OSHA's Benzene standard, 29 CFR 1910.1028, limits worker exposure to airborne benzene to 1 part per million (ppm) as an 8-hour time-weighted average and 5 ppm as a 15-minute short-term exposure limit (STEL). It sets an action level of 0.5 ppm and requires exposure monitoring, regulated areas, engineering controls, respiratory protection, medical surveillance, training and recordkeeping.
Benzene is a flammable liquid used in chemical manufacturing and present in crude oil, gasoline and many refinery streams. Long-term exposure can cause leukemia and other blood disorders, including aplastic anemia, and high short-term exposures can cause dizziness, unconsciousness and death.
What Is the Benzene Standard?
OSHA issued its benzene standard in 1987 at 29 CFR 1910.1028. Construction and shipyard employment have their own references to the same requirements. Benzene is also a common topic on the glossary and in process safety programs.
Who Must Comply?
The standard applies to all occupational exposures to benzene, with several exceptions, including:
- Storage, transportation, distribution, dispensing, sale or use of gasoline, motor fuels or other fuels containing benzene after final discharge from bulk wholesale storage facilities, except where fuels are dispensed for more than 4 hours a day indoors.
- Loading and unloading at bulk wholesale storage facilities that use vapor control systems for all loading and unloading.
- Work with liquid mixtures containing 0.1% benzene or less by volume.
- Oil and gas drilling, production and servicing operations.
- Natural gas processing plants processing gas with less than 0.1% benzene.
- Sealed containers and pipelines that are not opened, other than for necessary emergency response.
Refineries, petrochemical plants, chemical manufacturers, coke ovens, laboratories, tank cleaning and some tire manufacturing operations commonly fall under the standard. Exempt operations still have duties under the hazard communication standard and the general exposure limit tables.
Key Requirements
Exposure limits
- PEL: 1 ppm as an 8-hour TWA.
- STEL: 5 ppm averaged over any 15-minute period.
- Action level: 0.5 ppm as an 8-hour TWA.
Exposure monitoring
Employers must perform initial monitoring to determine each employee's exposure. If results are at or above the action level but at or below the PEL, monitoring must be repeated at least annually. If results are above the PEL, it must be repeated at least every six months. Monitoring may be reduced or stopped when results fall below the action level on two consecutive samples taken at least seven days apart. Employees must be notified of results in writing within 15 working days, with corrective actions described if the PEL is exceeded.
Regulated areas
The employer must establish regulated areas wherever airborne concentrations exceed or can reasonably be expected to exceed the PEL or STEL, limit access to authorized persons and post warning signs.
Methods of compliance
Engineering and work practice controls must be used to reduce exposures to or below the PELs, except where the employer can show they are not feasible or where exposure above the PEL occurs fewer than 30 days per year. Respirators are used where controls are not sufficient, during installation of controls and in emergencies.
Medical surveillance
Medical surveillance is required at no cost for employees who are or may be exposed at or above the action level 30 or more days a year, above the PEL 10 or more days a year, or in other listed situations. It includes a pre-placement exam with a complete blood count and periodic annual exams. Employees with certain blood abnormalities must be referred to a hematologist and may be removed from exposure with medical removal protection benefits.
Emergencies
After an emergency release, exposed employees must provide a urine sample at the end of the shift for urinary phenol testing, with additional follow-up if results exceed set limits.
Communication, training and records
Regulated areas must be posted with danger signs, and containers labeled under the HazCom standard. Training is required at initial assignment and at least annually for employees exposed at or above the action level. Exposure records are kept for at least 30 years and medical records for the duration of employment plus 30 years.
Penalties and Enforcement
OSHA inspects benzene exposures at refineries, chemical plants and other covered operations, and frequently cites missing monitoring, overdue medical exams and inadequate respiratory protection. Penalties are adjusted annually for inflation.
Common Compliance Mistakes
- Assuming the fuel distribution exemption covers all fuel handling, including indoor dispensing over 4 hours a day.
- Sampling only full-shift TWAs and missing short-term peaks during tank gauging, sampling or line breaking.
- Letting medical exams lapse for employees who meet surveillance triggers.
- Not posting regulated areas.
- Missing the 15-working-day notification deadline.
How to Comply: Step by Step
- Confirm applicability. Review processes and exemptions, and identify benzene-containing materials using safety data sheets.
- Monitor exposure. Sample full-shift and short-term exposures for representative tasks.
- Notify employees. Provide written results within 15 working days.
- Control and restrict. Install engineering controls and establish posted regulated areas.
- Protect workers. Provide respirators and PPE where needed under a written program.
- Enroll in surveillance. Track who meets medical surveillance triggers and schedule exams.
- Train and record. Train employees annually and retain exposure and medical records.
How SMS360 Helps
SMS360's Safety Data Sheets library helps teams find every benzene-containing product, and Risk Assessment documents exposure evaluations by task. Compliance Management tracks monitoring and medical exam schedules, and Training Management keeps annual benzene training records.
Frequently Asked Questions
What is the OSHA PEL for benzene?
1 ppm as an 8-hour TWA and 5 ppm as a 15-minute STEL, with an action level of 0.5 ppm.
Are gas stations covered?
Generally no. Fuel dispensing after final discharge from bulk wholesale storage is exempt, unless fuel is dispensed for more than 4 hours a day indoors.
How often must benzene exposure be monitored?
Annually if results are at or above the action level and at or below the PEL, and every six months if results are above the PEL.
What health effects does benzene cause?
Long-term exposure can cause leukemia and blood disorders such as aplastic anemia. High short-term exposure can cause dizziness, unconsciousness and death.
