Transcript laser-Non ionizing R.. - Florida International University

Non Ionizing Radiation Safety
and Chemical Safety
SK Dua, Ph. D., CHP, CLSO
Bill Youngblut, MS, CIH, CSP
Environmental Health & Safety
Florida International University
Conceptualization
Get EH&S, and engineering professionals involved
as early as possible.
 Before submitting grant proposal or budget.
 Help identify and correct potential problems.
 Time line issues for local, state, and federal
safety & environmental permits.
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Avoid
Avoid
Avoid
Avoid
budget over runs
construction delays
process startup delays
fines
Conceptualization…
EH&S professionals involved should
include:
 Safety Engineer
 Fire Safety
 Environmental (Air, Water & Waste)
 Radiation & Laser Safety Officer
 Industrial Hygienist
Disposal & Recycle
Environmental impact of battery and printed circuit
board manufacturer and disposal.
 Heavy Metals (Lead, Silver, Gold, Platinum,
Mercury, Copper)
 Solders, Flux Solder & Flux residues
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Rinse water residue
Airborne concentration levels in manufacturing
Contain metals, resin
Consult manufacturer or MSDS for more information
Batteries: Acids, lead
Circuit board substrate: Beryllium
ORGANIZATION CHART: MANAGEMENT:
IONIZING AND NON-IONIZING RADIATION
PROGRAM
Senior Management: Vice President of Research
Alternate: Director, EH&S
Chairperson Radiation/Laser Safety Committee
Safety Committee
Establish operating policies, practices and procedures for
compliance with the regulations. Review proposals, reports,
procedures, conduct program audit. Communicate with
RSO/LSO
Radiation/Laser Safety Officer
Reports to Dir., EH&S, Manages day-to-day program activities,
Submits proposals, reports, procedures, reviews to Committee for
approval/comments/vote
Authorized users and workers
Comply with posting and labeling requirements
Follow safe practices and procedures
Ionizing vs. Non-ionizing Radiation
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Ionizing Radiation
– Higher energy electromagnetic waves (X- gamma)
or particles (alpha beta)
– High enough energy to pull electron from orbit
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Non-ionizing Radiation
– Lower energy EM waves (laser, radio & TV
broadcasting, cell phone, pagers, satellite,
Microwave ovens, Power lines, Physical therapy- RF
Diathermy
– Not enough energy to pull electron from orbit, but
can excite the electron
Laser Components
Laser Devices
The laser is a device, which produces a
very intense and very narrow (collimated)
beam of electromagnetic radiation in the
wavelength range 180 nm to 1 mm.
 Laser devices are ranked by class (1, 2,
3a, 3b and 4) according to their energy or
power, and hence, their potential to cause
injury.
 Laser radiation exposure can cause injury
to:
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– Eye and skin
Laser Warning Signs and Symbols
American National Standards Institute
International Electro Chemical Society
Posting Warning Signs
The entrance door shall have laser label
with warning sign and laser class.
 The entrance door shall have hazard
identification chart.
 The entrance door to the laser lab shall
have lighted sign, “Laser in Use” whenever
laser is turned on. Work Management can
arrange to install the signage. Expenses
will be borne by the Department/PI.
Whenever laser is in use visual or audible
warning devices should be turned on.
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Laser Safety- Controls
 Engineering
Controls
 Administrative and Procedural
 Protective Equipment
Engineering Controls
Protective Housings (All Classes).
 Interlocks on Removable Protective
Housings (All Classes)
 Key Control (Class 3b or Class 4)
 Viewing Windows, Display Screens, and
Collecting Optics
 Remote Interlock Connector (Class 3b
or Class 4)
 Beam Stop or Attenuator (Class 3b or
Class 4)
 Warning Signs
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Administrative and Procedural
Controls
Post laser warning signs.
 Standard Operating Procedures (Class 3b
or Class 4). SOPs for class 4 shall be
developed, documented, reviewed and
approved by Laser Safety Officer
 Output Emission Limitations
 Education and Training (Class 3b, or Class
4).
 The laser shall have emergency shut off. It
is preferred to have shut off both near the
laser device and at a remote console
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Administrative and Procedural
Controls… Laser Beams
Laser beams, direct/diffused shall be
properly shielded to prevent inadvertent
exposure of eyes or skin.
 All beam alignments shall be performed at
low power (class 1).
 When the lab door is opened the laser
should either be shut off or reduced in
power or should be adequately shielded to
prevent injury.
 Laser beams should not be at eye levelwhile standing or seated.
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Procedures
– On-line Laser Safety Training
– Laser Purchasing Procedure
– Laser Registration with the State
– Laser Laboratory Inspection
– Laser Research Proposal Review
– Eye Examination
– Beam Alignment
– Laser Operation
Protective Equipment
 Suitable
personal protective
equipment, e.g., eye protection
glasses suitable for the laser
power/energy and wavelength, will
be used.
 Beam shutters/shields shall be
available where required.
Bioeffects
Photochemical vs. Thermal Limits
 Shorter
wavelengths in the visible (400
to 600 nm) can produce chemical
changes in retinal tissue destroying its
functionality. These changes can occur
for longer exposures and at lower levels
than thermal burns. Photochemical
sensitivity decreases with increasing
wavelength. Both limits must be
evaluated in classifying a product in the
photochemical wavelength range.
Laboratory Accidents
60% of laser accidents in the research
setting happen during laser alignment,
beam manipulation
 Almost all without the user wearing laser
protective eyewear
Why?
 Open beams
- During alignment
- Flexibility in calibration procedures
- Experimental set up changes
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Some famous quotes from the laser users
who do not comply with the safety measures
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“Don’t insult my intelligence.”
“I’ll get it the work done one way or the other.”
“That can’t happen to me.”
“15 years working with lasers and I haven’t had an accident
yet.”
“Nothing bad will happen.”
“Hey I have two eyes”
“Trust me”
“I know where the beam is”
All incidents should be investigated to enhance the
environment, safety, health and quality, prevent recurrence,
and reduce the possibility of severe trends
Laser Safety- Non-beam Hazards
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Electrical Laser Generated Air Contaminants
(LGAC)
Collateral and Plasma Radiation
Optical Radiation
Fire
Explosion
Compressed Gases
Laser Dyes
All non-beam hazards shall be identified and
prevented.
Electrical Hazard
Many laser systems use high voltage and high
current electrical power. Reports of electrical
shock, both fatal and non-fatal can be found for
research, medical, and industrial settings.
Preventative measures
 No Fluids used or placed near the laser system
 Label the laser system with the electrical rating,
frequency and watts
 Proper grounding for metal parts of the laser
system
 Assume all floors are conductive when working
with high voltage
Electrical HazardPreventative measures…
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Provide such safety devices- rubber gloves and
insulating mats
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Combustible components of the electrical circuit are
short circuit tested
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Avoid Contact with electrical components. Capacitors
that can contain electrical charge even after the laser
is powered off. Discharge, short and ground each
capacitor before accessing the capacitor area
Inspect capacitor containers for deformities or leaks
Avoid wearing rings, metallic watchbands and other
metallic objects when working near high voltage
environment
Prevent explosions in filament lamps and high
pressure arc lamps
Electrical HazardPreventative measures…
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Include in regular inspection verification of the
integrity of electrical cords, plugs, and foot pedals
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Only qualified persons authorized to perform service
activities access laser’s internal components
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Do not work alone
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When possible, only use one hand when working on a
circuit
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Develop and implement lockout/tagout procedures
Laser Generated Airborne
Contaminants (LGAC)
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High power lasers (beam irradiance of hundreds
of W/cm2) upon interaction with substrates may
generate aerosols, gases and vapors, called
LGAC. These contaminants may adversely affect
health, environment and materials, and must be
controlled.
LGAC are controlled by using proper air filtration
systems. Local exhaust ventilation systems can
effectively capture the air contaminants in close
proximity to an emission source. General
ventilation is used to reduce the concentration of
the air contaminants not removed by the LEV.
Collateral and Plasma Radiation
 X-radiation
may be generated from
electronic components of the laser
system, e.g., high voltage vacuum
tubes (> 15 kV) and laser-metal
interactions.
 Plasma emission created during
laser-material interaction may
contain sufficient UV and blue light.
Optical Radiation Hazard
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There are several sources of optical radiation emissions
which can cause eye injury and skin burn:
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Ultraviolet light from discharge tubes
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Visible / infrared light from pumping lamps
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Blue light and UV emissions from interactions between high
power laser beam and target material
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Intense bright light and thermal emissions from laser
welding
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Preventative measures:
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Shield the optical radiation by proper enclosure.
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Wear suitable personal protective equipment to protect
eyes and skin.
Fire Hazard
A fire can occur when a laser beam (direct or reflected)
strikes a combustible material such as paper
products, plastic, rubber, human tissues, human hair
and skin treated with acetone and alcohol-based
preparations. The risk of fire is much greater in
oxygen-rich atmospheres.
The three components required for a fire to start are:
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1) a combustible material
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2) an oxidizing agent
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3) a source of ignition
Keep these components physically separated
from each other.
Explosion Hazards
Sources:
 High pressure arc lamps, filament lamps
and capacitor banks in laser equipment
- Enclose in housing
 Metal dust collected in ventilation systems
- Maintain properly
Compressed Gases
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Hazardous gases (Cl2, F, HCl HF) are used in laser
applications. Develop SOP for safe handling.
Safety problems with compressed gases:
 Free standing cylinders not isolated from
personnel
 No remote shut off valve
 Incorrect labeling of cylinders & gas lines
 Gases of different categories not stored
separately
 No leak testing - Loose gas line fittings
Laser Dyes and Solvents
These complex fluorescent organic compounds in solution with
solvents form a lasing medium.
Concerns:
 Dye Powders
– Carcinogens (benzo(a)pyrene);
– Toxic
 Little or no toxicity data
 Before mixing with solvent, concentrated dye
powder inhalation or skin contact hazard
 Dye Solvents – chemical and physical hazards:
– Transport dissolved substances through the skin
– Flammable (Chlorobenzene, Cyclohexane, Methanol)
– Toxic (Benzonitrile, Dioxane, Dimethylformaldehyde)
– Carcinogenic (Chloroform, Dichloroethane,
Tetrahydrofuran)
Caution
Radiofrequency Energy
Electromagnetic Fields
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Whenever there is electricity, there are: electric
and magnetic fields, these are invisible lines of
force created by the electric charges.
Electric field (unit V/m) exists near an appliance
that is plugged into and electrical outlet (even if
it is turned off). Increases in strength with
voltage.
Magnetic field (unit A/m, Gauss or Tesla) results
from the flow of current through wires or
electrical devices and increases as the strength of
current increases.
Electromagnetic Fields…
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Electric field can be easily shielded or
weakened by conducting objects
Magnetic fields are not weakened and
pass through most materials and are most
difficult to shield.
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Both fields weaken with distance from the
source.
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Line sources of magnetic Field 1/d2
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Point sources of magnetic Field 1/d3
Maximum Permissible Exposure Limits
Power line magnetic lines are ELF rage of spectrum