Lead paint concentration and construction exposure assessment

March 1, 1999

Mr. Hsin H. Chou
Project Manager
Panacea Environmental Services
[Recipient address omitted]

Dear Mr. Chou:

Thank you for your letter of April 22, 1998, regarding the concentration of lead in paint which triggers the lead-in-construction standard, 29 CFR 1926.62. We regret this delay in responding.

The lead-in-construction standard was intended to apply to any detectable concentration of lead in paint, as even small concentrations of lead can result in unacceptable employee exposures depending upon on the method of removal and other workplace conditions. Since these conditions can vary greatly, the lead-in-construction standard was written to require exposure monitoring or the use of historical or objective data to ensure that employee exposures do not exceed the action level. Historical data may be applied to all construction tasks involving lead. Objective data was intended to apply to all tasks other than those listed under paragraph 1926.62(d)(2) of the standard.

OSHA does not consider X-ray fluorescence (XRF) to be an acceptable method of analysis. As stated in your letter, XRF analyzers are generally considered accurate when concentrations of lead in paint exceed 1 mg/cm². For the purposes of occupational health, these levels are considered substantial and may easily present an exposure hazard. Without having conducted monitoring, or without the benefit of historical or objective data, the employer has no assurance of the employee's exposure.

Other regulatory agencies, such as Housing and Urban Development, the Environmental Protection Agency, and the Consumer Products Safety Commission (CPSC) have designated levels of lead in paint, below which they consider the paint to be non-lead containing. The missions of these agencies differ from OSHA's, and for that reason, OSHA cannot recognize these levels as safe under workplace situations.

OSHA has recognized, however, that for certain workplace conditions, application of objective data to certain tasks listed in paragraph 1926.62(d)(2)(i)(A) may be warranted (specifically, power tool cleaning with dust collection systems, manual demolition of structures, manual scraping, and manual sanding). For these applications only, we have adopted the CPSC threshold under a very limited set of conditions.

Specifically, when a paint contains trace amounts of lead (e.g., 0.06% and below, as defined by the Consumer Products Safety Commission as non-lead containing, 16 CFR 1303), the employer may determine the concentration of lead in the air (i.e., employee exposure) by multiplying the total airborne concentration of dust times the percentage of lead in the paint. For example, if the concentration of total dust is 15 mg/m³ and the concentration of lead in paint is 0.06%, the airborne lead level will be (0.06%) x (15 mg/mm³) x (1000 µg/mg) = 9 µg/m³. Consequently, the airborne concentration of dust would have to be 50 mg/m³ before the action level of 30 µg/m³ would be reached. Arithmetically, this would read, (50 mg/m³ airborne paint) x (0.06% lead) x (1000 µg/mg) = 30 µg/m³ airborne lead.

OSHA wants to stress that this does not set 0.06% as a lower threshold for the concentration of lead in paint which would exempt the employer from the requirements of the standard. The employer must still follow all requirements of the standard and conduct an exposure assessment for the tasks involving lead. Additionally, we are not stating that the Consumer Products Safety Commission level is a "safe" concentration of lead in paint, since all tasks listed under 1926.62(d)(2) frequently entail exposures above the action level, even at extremely low concentrations of lead. We are simply stating that the application of objective data may be applied to the above-specified tasks in paragraph 1926.62(d)(2)(i)(A), under the conditions stated herein. As these are less aggressive, dust-generating methods of removal, this type of objective data may reasonably be applied.

We trust that this satisfactorily answers your concerns. If we may be of further assistance, please don't hesitate to contact the [Office of Health Enforcement] on 202-693-2190.

Sincerely,

Richard E. Fairfax
Director
Directorate of Compliance Programs

[Corrected 9/24/2008]