PowerPoint - University of Alaska Fairbanks

Transcript PowerPoint - University of Alaska Fairbanks

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.

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 OSHA PEL (averaged over 8 hours) OSHA STEL (max of 15 min/day) OSHA Action Level (averaged over 8 hours) ACGIH TLV® (averaged over 8 hours) ACGIH STEL (max of 15 min/day) Concentration 1 ppm 5 ppm 0.5 ppm 0.5 ppm 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).

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.

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

outside a fume hood. if work is conducted ○ Medical evaluation, fit testing and training is required. Contact EHSRM at 474-6771 for assistance.

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.

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 474 5413 to arrange for pickup of the cleanup materials.

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.

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.

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.

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 (474 6771 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.

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.

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 474 6771 or 474-5197 for assistance with air monitoring.

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.

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.

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.

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