Environmental Health, Safety and Risk Management
University of Alaska Fairbanks
August 2011
1
Overview











Properties and Sources of Benzene
Exposure Limits
Routes of Exposure and Health Effects
Protecting Yourself
Storage
Spills and Exposures
Monitoring
Medical Surveillance
Regulated Areas
Waste Disposal
More Information
2
Properties of Benzene
Benzene
 is a clear and colorless liquid
 is highly flammable (flash point: 12 °F)
 has a sweet aromatic odor
 evaporates readily
 vapors are almost 3x heavier than air
 They can easily travel along the ground to a source
of ignition, causing a fire.
Is slightly miscible in water (0.06% by weight)
 Is slightly lighter than water—thus, some
benzene released to water will mix, while the
majority of it will float on the surface.

3
Sources of Benzene

Benzene is formed from both natural
processes and human activities.
 Natural sources include crude oil, gasoline,
cigarette smoke, volcano emissions, and
forest fires.
 Benzene is used to make plastics, resins,
nylons, synthetic fibers, rubbers, dyes,
detergents, drugs, and pesticides.
4
Exposure Limits

OSHA regulates exposure to benzene (29 CFR 1910.1028)
 PEL: permissible exposure level
 STEL: short-term exposure level
 Action level: concentration at which steps must be taken to reduce
exposures and protect employee health

Other limit values:
 ACGIH TLV®: Threshold limit value; usually more stringent than
OSHA
Concentration
OSHA PEL (averaged over 8 hours)
1 ppm
OSHA STEL (max of 15 min/day)
5 ppm
OSHA Action Level (averaged over 8 hours)
0.5 ppm
ACGIH TLV® (averaged over 8 hours)
0.5 ppm
ACGIH STEL (max of 15 min/day)
2.5 ppm
5
Exposure Limits (cont.)

Most individuals can begin to smell benzene in air
at a concentration of 1.5 to 4.7 ppm (=odor
threshold).
 The 8-hour OSHA PEL is 1 ppm.
 The 15-min OSHA STEL is 5 ppm.


Thus, if you can smell benzene, you would likely
exceed the PEL if you worked for 2-8 hours with
benzene, and exceed the 15-min STEL.
The odor threshold is useful for estimating
potential acute exposures (large amounts of
benzene over a short period of time), but is not
useful for estimating potential chronic exposures
(small amounts of benzene over long periods of
time).
6
Routes of Exposure and Health
Effects

Inhalation—acute exposure (large concentrations
of benzene over short periods of time):









Breathlessness
Irritability
Euphoria or giddiness
Irritation of eyes, nose and respiratory tract
Headache
Dizziness
Nauseated
Feeling of intoxication
Severe exposures can lead to convulsions and loss of
consciousness or death
7
Routes of Exposure and Health
Effects (cont.)

Inhalation—chronic exposure (small concentrations
of benzene over long periods of time):
 Blood disorders including anemia and leukemia

Skin
 Irritation, dermatitis, defatting of the skin with prolonged or
repeated contact
 Skin contact with liquid or vapor is a significant route for
internal exposure via absorption.

Eyes
 Moderate to severe irritant
8
Routes of Exposure and Health
Effects (cont.)

Ingestion
 Similar to inhalation effects
 If aspirated into lungs during vomiting, benzene may
cause chemical pneumonia, which may be fatal.

Pre-existing medical conditions can be
aggravated
 Open wounds, skin disorders, dermatitis
 Chronic respiratory disease, liver or kidney
dysfunction, blood, cardiovascular and central
nervous system disorders
9
How to Protect Yourself





Keep benzene away from sparks, flames,
and excessive temperatures.
Use non-sparking tools when opening or
closing benzene containers.
Always use benzene in a properly
functioning fume hood and always work at
least 6” inside the sash.
Do not work alone.
Wash thoroughly after handling.
10
How to Protect Yourself (cont.)

Wear personal protective equipment (PPE):
 Gloves: Best Viton® (28 mil) or Ansell PVA
○ Do NOT use nitrile or latex!
 Chemically-resistant lab coat: Tyvek-Saranex 23,




Tychem, or Barricade
Splash goggles
Splash goggles and face shield if using large amounts
(> 1L)
Rubber boots or closed toed shoes (no sandals or
mesh type tennis shoes)
Respirator is to be used only if work is conducted
outside a fume hood.
○ Medical evaluation, fit testing and training is required.
Contact EHSRM at 474-6771 for assistance.
11
Storage
Store in a cool, well-ventilated area.
 Keep container tightly closed as vapors
may form explosive mixtures in air.
 Keep away from sources of ignition
including electrostatic charges.
 Do not store with acids, bases,
halogens, strong oxidizing agents, or
metallic salts.

12
Spills and Exposures

Spills not involving contact with a person
(small spill, e.g. a few ml, in fume hood)
○ Turn off or remove ignition sources.
○ Continue to wear proper PPE.
○ Use vermiculite or other non-combustible
absorbent material to soak up spill.
○ Place spill residue in fire-proof or metal
container and call EHSRM at 474-5617 or 4745413 to arrange for pickup of the cleanup
materials.
13
Spills and Exposures
REMEMBER If you do not feel comfortable cleaning
up a small spill, call EHSRM for help (never put
yourself at risk!)
474-5617 or 474-5413
Dispatch (after hours) 474-7721
NEVER put benzene down the drain!
Any release of benzene to the sewer must be
immediately reported to EHSRM at 474-5617 so
that they can notify the water treatment plant
and/or ADEC.
14
Spills and Exposures

Spills not involving contact with a person
(cont.)
 Small spill outside fume hood, or a large spill:
○ Turn off all ignition sources.
○ Alert others in the area to evacuate the lab.
○ Contain the spill with non-combustible absorbent
material only if it is safe to do so.
○ Leave the area and close the door.
○ Call EHSRM Division of Hazardous Materials at
474-5617 or 474-5413 during business hours, or
Dispatch at 474-7721 after business hours.
15
Spills and Exposures

In the event of a power outage and/or loss of
fume hood function:
 Close and properly store all containers containing
benzene.
 If unable to close containers:
○ Turn off all ignition sources
○ Close hood sash
○ Alert others in the area to evacuate the lab
○ Leave the area and close the door
 Wait 15 minutes after power is restored before re-
entering lab to assure adequate ventilation.
16
Spills and Exposures

Spills involving exposure to a person
 If exposure victim requires assistance, responder should don
proper PPE first.
 Skin contact: Immediately wash with soap and water and remove
contaminated clothing (including shoes). Get medical attention if
irritation persists.
 Eye contact: promptly wash with copious amounts of water for 15
minutes (lifting upper and lower eyelids occasionally) and seek
medical attention.
 Inhalation: Move person to fresh air and seek medical attention.
Give artificial respiration if not breathing.
 Ingestion: Do not induce vomiting. Do not give liquids. Get medical
attention immediately.
17
Spills and Exposures

Immediately notify your supervisor and
EHSRM of any exposures, regardless of how
small and insignificant they may seem (4746771 or 474-5413).

If the victim is admitted to the hospital, you
are required to notify EHSRM at 474-5413
within 8 hours so that we can notify OSHA.
Failure to do so can result in a fine for UAF
and/or your department.
18
Monitoring
 Air
sampling may be conducted in order to
determine the exposure levels experienced by
workers.
 If the initial monitoring indicates that the air
concentration to be below the action level (0.5
ppm) the monitoring can be discontinued except
when there:
 Is a change in the production, process, control
equipment, personnel, or work practices
 Has been a spill, leak, rupture, or other breakdown
that may result in exposure
19
Monitoring (cont.)


If the air concentration is at or above the
action level (0.5 ppm), but at or below the
PEL (1 ppm), monitoring must be done at
least once per year.
If the air concentration is at or above the
PEL (1 ppm), monitoring must be done
every six months.
20
Monitoring (cont.)
 Employees
must be notified in writing of
monitoring results within 15 working days.
 If
the PELs are exceeded, the written notification
shall contain the corrective action being taken to
reduce the exposure to or below the PEL.
 Contact
the UAF Industrial Hygienist at 4746771 or 474-5197 for assistance with air
monitoring.
21
Medical Surveillance

Medical surveillance is required for:
 exposures to benzene at or above the action level
30 or more days per year.
 exposures to benzene at or above the PEL 10 or
more days per year.
 exposures to more than 10 ppm of benzene for 30
or more days in a year.

Arrangements for medical surveillance are
made through EHSRM (474-6771), and are
provided at no cost to the employee or
department.
22
Regulated Areas
A regulated area will be established wherever
the airborne concentration of benzene
exceeds or can reasonably be expected to
exceed the PEL (1 ppm) or the STEL (5 ppm).
 Access to regulated areas will be posted and
limited to authorized persons.

23
Waste Disposal




Place benzene waste in sealed, intact containers,
clearly labeled with:
Benzene Waste
Danger:
Cancer Hazard
Flammable
Keep the container sealed at all times when not
adding wastes to it.
Properly store the waste container (see slide 12).
Contact EHSRM Hazmat Division for pickup and/or
assistance at 474-5617.
24
For More Information:

http://www.osha.gov/pls/oshaweb/owadisp.sh
ow_document?p_id=10042&p_table=STAND
ARDS

http://www.cdc.gov/NIOSH/ershdb/Emergenc
yResponseCard_29750032.html

http://www.bt.cdc.gov/agent/benzene/basics/f
acts.asp

http://www.sunocochem.com/HES/BenzeneB
ookFINAL.pdf
25