Lab Specific Safety
Adapted from
Basic Laboratory Methods for
Biotechnology
by Lisa Seidman and Cynthia Moore
Risk Reduction in the Lab
• Reduce presence of hazards
– Eliminate hazardous material when possible
– Substitute less hazardous equivalent
• Reduce risk of inevitable hazards with good lab design
– Remove employee from hazard
– Contain hazard
– Dilute or reduce volume of hazard
• Establish good lab practices for handling hazards
– Provide employee training
– Practice good housekeeping
• Use personal protective equipment
– Provide PPE for all employees
– Monitor and enforce its use
Personal Protection in the Lab
• Begins with proper clothing
– Clothes should cover all parts of the body
– No dangling jewelry or ties
– Avoid excessive jewelry on hands or arms
– Wear fire-resistant clothing that is easily
removable
Personal Protection in the Lab
• Lab Coats are a must
– They are to be worn in the lab at all times, but not in
common areas
– They are designed to provide a barrier against harmful
agents and prevent contamination of street clothes
– They protect experiments from external contaminants
– They should be made of flame resistant and breathable
fabric chosen to fit work hazards and conditions
– They are to be kept fastened at all times
– Should fit well enough to avoid flapping and have sleeves
long enough to protect arms
– They should be laundered regularly and when visibly
soiled
Personal Protection in the Lab
• Shoes
– Should have covered toes and nonslip soles
• Sandals, sneakers, woven shoes to be avoided
– Low heels are more appropriate
– Can be “dirtier” than the floor itself
– Can be “lab-only” or shoe covers may be
worn over street shoes
Personal Protection in the Lab
• Gloves
– Provide a barrier between your skin and potential
contaminants
– Decide what protection is desired before choosing
gloves
– Thickness should be considered
– Various types exist:
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Thin-walled
Heavy rubber
Insulated
Puncture resistant
– Manufacturers provide chemical resistance
information
• Degradation rate
• Permeation rate
• Breakthrough rate
Gloves
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Choosing and using correct gloves is important for safety
Improper glove use increases risk
Always inspect gloves before wearing
Cover cuts or abrasions on hands before donning gloves
Keep fingernails short and smooth
Choose gloves of appropriate size
Watches and rings may increase exposure risk
Change gloves when exposed soiled and often even if you think
they are clean
• Remove gloves in a manner to avoid spreading contaminants from
outside of glove to skin
• Wash hands thoroughly after glove use and between changes if you
suspect contamination
– Unknown contamination of gloves may cause unintentional spread of
hazardous materials
Glove Types
Type
Recommended for
Natural rubber latex
Bases, alcohols, bloodborne pathogens
Natural rubber blends
Same as natural rubber
Polyvinyl chloride (PVC)
Strong acids and bases, salts, otheraqueous
solutions
Neoprene
Oxidizing acids, phenol, glycol ethers
Nitrile
Oils, aliphatic chemicals, xylene,
bloodborne pathogens
Butyl
Gases, aldehydes, glycol ethers, ketones,
esters
Polyvinyl alcohol (PVA)
Aliphatics, aromatics, chlorinated solvents,
ketones (except acetone), esters, ethers
Fluoroelastomer (Viton)
Carcinogens, aromatic and chlorinated
solvents
Norfoil (silver shield)
Use as glove liner, good for emergency use in
chemical spills
Eye Protection
• Includes safety glasses, goggles, face shields
– Regular glasses are not a substitute
• According to OSHA, 60% of individuals receiving eye
injuries were not wearing protection at all
– Remaining 40% not using appropriate devices
• Small flying particles most common
• 20% of injuries caused by chemicals
• OSHA requires eyewear that:
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Protects against hazards found in that workplace
Fits securely and is reasonably comfortable
Is clean and in good repair
Meets impact resistance and other standards
• Emergency eye wash must be located within 25 feet of
lab area in case of accidental exposure
Hazards Requiring Eye Protection
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Explosion or flying particles
Glassware under vacuum
Compressed gases
Corrosive liquids
Cryogenic materials
Liquids that may splash into eyes
Blood and other body fluids that may aerosolize
Radioactive materials
UV light and other radiation
Ear Protection
• Includes earplugs and earmuffs
• Noisy equipment makes sounds that can
be uncomfortable or hazardous and
require protection
• Long-term unprotected exposure to high
noise levels can lead to hearing loss
Respiratory Protection
• Masks filter dirt and large particles and provide splash
protection
– Most personnel use surgical-type masks
• Air-purification or filtration respirators are needed for
infectious droplet or aerosol precautions or when toxic
materials are present
– Self-contained breathing apparatus in specialized situations
• SCBA contains its own air supply and is used where highly toxic
gas exposure could occur
– Respirators are designed to reduce airborne hazards by
manipulating the quality of air supply
• Require training to use or may be used incorrectly
• Required by OSHA when toxic fumes or hazardous air
contaminants cannot be removed from the environment by other
means
– Air purification respirators filter room air through canisters of
adsorbant materials that remove specific contaminants from the
air
• Require fitting procedures to be effective
Physical Hazards in the Lab
• Glassware and sharp objects
– One of most common injuries is cut from broken glass
– Inspect glassware for cracks and chips before washing
and before use
– Damaged glassware should be repaired or discarded
– Always wear hand protection when washing glassware
– Sharps are lab items like needles and razor blades that
can cause cuts or lacerations
– All sharps and broken glassware are to be disposed of
appropriately
Compressed Gases
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Used by certain pieces of equipment
Stored under high pressure in metal tanks
Gases aren’t problem, pressure is
Cylinders should be handled as explosives
Should be stored upright strapped or chained to
wall or other solid surface
• Eye protection should be worn when handling
• Valve should be covered with safety cap when
not in use
Heat and Burns
• Bunsen burners, hot plates and autoclaves can
result in burn injuries or cause fires
• Don’t leave uncontrolled heat sources unattended
• Leave a note when hot plates turned off
• Use tongs or insulated gloves to handle hot
beakers and flasks
• Never heat sealed containers
• Be careful around superheated liquids, they have
been heated past boiling without releasing the
gaseous phase
Fire
• A chemical reaction between fuel and oxygen
requiring heat or other ignition source
– Fuels are any flammable materials
• Substances that will ignite and burn readily in air
• Commonly caused by ignition of flammable
organic liquids and vapors
– Limiting use and storage of flammable materials can
help reduce fire risk
– Limit open flames and other ignition sources as much
as possible
• Reduce electrical hazards when possible
Cold Hazards
• Due to low temperature freezers, dry ice baths, liquid N2
– Contact with cryogenic substances (temperatures below -78C) may
“burn” skin
• Proper hand and eye protection required when working with cold
• Cryogenic liquids are not compatible with ordinary glassware,
require Dewar flasks
– Heavy multi-walled evacuated metal or glass containers
• Liquid nitrogen supplied in compressed gas cylinders at negative
198˚C
– Can cause third degree skin burns
– Should never be placed in sealed container
• Dry ice should be handled with insulated gloves
– Breathing CO2 vapors could cause hyperventilation or asphyxiation
Lab Electricity Hazards
• Electrical shock is sudden stimulation of body by electricity
when body becomes part of electrical circuit
• Keep equipment in good working order and properly
grounded
– Use GFI circuits that are designed to shut off electrical flow into the
circuit if unintentional ground is detected
• Use caution with high-voltage power supplies and
electrophoresis equipment
• Use only UL approved equipment to lower risk
• Handle electrical equipment only when hands are dry hands
• Unplug equipment when not in use
• Avoid using extension cords
UV Light
• Nonionizing radiation making up the light
spectrum between visible light and X-rays
• Three classes:
– UV-A 325-400 nm “black light”
– UV-B 280-315nm
– UV-C 180-280nm
• Most UV in labs in B and C classes
– Transilluminators for visualizing DNA bands in gels
and germicidal lamps
• Hand-help UV lamps around 254nm
• UV-B and C damage eyes and skin
• Its use requires eye and skin protection
Pressure Hazards
• Due to filtration and other procedures carried out under
vacuum
• Should be done in shielded enclosure in case of implosion
– Collapsing of vessel under low pressure compared with outside
atmosphere
• Use face shield and goggles when working with high vacuum
• Use water aspirators to create moderate vacuum
– Creates a vacuum through a side arm to a faucet with flowing water
– Need a trap for liquid or vapors pulled into the vacuum source
• Autoclaves operate under pressure and heat, producing
multiple risks
Chemical Safety
• The MSDS provides information to use for safe
handling of chemicals
– Lists toxicity, first aid, fire fighting, PPE use, and other
data needed for protection from chemical hazards
• The NFPA ratings on the containers give an idea
of hazards posed by the chemicals
– NFPA ratings include health, flammability, reactivity,
special or specific hazards
NFPA Chemical Label
Picture taken from http://www.nmsu.edu/safety/images/signs/label_NFPA1.jpg