By: Vince McLeod, CIH and Glenn Ketcham, CIH
Issue: Summer 2004
During the controlled chaos of scene investigation
and recovery, identification, analysis and research experiments,
worker health and safety can get overlooked or pushed to a back burner.
Understanding the required Occupational Safety and Health Administration
(OSHA) programs and recognizing hazards will help you to identify
and correct many of the common safety and health hazards associated
with doing forensic analysis and research.
This column is an introduction to the “Safety Guys” and
OSHA safety and health concerns related to typical forensic laboratories
and associated activities such as scene investigation and recovery.
An overview of common health and safety hazards is presented. Future
columns will provide more in-depth coverage of topics such as hazard
communication and the OSHA Lab standard; bloodborne pathogens;
proper selection and use of personal protective equipment; different
types, setup and operation of biological safety cabinets, chemical
fume hoods and local exhaust ventilation; thermal stress during
scene recovery and ergonomic issues to name a few. The authors
encourage your feedback and questions.
Employers have an obligation to provide a workplace “free
from recognized hazards.” There are many specific OSHA standards
that may apply to forensic laboratories. Some examples are hazard
communication, hazardous chemicals in laboratories, respiratory
protection, electrical safety, and fire safety. Besides the legal
requirements, a safe workplace makes sense as employees are our
most valuable resource.
Different Types of Hazards
An important first step in protecting worker health and safety
is to recognize workplace hazards. Most hazards encountered fall
into three main categories: chemical, biological, or physical.
Cleaning agents and disinfectants, drugs, solvents, paints, and
compressed gases are examples of chemical hazards. Potential exposures
to chemical hazards can occur both during use and with poor storage.
Biological hazards include potential exposures to blood and body
fluids, allergens, infectious zoonotics (animal diseases transmissible
to humans), and other agents such as viral vectors. Blood and body
fluids, ubiquitous in forensic laboratories, are one of the most
important health hazards.
Finally there are the physical hazards associated with forensic
laboratories. The most obvious are slips and falls from working
in wet locations and the ergonomic hazards of lifting, pushing,
pulling, and repetitive tasks. Other physical hazards often unnoticed
are entering confined spaces or trenches, electrical, mechanical,
acoustic, or thermal in nature. Ignoring these can have potentially
serious consequences.
Chemical Hazards
Use of chemicals in forensic laboratories is inevitable and the
potential for harm or injury could be significant if they are misused
or mishandled. OSHA developed two standards to help mitigate these
potential problems: Hazard Communication (29CFR1910.1200) aka “Haz
Comm” and Occupational exposure to hazardous chemicals in
laboratories (29CFR1910.1450) aka the “Lab Standard.” Haz
Comm, formerly known as the “Right-to-Know,” deals
with employers' requirements to inform and train employees on chemicals
present in their workplace. It is one of the most frequently cited
OSHA violations, which attests to both the importance given to
its implementation and, paradoxically, a failure of employers to
fully comply with its requirements.
A written program is the first step and describes how the Hazard
Communication Standard (HCS) will be implemented in the facility.
The other basic tenants of the Hazard Communication Program (HCP)
include maintaining a chemical inventory and associated material
safety data sheets (MSDS), ensuring proper labeling of all chemical
containers and fully training employees prior to work assignments
and whenever the hazard changes. MSDS must be immediately available
and employees must know where and how to find them. They are vitally
important in emergencies and should be carried to the emergency
room with the patient in the event of an exposure. Inadequate or
incorrect labeling is a source of many accidents and exposures
and a common OSHA citation. Clearly label all chemical containers
with the contents and appropriate hazard warnings.
Sterilents, Preservatives, and Cleaning Agents
Sterilents and preservatives are frequently used in forensic laboratories.
Formaldehyde is one of the most common and usually found mixed
with alcohols or phenols. OSHA has a specific standard for formaldehyde
(29CFR1910.1048) that stipulates requirements for initial and periodic
monitoring, protective equipment and clothing, training, and designating
regulated areas among others. A qualified industrial hygienist
should conduct hazard evaluations and exposure assessments if these
chemicals are used. Monitoring can be done with a portable infrared
spectrophotometer or sorbent tubes and pumps.
Other chemicals include embedding agents such as methyl methacrylate
and cleaning materials such as ammonia, sodium hypochlorite, sodium
hydroxide, and hydrogen peroxide. Fumes and vapors from these chemicals
are toxic and corrosive. Take care to prevent skin contact and
inhalation of vapors.
Improper Storage
Frequently encountered chemical hazards include improper storage
(e.g. mixing incompatible materials in the same area; incorrect
labeling of containers), use of unapproved containers for flammable
storage and blocked and untested safety showers and eyewash stations.
Pay attention to chemical storage. Keep acids and bases isolated
and keep corrosives and organic solvents in separate areas. Use
only UL approved containers that have self-closing lids and flame
arrestors for storing flammable liquids. Make sure safety showers
and eyewash stations can be accessed immediately and that they
are tested routinely.
Biological Hazards
Potential exposure to blood, body fluids, and unpreserved soft
tissue are the most important health hazards encountered by forensic
laboratory workers. Pathogens of primary concern when working with
human remains are human immunodeficiency virus (HIV) and hepatitis
B virus (HBV). Other pathogens include arenaviruses, Creutzfeldt-Jakob
disease, filoviruses, herpes, smallpox, viral hemorrhagic fever,
and non-HBV hepatitis.1
Recovery operations present a different set of biohazards including
disease vectors such as insects and rodents, bird and bat excreta
and soil organisms. Examples include histoplasmosis from bird or
bat excreta, coccidomycosis from soil fungi, Lyme disease from
ticks, and hantaviruses transmitted by rodents.
The best control method for potential exposures is with Universal
precautions and ventilation. Universal precautions, developed in
OSHA's bloodborne pathogen standard, aim to reduce skin contact
with biological material by using gloves, lab coats, approved particulate
respirators, and/or face shields. Perform manipulations within
ventilated hoods or safety cabinets when possible. Avoid wearing
street clothes while working with remains and leave work clothes
at the workplace. Make sure work areas are kept clean. Use absorbent
pads to minimize vapors, dust, and particulates.
Physical Hazards
Forensic laboratories inherently have significant physical hazards
present. Included here are electrical safety hazards, ergonomic
hazards associated with material and equipment use, and lifting,
handling sharps, and basic housekeeping issues. Hazards exist in
the field entering confined spaces, trenches, or areas where falls
could occur.
Housekeeping
Many injuries stem from poor housekeeping. Slips, trips, and falls
are very common yet easily avoided. Start with safe and organized
storage areas. Material storage should not create hazards. Boxes,
containers, etc., stored in tiers should be stacked, blocked, interlocked,
and limited in height so that they are stable and secure against
sliding or collapse. Keep storage areas free from accumulation
of materials that could cause tripping, fire, explosion, or pest
harborage.
Material Handling
Forensic laboratories necessitate organization and lots of material
handling. Moving, sorting, and cataloging are daily activities.
Evaluate each of these tasks to eliminate poor ergonomics. Factors
that affect the likelihood of injury are repetition, poor lifting
angles, and awkward posture. Train workers to recognize these factors
and to avoid changing elevation and twisting while lifting. Take
time to observe workers occasionally and try to spot poor techniques
or methods of material handling. Consider contracting with a qualified
professional to perform an ergonomic survey if necessary. Use mechanical
lifting and carrying devices such as pallet jacks and hand trucks
whenever possible. Make sure floors are smooth and free of cracks
or lips that could catch or trip. Inspect carts, hand trucks, and
other equipment routinely to ensure good mechanical condition.
Pay special notice to the castors.
Electrical Hazards
Electrical hazards are potentially life threatening yet are found
much too frequently. First, equip all electrical power outlets
in wet locations with ground fault circuit interrupters, or GFCI,
to prevent accidental electrocutions. GFCIs are designed to “trip” and
break the circuit when a small amount of current begins flowing
to ground. Wet locations usually include outlets within six feet
of a sink, faucet, or other water source, and outlets located outdoors
or in areas that get washed down routinely.
Another very common electrical hazard is improper use of flexible
extension cords. Do not use these as a substitute for permanent
wiring. The cord insulation should be in good condition and continue
into the plug ends. Never repair cracks, breaks, cuts, or tears
with tape. Either discard the extension cord or shorten by installing
a new plug end. Take care not to run extension cords through doors
or windows where they can become pinched or cut. And always be
aware of potential tripping hazards when using them. Use only grounded
equipment and tools, and never remove the grounding pin from the
plug ends. Also, do not use extension cords in series; just get
the right length cord for the job.
As a final check for possible electrical hazards, look over your
lighting. Protect all lights within seven feet of the floor to
guard against accidental breakage. Slip plastic protective tubes
over florescent bulbs prior to mounting or install screens onto
the fixtures.
Compressed Gas
Use of compressed gas cylinders present many unique hazards and
could be a topic for another whole article. Here are a few quick
pointers. Store cylinders safely. As with chemicals segregate them
according to compatibility. In addition, secure cylinders from
tipping or being knocked over. Generally, this means fastening
them to stands or against a wall or cabinet. Remember to turn them
off at the cylinder valve when not in use. Finally, remove the
regulators and install protective valve caps before moving.
Sharps
Sharps containers are ubiquitous in forensic laboratories and
following a few safety rules can help prevent getting stuck with
accident reports. Use only puncture-proof and leak-proof containers
that are clearly labeled. Train employees never to remove the covers
or attempt to transfer the contents. Make sure they are only used
for “sharps” and they get replaced when three-fourths
full to prevent overfilling.
Lockout/Tagout
Areas where one must enter to retrieve evidence or remains might
include machines, vaults, elevator shafts, etc. that could cause
injury if accidentally energized. To protect employees from these
hazards lockout/tagout, known as LOTO, will be one of your most
important programs.
During the period 1992-1996 accidents from being caught in machinery
killed almost 750 workers and nearly another 5,000 lost limbs from
amputation.1 Sadly, every one of these could have been easily prevented.
LOTO is a process that will prevent these accidents when followed
correctly.
First, employees are trained to recognize and isolate all the
energy sources for the equipment. The employee(s) entering the
danger zone then lockout or tagout the energy sources by placing
locks on the appropriate switches, valves, circuit breakers, etc.
Each lock is identified as to its owner and has only one key that
stays in the possession of the lock owner. When work is complete
owners collect their energy source locks and the equipment is brought
back online only after all locks have been removed. If an energy
source cannot be locked out then it should be braced, blocked,
or blanked off to prevent release. Your LOTO program should also
detail steps to follow if the task will span more than one work
shift.
Conclusion
Forensic laboratories present many challenges. In the day-to-day
bustle of investigation, recovery, identification and analyses,
worker health and safety can be easily overlooked. However, with
proper guidance, a trained eye, and practice in noticing the mundane,
we can find and correct many common mistakes and prevent illness
or injury. The Internet provides a vast amount of valuable information
easily researched. Begin with the OSHA and ASCLD websites (www.osha.gov,
www.ascld.org) and chances are you will find what you need. Be
diligent and remember “Safety First!”
1. Galloway, Alison and Snodgrass, J. Josh. “Biological
and Chemical Hazards of Forensic Skeletal Analysis,” Journal
of Forensic Sciences, 1998; 43(5): 940-948.
