Benzene scope and application

The benzene standard applies to all occupational exposures to benzene (CAS No. 71-43-2) except for the specific exclusions listed in the standard. See 1910.1028(a)(1).

• Employers must treat any workplace benzene exposure as covered unless an exclusion in 1910.1028(a)(2) or (a)(3) clearly applies.
• "Benzene" is defined in 1910.1028(b) and includes benzene in liquids and released vapors.

Yes — routine retail dispensing of gasoline that is dispensed outdoors or indoors for 4 hours or less per day is generally excluded, but gasoline dispensing done indoors for more than 4 hours per day is covered by the benzene standard. See 1910.1028(a)(2)(i).

• If employees dispense gasoline indoors for more than 4 hours in a day, the employer must comply with applicable benzene requirements (monitoring, controls, etc.).
• Remember that other exclusions and requirements may still apply depending on the workplace.

Loading and unloading operations at bulk wholesale storage facilities are excluded only if vapor control systems are used for all loading and unloading operations; otherwise those operations are covered except for certain incorporated provisions. See 1910.1028(a)(2)(ii).

• Even where excluded, the Hazard Communication requirements at 1910.1200 and the emergency provisions of 1910.1028(g) and 1910.1028(i)(4) still apply as noted in the standard.

Sealed intact containers or transportation pipelines that keep benzene vapors contained are excluded, and containers/pipelines carrying mixtures with less than 0.1% benzene are also excluded; however, the Hazard Communication and certain emergency provisions still apply. See 1910.1028(a)(2)(iii) and 1910.1028(a)(2)(iv).

• If your work requires opening sealed containers or otherwise releasing benzene vapors, the exclusion does not apply and the full standard will likely apply.
• Even where excluded, employers must still comply with the incorporated parts of 1910.1200 and emergency provisions as noted.

Exclusions for work operations using benzene-containing liquids get stricter over time: before Sept 12, 1988 the threshold was 0.5%; from Sept 12, 1988 to Sept 12, 1989 it was 0.3%; and after Sept 12, 1989 it is 0.1% benzene by volume. See 1910.1028(a)(2)(v).

• If the only exposure is from liquids with benzene at or below those thresholds for the given dates, the operation may be excluded.
• Note the exception that tire building machine operators using solvents with more than 0.1% benzene are covered by 1910.1028(i).

Oil and gas drilling, production and servicing operations and coke oven batteries are expressly excluded from coverage under the benzene standard. See 1910.1028(a)(2)(vi) and 1910.1028(a)(2)(vii).

• Employers in these excluded operations should consult any industry-specific standards or State-plan requirements that may apply.

Cleaning and repair of barges and tankers that have contained benzene are excluded from certain monitoring and compliance paragraphs, but employers must use engineering and work-practice controls to keep exposures below 10 ppm unless infeasible. See 1910.1028(a)(3).

• The exclusions specifically remove these tasks from paragraph (f) methods of compliance, paragraph (e)(1) exposure monitoring-general, and paragraph (e)(6) accuracy of monitoring.
• Despite those exclusions, employers still must apply engineering/work-practice controls to limit exposures to below 10 ppm unless they can demonstrate infeasibility.

Benzene is defined as liquefied or gaseous benzene (C6H6), including benzene contained in liquid mixtures and benzene vapors released by these liquids; trace unreacted benzene in solids is not included. See the definition in 1910.1028(b).

• This means employers must consider both liquid benzene and vapors from benzene-containing liquids when assessing exposures.
• The standard excludes trace benzene in solid materials from that definition.

The action level for benzene is 0.5 ppm as an 8-hour time-weighted average. See the definition for Action level in 1910.1028(b).

• Reaching or exceeding the action level triggers additional monitoring and potentially medical surveillance and other requirements under the standard (see monitoring provisions in 1910.1028(e)).

The permissible exposure limits are a time-weighted average (TWA) of 1 ppm over 8 hours and a short-term exposure limit (STEL) of 5 ppm averaged over any 15-minute period. See 1910.1028(c)(1) and 1910.1028(c)(2).

• Employers must ensure no employee is exposed above these limits, using engineering controls, work practices, or, where necessary, respirators and other protections.

An employer must establish a regulated area wherever benzene airborne concentrations exceed or can reasonably be expected to exceed either the 8-hour TWA of 1 ppm or the 15-minute STEL of 5 ppm. See 1910.1028(d)(1).

• Access to these regulated areas must be limited to authorized persons per 1910.1028(d)(2).
• Regulated areas should be sized or located to minimize the number of employees exposed, per 1910.1028(d)(3).

Employers must use breathing zone air samples that are representative of each employee's average exposure to benzene. See 1910.1028(e)(1)(i).

• Representative 8-hour TWA exposures should be determined using one sample or multiple samples representing full-shift exposure for each job classification in each work area per 1910.1028(e)(1)(ii).
• For STEL compliance, 15-minute breathing zone samples are required where there's reason to believe short-term exposures may be high (see 1910.1028(e)(1)(iii)).

Initial monitoring must be completed within 30 days of the introduction of benzene into the workplace (or by 60 days after the standard's effective date where applicable). See 1910.1028(e)(2)(i) and 1910.1028(e)(2)(ii).

• If valid monitoring within one year before the effective date meets requirements, an employer may rely on that earlier monitoring (see 1910.1028(e)(3)).

If initial monitoring shows exposures at or above the action level (0.5 ppm) but at or below the TWA (1 ppm), monitor at least annually; if above the TWA, monitor at least every six months. See 1910.1028(e)(3)(i) and 1910.1028(e)(3)(ii).

• The employer may reduce monitoring to annually for an employee if two consecutive measurements (≥7 days apart) show exposures decreased to the TWA or below but are at/above the action level per 1910.1028(e)(3)(iii).
• STEL monitoring must be repeated as necessary to evaluate short-term exposures 1910.1028(e)(3)(iv).

Employers may discontinue monitoring for an employee if initial or periodic monitoring shows exposures below the action level (except as required by 1910.1028(e)(5)). However, employers must institute or add monitoring when production, processes, controls, personnel, or work practices change or when there is reason to suspect new or additional exposures. See 1910.1028(e)(4)(i), 1910.1028(e)(4)(ii), and 1910.1028(e)(5)(i).

• After spills, leaks, or breakdowns that may have exposed employees, employers must monitor after cleanup or repair to ensure exposures returned to pre-incident levels per 1910.1028(e)(5)(ii).

Monitoring must be accurate to a 95% confidence level within ±25% for airborne benzene concentrations, and employers must notify affected employees of monitoring results within 15 working days after receipt of results. See 1910.1028(e)(6) and 1910.1028(e)(7)(i).

• If PELs are exceeded, the written notification must state the corrective action being taken or refer to a document that does so per 1910.1028(e)(7)(ii).
• Notification can be individual written notice or posting in an accessible location.

Yes — employers must institute engineering controls and work practices to reduce and maintain benzene exposure at or below the PELs unless they can establish that such controls are not feasible or other limited exceptions apply. See 1910.1028(f)(1).

• If engineering and work-practice controls cannot fully reduce exposures below the PELs, the employer must provide respirators and other protective measures as required by the standard.

Employers should perform 15-minute STEL monitoring where there is reason to believe short-term exposures are high — for example, when tanks are opened, filled, unloaded, gauged, process equipment is opened, or benzene is used as an uncontrolled solvent or cleaning agent. See 1910.1028(e)(1)(iii).

• Employers may use objective data or brief-period measuring devices to decide where STEL monitoring is needed.
• Monitor at operations with plausible short-term high exposures to capture peak risks.

Yes — except for the initial monitoring required under 1910.1028(e)(2), an employer can limit representative exposure determinations to the shift that consistently has the highest exposures, if the employer documents that that shift will consistently have higher employee exposures. See 1910.1028(e)(1)(iv).

• This reduces monitoring burden where exposure patterns are stable and well documented, but employers must maintain the documentation supporting the decision.

"Employee exposure" is defined as the airborne benzene concentration to which an employee would be exposed if the employee were not using respiratory protective equipment. See the definition in 1910.1028(b).

• This means monitoring and compliance determinations are based on exposures without respirators; respirators are treated as a supplemental control when engineering controls cannot keep exposures at or below the PELs.

Access to regulated areas must be limited to authorized persons only — defined as those specifically authorized by the employer whose duties require entry, designated employee representatives observing monitoring, or others authorized by law or regulation. See 1910.1028(d)(2) and the definition of "authorized person" in 1910.1028(b).

• Employers should document who is authorized and communicate protective measures required for entry (PPE, training, etc.).

Yes — when an exclusion in 1910.1028(a)(2) applies (for example sealed containers or vapor-controlled loading), the Hazard Communication requirements in 1910.1200 and certain emergency provisions of the benzene standard still apply as specified in the exclusion text. See 1910.1028(a)(2)(ii) and 1910.1028(a)(2)(iii).

• Employers cannot assume a full exemption from benzene-related obligations just because a narrow exclusion applies; they must still meet Hazard Communication and emergency duties where required.

Employers must provide respiratory protection whenever feasible engineering and work-practice controls cannot reduce employee exposures to or below the PELs. Under 1910.1028(f)(1)(ii), employers must implement all feasible engineering and work-practice controls and supplement them with respirators to reduce exposure to the lowest levels achievable when those controls alone are not sufficient.

If benzene is used less than 30 days per year, the employer may use engineering controls, work-practice controls, or respiratory protection (or any combination) to meet the PELs, but must use engineering and work-practice controls, if feasible, to reduce exposure to at or below 10 ppm as an 8-hour TWA. See 1910.1028(f)(1)(iii).

The employer must establish a written compliance program whenever any employee exposures exceed the PEL. 1910.1028(f)(2)(i) requires a written program to reduce exposure to or below the PEL primarily through engineering and work-practice controls.

The written compliance program must include a schedule for developing and implementing the engineering and work-practice controls. 1910.1028(f)(2)(ii) requires employers to document the timeline for when controls will be developed and put into place.

The written compliance program must be furnished upon request to the Assistant Secretary, the Director, affected employees, and designated employee representatives. See 1910.1028(f)(2)(iii).

Respirators are required during periods necessary to install/implement engineering or work-practice controls, for operations where controls cannot feasibly achieve the TWA or STEL, for operations where controls are not yet sufficient, and during emergencies. See the list in 1910.1028(g)(1) and its subparts (i)–(iv).

Employers must implement a respiratory protection program that meets the provisions of 1910.134(b)–(d) and (f)–(m) (with specified exceptions). 1910.1028(g)(2)(i) requires a full program covering each employee required to use a respirator under the benzene standard.

For air‑purifying respirators, employers must replace the element at the end of its service life or at the beginning of each shift in which it is used, whichever comes first. If NIOSH approves an air‑purifying element with an end‑of‑service‑life indicator for benzene, it may be used until the indicator shows no useful life. See 1910.1028(g)(2)(ii)–(iii).

Employers must select and provide respirators specified in 29 CFR 1910.134(d)(3)(i)(A), supply an organic vapor gas mask or any self‑contained breathing apparatus with a full facepiece for escape, and use organic vapor cartridges/canisters with powered and non‑powered air‑purifying respirators (or a chin‑style canister for full facepiece gas masks). See 1910.1028(g)(3)(i)(A)–(C).

Canisters used with non‑powered air‑purifying respirators must have a minimum service life of four hours when tested at 150 ppm benzene, 64 LPM flow, 25 °C, and 85% relative humidity. See 1910.1028(g)(3)(i)(D).

Any employee who cannot use a negative‑pressure respirator must be allowed to use a respirator with less breathing resistance, such as a powered air‑purifying respirator or a supplied‑air respirator. See 1910.1028(g)(3)(ii).

The employer must provide protective clothing and equipment at no cost to the employee and must ensure its use where appropriate to prevent eye contact and limit dermal exposure to liquid benzene. See 1910.1028(h) and the eye‑face protection requirement in 1910.133.

Medical surveillance must be made available to employees exposed at or above the action level 30 or more days per year; to those exposed at or above the PELs 10 or more days per year; to employees who had prior exposure above 10 ppm for 30+ days before the standard when employed by their current employer; and to tire building machine operators using solvents with >0.1% benzene. See 1910.1028(i)(1)(i).

The initial exam must include a detailed occupational history (past benzene and hematologic toxin exposure, family history of blood dyscrasias, medical history items listed), a complete physical exam, and laboratory tests including a complete blood count with differential, thrombocyte count, hematocrit, hemoglobin, erythrocyte count, and erythrocyte indices; results must be reviewed by the physician. See 1910.1028(i)(2)(i)–(i)(2)(i)(C).

No initial exam is required if adequate records show the employee was examined in accordance with the standard within the twelve months prior to the effective date of the standard. See 1910.1028(i)(2)(ii).

Employers must provide an annual medical examination following the previous examination for employees covered under [1910.1028(i)(1)(i)]. See 1910.1028(i)(3)(i).

For persons required to use respirators for at least 30 days per year, a pulmonary function test must be performed every three years; a specific cardiopulmonary evaluation must also be made at that time. See 1910.1028(i)(3)(iii).

After an emergency benzene exposure, the employer must obtain a urine sample at the end of the shift and have a urinary phenol test performed within 72 hours (corrected to a specific gravity of 1.024); if result is ≥75 mg phenol/L, the employer must provide monthly complete blood counts for three months. See 1910.1028(i)(4)(i)–(iii).

If CBC results show hemoglobin/hematocrit below normal limits (outside 95% C.I.) or persistent downward trends, platelets drop >20% or outside 95% C.I., or leukocyte count <4,000/mm3 or abnormal differential, the CBC shall be repeated within 2 weeks and persistent abnormalities require referral to a hematologist or internist; the employer must provide the specialist with required medical and exposure records. See 1910.1028(i)(5)(i)–(iv).

The written compliance program must be furnished upon request to the Assistant Secretary, the Director, affected employees and designated employee representatives, and medical records must be maintained and provided as required by 1910.1028(k)(2)(ii) and 1910.1028(f)(2)(iii). Employers must comply with those provisions when records or programs are requested.

You must give the examining physician the items listed in 1910.1028(i)(6). Specifically, provide:

• A copy of the benzene regulation and its appendices as required by 1910.1028(i)(6)(i).
• A clear description of the employee’s duties that relate to benzene exposure as required by 1910.1028(i)(6)(ii).
• The employee’s actual or representative exposure level(s) to benzene per 1910.1028(i)(6)(iii).
• A description of any personal protective equipment used or to be used (including respirators) as required by 1910.1028(i)(6)(iv).
• Any relevant information from prior employment-related medical exams that the physician would not otherwise have, per 1910.1028(i)(6)(v).

Providing this information helps the physician make appropriate medical judgments about fitness for work and necessary follow-up under the benzene medical surveillance requirements in 1910.1028(i).

The physician's written opinion must include only the specific items listed in 1910.1028(i)(7). It must state:

• The occupationally pertinent results of the examination and tests per 1910.1028(i)(7)(i)(A).
• Whether the physician finds any medical condition that would place the employee at greater-than-normal risk of material impairment from benzene exposure as required by 1910.1028(i)(7)(i)(B).
• Any recommended limitations on the employee’s benzene exposure or use of protective clothing/equipment and respirators per 1910.1028(i)(7)(i)(C).
• A statement that the physician informed the employee of the exam results and any benzene-related conditions requiring further explanation or treatment as required by 1910.1028(i)(7)(i)(D).

The written opinion must not reveal unrelated specific records, findings, or diagnoses that have no bearing on the employee’s ability to work in a benzene-exposed workplace, as prohibited by 1910.1028(i)(7)(ii). The employer must give the employee a copy of the physician’s written opinion within 15 days of the exam per 1910.1028(i)(7).

If a physician refers an employee to a hematologist and removal is recommended, the employer must follow the medical removal plan and protection rules in 1910.1028(i)(8) and (i)(9). Specifically:

• The employee must be removed from areas where benzene exposures may exceed the action level until the hematologist/physician team makes a determination, per 1910.1028(i)(8)(i).
• The decision to remove or return the employee must be made in writing by the physician in consultation with the hematologist/internist, and must state probable duration of removal and requirements for future medical exams, per 1910.1028(i)(8)(ii).
• For temporarily removed employees, the employer must provide a comparable job with benzene exposure as low as possible and not above the action level; if none is available, the employer must provide medical removal protection benefits for up to 6 months, per 1910.1028(i)(8)(iv) and 1910.1028(i)(9)(i).
• A follow-up exam must be provided and within 6 months the physician (with the hematologist) must decide whether the employee returns to the usual job or is removed permanently, per 1910.1028(i)(8)(iii).
• If permanently removed based on physician recommendation, the employee must be offered transfer to another available position (or future vacancy) with exposures not above the action level and without loss of wage rate, seniority, or benefits as required by 1910.1028(i)(8)(v).

These protections are tied to the employer’s obligation to maintain wages, seniority and benefits during removal—see 1910.1028(i)(9)(ii) and 1910.1028(i)(9)(iii) for how outside compensation can reduce the employer’s benefit obligation.

Employers must post the required danger signs at entrances to regulated areas and label containers of benzene as set out in 1910.1028(j)(2). Specifically:

• Post signs at entrances to regulated areas bearing the legend exactly as required in 1910.1028(j)(2)(i) (for example: “DANGER BENZENE MAY CAUSE CANCER HIGHLY FLAMMABLE LIQUID AND VAPOR DO NOT SMOKE WEAR RESPIRATORY PROTECTION IN THIS AREA AUTHORIZED PERSONNEL ONLY”).
• Labels or other appropriate warnings must be provided for workplace containers of benzene and must comply with the Hazard Communication Standard per 1910.1028(j)(2)(iii) and 1910.1200(f).
• There is no requirement to label piping systems containing benzene under this section, but labels are required on containers inside the workplace per 1910.1028(j)(2)(iii).

Note: Older permitted sign legends were allowed before specified dates (see 1910.1028(j)(2)(ii) and (iv)). Ensure current signage and labels meet the latest legend and the Hazard Communication Standard in 1910.1200.

Employers must train employees at initial assignment to a benzene area and at least annually if exposures are above the action level, covering the HCS required topics plus benzene-specific information in 1910.1028(j)(3). Specifically:

• Give training at the time of initial assignment to an area where benzene is present and annually if exposures exceed the action level, per 1910.1028(j)(3) and (j)(3)(i).
• The training program must follow the Hazard Communication Standard training elements in 1910.1200(h)(1) and (h)(2).
• In addition to HCS topics, you must explain the contents of the benzene standard (including Appendices A and B) and where it’s available, and describe the medical surveillance program and Appendix C as required by 1910.1028(j)(3)(iii)(A) and (B).

Keep training records and make sure training is understandable to the workforce (language and literacy). See 1910.1028(j)(3) and the Hazard Communication training rules in 1910.1200(h).

Employers must keep detailed exposure monitoring records for at least 30 years and medical surveillance records for the duration of employment plus 30 years, as specified in 1910.1028(k). In detail:

• Exposure measurement records must include dates, number, duration, results of samples, description of how representative exposures were determined, sampling/analytical methods, respirator types worn (if any), and the names/job classifications/exposure levels of monitored employees, per 1910.1028(k)(1)(ii)(A)–(D).
• Maintain exposure records for at least 30 years as required by 1910.1028(k)(1)(iii).
• Medical surveillance records must include employee name, employer’s copy of the physician’s written opinions (initial, periodic, special), employee medical complaints related to benzene, a copy of the information provided to the physician per [1910.1028(i)(6)(ii)–(v)], and the employee’s medical/work history related to benzene or other hematologic toxins as required by 1910.1028(k)(2)(ii)(A)–(E).
• Maintain medical surveillance records for the duration of employment plus 30 years per 1910.1028(k)(2)(iii).

Follow the recordkeeping procedures in 29 CFR 1910.20 as referenced in the benzene standard.

Yes—affected employees or their designated representatives have the right to observe benzene exposure monitoring, and the employer must provide appropriate protective equipment if observing requires entering areas where PPE or respirators are required. Specifically:

• Employers must provide affected employees or their designated representatives an opportunity to observe exposure measuring or monitoring conducted under 1910.1028(e), as required by 1910.1028(l)(1).
• If observation requires entry into areas where protective clothing or respirators are required, the employer must provide the observer with the personal protective clothing and respirators required for employees in that area, ensure the observer uses them, and require the observer to comply with other applicable safety procedures, per 1910.1028(l)(2).

Allowing observation improves transparency; however, employers may require observers to follow site PPE and safety rules to protect health and safety.

Exposure and medical records must be made available to OSHA, affected employees (or their representatives), and others with the employee’s written consent; records must be transferred according to 1910.1020(h). Specifically:

• Make all records required by the benzene standard available on request to the Assistant Secretary and the Director for examination and copying per 1910.1028(k)(3)(i).
• Provide employee exposure monitoring records on request to employees, employee representatives, and the Assistant Secretary consistent with 29 CFR 1910.20(a)–(e) and (g)–(i) as required by 1910.1028(k)(3)(ii).
• Provide employee medical records upon request to the subject employee, anyone with the employee’s specific written consent, and the Assistant Secretary in accordance with 29 CFR 1910.20, per 1910.1028(k)(3)(iii).
• Transfer of records must comply with the requirements in 29 CFR 1910.1020(h), as required by 1910.1028(k)(4).

Maintain privacy and follow the procedures in 1910.20 and 1910.1020(h) when releasing or transferring records.