievable) is used. Instead of operating at orjust below permissible exposure limits, one must

stay as far below the exposure limits as possible.

RD 783/2001

2. Training and information to workers.

3. Delimitation of areas and signalling.

4. Classification, monitoring and

protection of ocupationally exposed

workers.


ExposureLimits (RD 783/2001)

Safety Procedures. Delimitation of areas and signalling

Controlled area: Controlled areas are designated if it is necessary for persons to enter or work in anarea where special procedures to restrict the possibility of significant exposure are followed. Also if

persons working in this area are likely to receive an effective dose of greater than 6mSv per year or anequivalent dose of greater than 3/10ths of any relevant dose limits in respect of employees aged 18

years or above.

Simple

Limited stay area: Risk to receive an effective dose greater than dose limits. Regulated stay area: Risk to receive in short period of time effective dose greater than

annual dose limits.

Forbiden area: Risk to receive in a single exposure effective dose greater than annual doselimits.

Supervised area: Non controlled areas but persons working in this area are likely to receive aneffective dose of greater than 1mSv per year or an equivalent dose of greater than 1/10ths of anyrelevant dose limits in respect of employees aged 18 years or above.



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Safety Procedures. Delimitation of areas and signalling


Safety Procedures. Clasification of exposed workers



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LAB. EQUIPO Casa Modelo FUENTE RIESGO RAD. MEDIDAS PROTECCIN Observaciones

7.0.05 XRD Bruker D8 AdvanceFuente rX Cu k

60kV, 80mA, 3kWIrradiacin rX

.Blindaje del equipo.

.Sealizacin fuente encendida

Exento

NHM-X160(1)

7.0.05 XPS Kratos AXIS UltraDLDFuentes rX de Al k y Mg k

15kV, 15mA 2.25 kW

Irradiacin rX

Contaminacin (2).Blindaje del equipo.

.Sealizacin fuente encendidaExencion(3)

7.2.01DMADiff. Movility Analizer

Crim 241Am fuente encapsulada 241Am Irradiacin, ,

Zona VigiladaControl dosimtrico de rea

contador Geiger

Instalacin radiactiva3Cat. (5)

8 .0 .0 1 Eva por ado r BocEd war ds Au to5 00 Aceler a e- > 5 kV ( 5.3 keV) I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on(3)

8 .0.01 Dual Beam FEI Helio 60 0Acelera e- > 5kV (30keV)

Acelera Ga3+ > 5kV (30keV)I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on (4)

8 .0.01 Dual Beam FEI Helios 65 0Acelera e- > 5kV (30keV)


7 .0.04 Dual Beam FEI Nova 2 00Acelera e- > 5kV (30keV)


7.0.03 T EM FEI Tecnai T20 Acelera e- > 5 kV ( 20 0k eV) I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on (4)

7.0.04 SEM FEI Inspect F Acelera e- > 5 kV ( 30 keV) I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on (4)

7.0.04 NAP-SEM FEI Quanta 250 Acelera e- > 5 kV ( 30 keV) I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on (4)

7.0.06 T EM FEI Tecnai F30 Acelera e- > 5 kV ( 30 0k eV) I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on (4)

7.0.07 TEM FEI TITAN 60-300 Acelera e- > 5 kV ( 30 0k eV) I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on (4)

7.0.08 TEM FEI TITAN Cubo 60-300 Acelera e- > 5 kV ( 30 0k eV) I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on (4)

8.0.03A MBE DCA M600 Acelera e- > 5kV (15keV) Irradiacin rX Exencion(3)

8.0.02PLD /

SputteringNeocera . Acelera e- > 5 kV ( 20 keV) I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on(3)

8 .0 .0 2 Sp utt er in g AJA I nt. AT C- Or ion Aceler a e- > 5 kV ( XXk eV) I rr adia cin r X Bli nd aj e d el equ ipo Exen ci on(3)

8.1.01 Reactivo

Actetato de Uranilo

Fuente no encapsulada

Emisor radiaciones

Contaminacin

(ingestin, inhalacin,

heridas abiertas)

Trabajoen campana qumica

Uso de doble guante

Gestin de residuos

Guardado en armario detxicos

7.1.01 Reactivo


Acetato de uranilo diluido al 1%


Emisor radiaciones

Contaminacin

(ingestin, inhalacin,

heridas abiertas)

Trabajoen campana qumica

Uso de doble guante

Gestin de residuos

Guardado en la nevera

1. Real Decreto 1836/199 modificado por Real Decreto 35/2008 Anexo I 1e - Exento por resolucin del Ministerio de Economa. Referencia NHM-X160. Indicado con cartel

correspondiente en equipo. Necesarias Revisiones peridicas de verificacin de tasa de dosis y del correcto funcionamiento de sistemas de seguridad. Contrato de

mantenimiento que incluye revisiones semestrales por personal de Bruker

2. Algunos filamentos contiene Torio (radionucleido. Riesgo por contaminacin). Estos elementos slo se manipulan por t cnicos especializados de Kratos.

3. Real Decreto 1836/199 modificado por Real Decreto 35/2008 Anexo I 1d - Exento por trabajar con voltajes V30kV y no presentar tasas de dosis superiores 1S/h en

ningn punto situado a 0.1m de la superficie accesible del aparato.

4. Real Decreto 1836/199 modificado por Real Decreto 35/2008 Anexo I 1d - Exento ser un microscopio electrnico y no presentar tasas de dosis superiores 1S/h en ningn

punto situado a 0.1m de la superficie accesible del aparato. Medicin y revisiones peridicas realizadas por personal de FEI.

5. Supervisor titulado de Instalacin Radiactiva asignado : Virginia Gmez ([email protected])

Ionizing Radiation HazardsIonizing Radiation Hazards

LAB. EQUIPO FUENTERIESGO

EXPOSICINMEDIDAS

PROTECCINOBSERV.

7.2.01

DMADiff.

Movility

Analizer

fuenteencapsulada

241Am

Irradiacin

, ,

Zona Vigilada- Control dosimtrico

de rea

- contador Geiger

Instalacinradiactiva3 Cat. (5)

(5) Supervisor titulado de Instalacin Radiactiva asignado

Virginia Gmez ([email protected])

Ionizing Radiation HazardsIonizing Radiation Hazards


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References. Ionizing Radiation Ley 25/1964. Reguladora de la energa nuclear. Directiva 96/29/ EURATOM por las que se establecen las normas bsicasrelativas a la proteccin sanitaria de los trabajadores y de la poblacin contralosriesgos queresultande las radiaciones ionizantes. Real Decreto 1836/99. Reglamento de Instalaciones Nucleares yRadiactivas. Modificado por el Real Decreto35/2008. Real Decreto 1891/1991. Instalacin y utilizacin de aparatos de rayos Xcon fines de diagnstico mdico. Derogado por el RD 1085/2009 Reglamentosobre instalacin y utilizacin de aparatos de rayos X con fines de diagnsticomdico. Real Decreto 413/1997. Proteccin operacional de los trabajadoresexternos con riesgos de exposicin a radiaciones ionizantes por intervencinen zona controlada. Real Decreto 783/2001. Reglamento sobre proteccin sanitaria contraradiaciones ionizantes. Real Decreto 1066/2001 Reglamento que establece condiciones deproteccin de dominio pblico radioelctrico, restricciones a las emisionesradioelctr icas y medidas de proteccin sani taria f rente a emis ionesradioelctricas. Instruccin de 31/5/2001 n IS-01. Def ine el formato y contenido deldocumento individual de seguimiento radiolgico (carn radiolgico) reguladopor el RD 413/97.

Instruccin de 6/11/2002. Cual if icaciones para obtener el reconocimiento de experto en proteccin contraradiaciones ionizantes.

Instruccin de 26/2/2003 n IS-05. Se definen los valores de exencin para nucleidos segn se establece en lastablasA y B del Anexo I del RD 1836/99. Real Decreto 1546/2004. Plan Bsico de Energa Nuclear. Modificado por el RD 1428/2009. Instruccin de 30/1/2008 n IS-17. Homologacin de cursos o programas de formacin para el personal que dirijael funcionamiento u opere los equipos en las instalaciones de Rayos X con fines de diagnstico mdico y acreditacin delpersonal de dichas instalaciones. Nota Tcnica de Prevencin 589: Instalaciones radioactivas: definiciny normas para su funcionamiento. Nota Tcnica de Prevencin 614: Radiaciones Ionizantes. Normas de proteccin.

StrongStrong StaticStatic MagneticMagnetic FieldFieldSafetySafety

magnetic field of a bar magnet revealed by iron filings on paper


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Strong Static Magnetic FieldStrong Static Magnetic Field

SafetySafety

Magnetic fields are produced by moving electric charges and theintrinsic magnetic moments of elementary particles associated witha fundamental quantum property, their spin.

Static Magnetic Field: when it is constant with time (Frequencyequals to 0 Hz).

Definintions

Strong Static Magnetic FieldStrong Static Magnetic FieldSafetySafety

. The magnetic field (H) describes the field generated by a free current only.

H-field is measured in ampere per metre (A/m) in SI units.

. The magnetic induction (B) describes the field generated by a current plus theeffect of magnetization of a material.

B is measured in Tesla (T) in SI units.

B H

Tesla (T) Gauss (G) Ampere/metre (A/m) Oesterd (Oe)

1 T 1 104 79,6 x 104* 104*

1 G 10-4 1 79,6* 1*

1 A/m 1,257 x 10-6* 0,01257* 1 0,01257

1 Oe 10-4* 1* 79,6 1

Units and magnitudes

* In free air


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Strong Static Magnetic FieldStrong Static Magnetic Field

SafetySafetyUnits and magnitudes

Magnetic Resonance Imaging

0,2 - 3 T

Earth Magnetic Fieldat Earth surface

0,035 - 0,07 mT

Ultra High Field MRI - Research

7 11 T>20 T

HumansAnimals

HazardsHazards


There is a certain relationship between the variation with the time of the intensityof the electric and magnetic fields and the severity of the adverse effects, whichcan be derived from, for the health in persons exposed to them. Health risks arelower when exposed to constant magnetic field.

. In the case of the static magnetic fields, it is only likely that acute effects occurwhen there is movement in the field, such as the movement of a person or body

movement internal (as blood flow or the heartbeat).- A person who travels in a f ie ld of more than 2 T may have feelings of dizziness andnausea, accompanied in some cases by a metallic taste in the mouth, andpercept ions of flashes of light. But these are only temporary, these effects canhave an impact on the safety of the people who perform sensitive operations(such as the surgeons that perform operations on MRI units).

. Static magnetic fields influence the electrical loads to move with the blood, asthe ions, and generate electric currents and fields around the heart and majorblood vessels, which can slightly alter the circulation of the blood. However, theseacute effects tend to occur only in the event of exposure to fields of more than8 T.

- Among the possible effects include slight alterations of the heart beat, and anincreased risk of abnormal heart rhythm (arrhythmia), that can endanger the life ofthe patient (such as ventricular fibrillation).


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HazardsHazards

StrongStrong StaticStatic MagneticMagnetic FieldField

SafetySafety

Special consideration is needed for persons with

. Cardiac pacemakers

. Neurostimulators

. Implantable cardioverter defibrillators

. Active sickle cell anemia

. Ferrous protheses

. Other metallic, electronic, magnetic or mechanical implants ordevices.

Serious injury may result in presence of static magnetic fieldsand exposure limits for this persons are drastically lowered.

STRONG MAGNETIC

FIELD

PERSONS WITH

PACEMAKERS MUST

NOT ENTER THIS AREA

5 GAUSS

ExposureExposure LimitsLimits


IRPA- ICNIRP: lInternational Protection Association - Non-lonizing Radiation CommitteeACGIH: American Conference of Governmental Industrial Hygienists.

Static Magnetic Field. Exposure Limits


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Safety procedures:

Compressed gas cylinders shall be secured at alltimes.

Tools shall be non-magnetic in nature if usedwithin the 100 gauss lines.

Caution shall be taken when working around

magnets if wearing steel-toed safety shoes.

Steel, iron and other magnetic objects shall besecured and fastened down or kept behind the100 G line.


SafetySafetyIndirect Hazards:

Strong magnetic fields may attract (and accelerate) ferrousobjects that are magnetic.


OTHER RISKS:

Potential for physical damage to expensive and sensitiveresearch equipment. Strong magnetic fields may attract tools, dustand particles that are magnetic, and will affect magnetic items such ascredit cards, magnetic tapes or sensitive electronics.

BrukerBiospinGmbH


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StrayStray FieldField PlotsPlots


SafetySafety

WarningWarning SignsSigns

1.- Security Zone: Corresponds to the entirelaboratory that contains magnetic installation.The door of the laboratory should be properlymarked with the corresponding warning signalsof Strong Static Magnetic Field.

-Tour groups and unescorted visitors

SHALL NOT ENTERrooms or areas that containenergized magnets-

2.- Exclusion Zone: It corresponds to the areainside the line of5 Gauss. This line is indicatedin the laboratory by a yellow and black ribbonthat delimits the exclusion zone. No admissionfor persons with pacemakers or other medicalimplants.


5 GAUSS


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* This value represent the maximum available magnetic field at sample holder.Due to instrument design and shielding, magnetic field is highly constrained to theinterior of the instrumentand hence exposure hazard is reduced.

Laboratorio Equipo Fabricante y Modelo Campo mximo*3.1.06 RMN Bruker AMX 300 7.0 T

8.0.05

SQUID Quantum Design 5.0 T

VSM Lakeshore 2.3 T

MFM/STM Attocube(Z) 8.0 T

(XY) 2.0 T

7.1.02B

Time Domain NMR BRUKER Minispec mq 60 1.4 T

VSM VSM-ADE 2.1 T

Magnetotransporte ------------- 1.0 T


SafetySafetyLocationLocation ofof StrongStrong StaticStatic MagneticMagnetic FieldsFields atat INAINA

References. Static magnetic fields NTP 598: Exposicin a campos magnticos estticos (Nota TcnicaPreventiva del Instituto Nacional de Seguridad e Higiene en el Trabajo,INSHT)

REAL DECRETO 1066/2001, de 28 de septiembre, por el que seaprueba el Reglamento que establece condiciones de proteccin deldominio pblico radioelctrico, restricciones a las emisionesradiolctricas y medidas de proteccin sanitaria frente a emisionesradiolctricas.

RECOMENDACIN DEL CONSEJO de 12 de julio de 1999(1999/519/CE) relativa a la exposicin del pblico en general acampos electromagnticos (0 Hz a 300 GHz)

AMERICAN CONFERENCE OF GOVERNMENTAL INDUSTRIALHYGIENISTS (ACGIH). Threshold Limit Values for ChemicalSubstances and Physical Agents. ACGIH Cincinnati. 2002

INTERNATIONAL COMMISSION ON NO-IONIZING RADIATIONPROTECTION. Guidelines on limits of exposure to static magneticfields ICNIRP Guidelines. 1994.

WORLD HEALTH ORGANIZATION-INTERNATIONAL RADIATIONPROTECTION ASSOCIATION. Magnetic fields. Environmental HealthCriteria n- 69. Geneva 1987

POLK, CH and ELLIOT P. Handbook of biological effects ofelectromagnetic fields. CRC Press, inc., 2000 Corporate Blvd. NW.Boca Ratn, Florida, 3341. (1986)


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CryogenicCryogenic liquidliquid hazardshazards

Liquid Nitrogen

KRYOS

cold or freezing

IntroductionIntroduction

CRYOGENICS


GENES

Born or generated

- Cryogenic liquids are liquefied gases that havea normal boiling point below 150C -


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He H2 N2 Ar O2

Boiling point at 1atm (C)

(K)

-269

4.2

-253

20.3

-196

77.3

-186

87.3

-183

90.2

Liquid Density (kg/l) 0.125 0.071 0.808 1.40 1.142

Gas Density at 1atm and 15C (kg/m3) 0.167 0.084 1.17 1.67 1.34

Gas Specific Density (air=1)0.136 0.068 0.95 1.36 1.09

Liquid to Gas expansion ratio749 842 691 836 854

Heat of vaporization (kJ/mol) 0.085 0.449 2.793 6.447 3.410

Type of gas Inert Flammable Inert InertSupport

combustion

PhyisicalPhyisical PropertiesProperties

Cold burns, frostbite &/or hypothermia caused by direct contact with theliquid, pipes, etc. or its low temperature vapors. Delicate tissue, such as eyes,can be damaged by a brief exposure to the cold gas.

Lung lesions breathing very cold gas from the vaporization of the liquefied gas

Low temperature embrittlement (affects most materials more or lesspronunced) / thermal stress giving rise to the emergence of cracks instructures, with danger of collapse.

HazardsHazardsLOW TEMPERATURE

Risk of asphyxiation as a result of an oxygen deficient atmosphere.

Absence of warning properties!!!colourless, odourless & tasteless

A person can become unconscious without any warning symptoms

Pressure build up &/or explosion risk sealed containers / pipes.

LARGE EXPANSION RATIO ON EVAPORATION



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HazardsHazards CryogenicCryogenic liquidliquid hazardshazards

Cryogens

* can freeze you

* can suffocate you

* can cause explosions

FirstFirst AidAid


Frostbite to EYES (generally caused by rapidly evaporating liquid)

Remove worker from the source

Open eyes wide to allow the liquid evaporate.

Flush affected area with copious quantities of cold/tepid water (unheated!)for 15 min.

Contact emergency services and seek inmediate medical treatment.

What to do in the event of


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FirstFirst AidAid CryogenicCryogenic liquidliquid hazardshazards

Frostbite to SKIN (generally caused by contact with liquid or refrigerated metal. In the latter case, theskin can stick to the metal and tear when pulled away)

Contact emergency services and seek inmediate medical attention if contact with the fluid hasresulted in blistering or deep tissue freezing or a reduction in body temperature.

Remove contaminated clothing. (This must be done carefully to prevent salvageable skinfrom being pulled off.)

Remove clothing that may interfere with circulation of blood to afected area

Flush affected area with copious quantities of lukewarm (unheated!) water for 15 min.

- DO NOT USE HOT WATER - DO NOT USE DRY HEAT

- DO NOT RUB (to prevent further damage to skin) - DO NOT APPLY ANY OINTMENTS

Once area has thawed, cover with dry sterile bandages and a large bulky protective coveringuntil paramedics arrive. (This will help prevent further demage to area and infection)

If a large area has been exposed (such that the body temperature is reduced, hypothermia),wrap worker in blankets and wait for paramedical arrival.

What to do in the event of

FirstFirst AidAid


What to do in the event of: Suspected Asphyxiation

Asphyxiation (generally caused by rapid evaporation of liquid)

Rescue:

- If possible (oxygen monitors register >19.5% O2 content in room), remove

worker to air with known oxigen content 20.9%. DO NOT ENTER ALONE!

- If oxygen monitors register


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Only use vessels designed for cryogenic materials, which must be properlyvented.

Never use plastic, glass or rubber with cryogenic materials

Use the freight elevator, not the passenger elevator. Never accompanycryogenic liquid containers in lifts.

Always label the containers.

SafetySafety ProceduresProcedures


Do not handle Cryogenic Liquids before receiving adequate instructionand training. If you are in doubt about what to do, or are untrained in cryogenicliquid procedures, ALWAYS seek the advice of a competent person.

Always use tongs to remove items from liquid nitrogen.

Do not expose bare skin to liquid or its vapours. Do not inhale the vapours.

Always wear the proper protective equipment including:

- a full face shield with goggles

- loose fitting cryogloves.

- proper footwear and clothing.

Cryogenic liquids must be handled and stored in well ventilated areas. Wherethis is not possible, oxygen monitor must be installed. Always allow excess liquidto evaporate in a fume hood or in a well ventilated area.

SafetySafety ProceduresProcedures


Dewar content [l] < laboratory content [m3] / 4


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19.519.523%23% SafeSafe rangerange

andand faintingfainting afterafter a short timea short time,, oftenoften withoutwithoutpriorprior warningwarning

, nausea,, nausea, vomitingvomiting


LN2Explosion


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QUENCHQUENCH -- VIDEOSVIDEOS

QUENCHQUENCH -- BRUKERBRUKERQUENCHQUENCH

Rancho Feb. 2009Rancho Feb. 2009


Cryogenic tanks are designed to keep heat away from the liquidcontained inside the vessel.

They are constructed like a vacuum bottel

Since heat leak is always present vaporisation takes placecontinuously.

Usually are equiped with safety relief valves and rupture disks

CRYOGENICCRYOGENIC CONTAINERSCONTAINERS


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Dewar

flask

LHe

Cylinder

Cryostat

LN2

Cylinder


CRYOGENICCRYOGENIC CONTAINERSCONTAINERS Contens gaugeIndicates aproximate level of liquid

Pressure Gauge

Displays internal pressure of the container

Vent Valve

Primarily used to vent the vapour space while

filling. Can be used to vent unwanted pressureduring storage/use

Liquid Valve

Liquid is withdrawn through this valve

Pressure Relief Devices

Protect vessel from over-pressure

(1) Re-seating spring-loaded relief valve

Low P. 22 psig (for dispensing liquid)

High P. >230 psig (for dispensing liquid and gas)

(2) Burst disk rated to protect the inner vessel.

Warning!!

Never plug, restrict, cap, seal

or remove any relief device


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Hearing a slight hiss from a liquid cylinder is usually the normaloperation of its pressure relief device

- Liquid is converted to gas at about 2.3% per day even under ideal container conditions-

Ice or frost buildup on a pressure relief valve can be removed with adamp cloth (use appropiate PPE)

Rupture of the backup disk may release a large quantity og liquid andgas. Evacuation of the area is required to prevent asphyxiation.

If there is a large spill or rupture of the container -. Evacuate!

Warning signs of a damaged dewar

Continuous venting from vent valve could mean there is dirt in the ventvalve or it is demaged

Sweat or frost at the bottom or sides of the dewar is an indication of ademaged vacuum jacket

Lab Equipo Fabricante LHe / LN2 Observaciones3.1.06 RMN Bruker AMX 300 LHe / LN2 Superconducting coil*

8.0.05

SQUID Quantum Design LHe Superconducting coil*

VSM Lakeshore LHe & LN2 Continuous flux

MFM/STM Attocube LHe Superconducting coil*

7.1.02B Magnetotransport ------------- LHe / LN2 Continuous flux

7.0.01 SPM Specs LHe & LN2 Cryostat7.0.02 SPM Omicron LHe & LN2 Cryostat

3.2.02 Xtales liq. y polim varios LN2 varios

7.0.03 TEM 200 FEI LN2 EDX / Continuous flux

7.0.04SEM FEI LN2 EDX

DB-Cryo FEI LN2 EDX / Continuous flux

7.0.06 TEM 300 FEI LN2 EDX

7.0.07 Titan Low Base FEI LN2 EDX

7.0.08 Titan Cube FEI LN2 EDX

7.1.01 Prep. Muestras varios LN2

8.0.01 DB (x2) FEI LN2 EDX

8.1.05 Cultivos celulares --- LN2 dewar

P 7.0 Carga/descarga dewards

* Quench risk


LocationLocation ofof LHeLHe && LNLN atat INAINA


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References. Cryogenic Liquids1.- www.carburos.com

2.- www.es.airliquide.com

3.- www.praxair.es

4.- NTP 383: Riesgo en la utilizacinde gases licuados a baja Temperatura

5.- Safe Handling & Use of liquid Nitrogen and Other CryogenicGases. Laboratory safey training. Office of Engineering safety.Dwight Look College of Engineering. Texas Engineering Experimental

Station.

6.- Introductionto CryogenicEngineering 5. -9.12.2005 G. Perini,G. Vandoni, T. Niinikoski, CERN

7.- Cryogen safety. C.L. Dennis, Metallurgy Division, MSEL, July 2009.Adapted for use at the NCNR by Scherschlig

seguridadina rf vs03

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