Archive Notice - OSHA Archive

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at

February 26, 1996

Mr. David S. Abrams
Clayton Environmental Consultants
7800 Metro Parkway
Suite 100
Minneapolis, Minnesota 55425

Dear Mr. Abrams:

This is in response to your letter to the Occupational Safety and Health Administration (OSHA) requesting an interpretation on respirator use under the Interim Final Rule for Lead in Construction, 29 CFR 1926.62. Your request for an interpretation pertains to the use of a tight fitting, air purifying, negative pressure half mask respirator, equipped with HEPA filters in conjunction with a Type CE, abrasive blasting hood, and whether the assigned protection factors (APF) for these respirators can be combined for a higher APF. Please accept our apology for the long delay in our response.

The provision at 29 CFR 1926.62(f)(2)(iii) states ..."The employer shall select respirators from among those approved for protection against lead dust, fume, and mist by the Mine Safety and Health Administration and the National Institute for Occupational Safety and Health (NIOSH) under the provisions of 30 CFR part 11." Under the provisions of 30 CFR part 11, Type CE abrasive-blast respirators are the only respirators approved for use in abrasive-blasting operations. The models of Type CE abrasive-blast respirators certified under 30 CFR part 11 are: (1) a continuous-flow respirator containing a loose-fitting hood with a protection factor of 25; (2) a continuous-flow respirator containing a tight-fitting facepiece with a protection factor of 50; (3) a positive pressure, supplied-air respirator containing a half-facepiece with hood with a protection factor of 1000; and (4) a positive pressure, pressure-demand respirator containing a tight-fitting full-facepiece with a protection factor of 2000.

The combination of a tight-fitting, air purifying, negative pressure, half-faepiece respirator with the Type CE, abrasive-blast respirator was never approved by NIOSH under 30 CFR 11. OSHA requires NIOSH certified respirators per 29 CFR 1926.62(f)(2)(iii). Use of non-certified respirators is a violation.

APFs have been determined through rigorous test procedures implemented under 30 CFR 11 by NIOSH. Assignment of protection factors is not an arbitrary procedure, such as multiplying the APF of two respirators used in combination, to achieve a higher APF. If you wish to have the unit of a tight-fitting, air purifying, negative pressure, half-facepiece respirator used in conjunction with a Type CE, loose-fitting, abrasive-blast respirator considered for certification by NIOSH as an abrasive-blast respirator, then you must apply for approval and submit all respirator components as required by NIOSH. NIOSH certifies respirators under 42 CFR 84, now. Please bear in mind that NIOSH issued new respirator certification regulations at 42 CFR 84 in July, 1995.

On August 30, 1995, OSHA implemented an interim enforcement policy change for respiratory protection required for abrasive blasting under 29 CFR 1926.62, the Interim Final Rule for Lead in Construction. This interim enforcement policy change accepts an APF to 1000 for the E.D. Bullard Company's Type CE, abrasive-blast respirators, Models 77 and 88 only when they are used under specific conditions. This change only applies to 29 CFR 1926.62 and it is effective until a final determination by OSHA is made of the proper protection factor to be assigned this class of respirators. A copy of this enforcement policy change is enclosed for your information.

Thank you for seeking clarification on this issue and for your interest in safety and health in the workplace.


Ruth McCully, Director
Office of Health Compliance Assistance


October 2, 1995

Ms. Ruth McCully
Office of Health Compliance
200 Constitution Avenue, NW
Room N3469
Washington, DC 20210

Ref: Respiratory Protection for Lead In Construction, A Request for a Letter of Interpretation

Dear Ruth:

By way of this letter, I am requesting a Letter of Interpretation regarding the use of respiratory protection and the Lead In Construction Standard, 29 CFR 1926.62. The practice for which I am requesting the Letter of Interpretation is that of using a tight fitting, air purifying, negative pressure half mask respirator, equipped with HEPA filters in conjunction with a Type CE hood.

With the assignment of a protection factor of 25 to the Type CE hoods which have historically been used in abrasive blasting operations, it has become difficult to identify a respiratory protection strategy which will provide the needed protection and receive acceptance among the painting industry. 1926.62 specifies respirators which provide protection factors of greater than 25. One would expect that regardless of the type of face piece, a painter will wear a hood when shot blasting. The hood will likely have an air supply for comfort reasons even if a tight fitting respirator is used. With one line for the hood and another for the respirator, the burden of equipment is increased for the user and the burden of required CFM of Grade D air is increased for the contractor. Should a tight fitting, air purifying, full face piece respirator be used, the field of view will likely be reduced.

Keeping in mind that there is no ideal solution, it would seem that the combination of a negative pressure, air purifying, half mask respirator fitted with HEPA cartridges worn inside of a Type CE hood (offering a combined protection factor of 250 (25 for the CE hood followed by 10 for the half mask respirator) provides a practical solution. A basic assumption in the use of this combination of respirators is that a complete respirator program is in place and that all appropriate training and fit testing has been completed.

Many shot blasters find that they are far more comfortable when the climb down off of scaffolding without the encumbrance of their hood, cape and air lines. The presence of a tight fitting respirator underneath the blasting cape will minimize the potential for exposure to lead when this practice occurs.

In summary, the combination of a tight fitting, negative pressure, air purifying respirator and a Type CE hood can offer good protection from lead dust during abrasive blasting operations.

I look forward to hearing from you.


David S. Abrams, CIH