April 18, 1996

Ms. Jeni Leberknight
Rapley Engineering Services, Inc.
900 East Nichols Avenue, Suite 250
Enqlewood, Colorado 80112

Dear Ms. Leberknight:

Thank you for your letter of March 11, requesting an interpretation of the use of the Bullard "Free Air" Pump.

This is to confirm, per your phone conversation with Doug Ray of my staff, that the issue raised by our field offices concerning the portability of the unit was not addressed in our memorandum dated January 25, 1985, to our Regional Administrators. The portability of the unit should not have any bearing on safety and health. Therefore, permanently installing the units in a facility should not create a safety or health hazard. Also please bear in mind that the four compliance requirements for the use of the Bullard "Free Air" Pump, as addressed in the memorandum of January 25, an attachment to your letter, are still in effect.

Any additional questions regarding this matter can be addressed by Doug Ray at (202) 219-8036.

Sincerely,

Ruth McCully, Director
Office of Health Compliance

March 11, 1996

Mr. John Miles
OSHA
Office of Health Compliance
200 Constitution Avenue NW
Room N3468
Washington DC 20210

Dear Mr. Miles,

We are requesting a clarification of OSHA's allowable use of the Bullard "Free-Air Pump". The issue surrounding the use of Bullard BReathing air systems has been previously detailed in memorandums for the Regional Administrators through you (Reference attached Memo's: "Health Hazard Information Bulletin Concerning Portable BReathing Air Compressors", 25 January 1985, and "Update of the Health Information Bulletin Concerning Portable BReathing Air Compressors", 2 April 1985).

As we understand the situation, you have provided exemptions of OSHA's 29 CFR 1910.134(d)(2)(ii) "Respiratory Protection" for the Bullard "Free-Air" Pump-since these devices have no air receiver to enable the respirator wearer to escape from a contaminated atmosphere in the event of a compressor failure nor do they have an alarm to indicate compressor failure or overheating, or a high temperature alarm (see prescribed citation below)

"OSHA's 29 CFR 1910.134(d)(2)(ii) The compressor for supplying air shall be equipped with necessary safety and standby devices. A BReathing air-type compressor shall be used. Compressors shall be constructed and situated so as to avoid entry of contaminated air into the system and suitable in-line air purifying sorbent beds and filters installed to further assure BReathing air quality. A receiver of sufficient capacity to enable the respirator wearer to escape from a contaminated atmosphere in event of compressor failure, and alarms to indicate compressor failure and overheating shall be installed in the system. If an oil-luBRicated compressor is used, it shall have a high-temperature or carbon monoxide alarm, or both. If only a high-temperature alarm is used, the air from the compressor shall be frequently tested for carbon monoxide to insure that it meets the specifications in paragraph (d)(1) of this section."

In addition, you stated if the use of these supplied air respirators (SARs) are limited to non-IDLH (not immediately dangerous to life or health) conditions, the requirements for an air receiver and a compressor failure alarm may not be necessary provided the escape distance is less than 300 feet. Since these compressors are not oil-luBRicated, a high temperature alarm to indicate overheating or the presence of high levels of carbon monoxide may not be required.

Your first memo indicated the essential argument for this exemption was that if a receiver were installed in this type of compressor, the unit would lose its portability. Therefore, our understanding is that if the units are hard piped and permanently installed within a facility or plant intended for normal/routine use without a receiver, the intent of your exemption does not apply and OSHA would consider this inconsistent (non-compliant) with your current regulations and guidelines. Would you please clarify if our interpretation is correct? Specifically, we are in the process of determining whether an installation consisting of four Bullard pumps manifolded together with copper tubing and used in routine operations needs to be changed to comply with OSHA regulations.

Please do not hesitate to leave me a message at (303) 792-2211 if you have any questions or comments regarding this OSHA Memorandum clarification request.

Thank you,

Jeni Leberknight
Rapley Engineering
Process Engineer
9000 East Nichols Ave, Suite 250
Englewood, CO 80112

January 25, 1985

MEMORANDUM FOR:  REGIONAL ADMINISTRATORS

ATTN:            ARAs for Technical Support

THRU:            JOHN B. MILES
                Director
                Directorate of Field Operations

FROM:            EDWARD J. BAIER
                Director
                Directorate of Technical Support

SUBJECT:         Health Hazard Information Bulletin
                Concerning Portable BReathing Air Compressors

Recently, it has come to our attention that two respirator manufacturers are marketing approved supplied air respirators (SAR) equipped with portable air compressor as a source of air supply. These SARs are the Bullard "Free-air Air Pump" and the Willson "Ambient Air BReathing Apparatus" (information attached). They are used in many workplaces which do not have a compressed air supply.

Some questions were raised by our field offices concerning whether these air compressors would meet the requirements prescribed in the standard on respirator protection, 29 CFR 1910.134[(i)(5-7)]. Since these devices have no air receiver to enable the respirator wearer to escape form a contaminated atmosphere in the event of a compressor failure, nor do they have an alarm to indicate compressor failure or overheating, or a high temperature alarm, they do not meet the requirements prescribed in the standard. If a receiver were installed in this type of compressor, the unit would lose its portability.

Under our current policy, supplied air respirators are not to be used in an atmosphere which is immediately dangerous to life of health (IDLH) unless it is equipped with a self-contained air supply for escape. If the use of these SARs is limited to non-IDLH conditions, the requirements for an air receiver and a compressor failure alarm may not be necessary, provided the wearer carries an escape respirator in the event of a compressor failure. Since these compressors are not oil luBRicated, a high temperature alarm to indicate overheating or the presence of high levels of carbon monoxide may not be required.

In view of the fact that these SARs are operated in the positive-pressure mode, the portable supplied air respirator system could provide a high level of protection for employees engaged in operations such as asbestos removal or spray painting with isocyanide-containing paints. Use of these units should be encouraged despite the fact that they do not meet the requirements described above.

The Bullard "Free-air Air Pump" and the Willson "Ambient BReathing Apparatus" are acceptable provided the following requirements are met:

1. These devices are not to be used in an atmosphere which is immediately dangerous to life or health.

2. Air used for this equipment must be drawn from an uncontaminated air source. Suitable filters and sorbents shall be installed and maintained when the need arises.

3. The air delivered by the compressor at the BReathing zone of the SAR wearer must meet the requirements of Grade D BReathing air as prescribed in 29 CFR 1910.134[(i)(1)(ii)].

4. The respirator wearer must carry an additional air-purifying respirator (with appropriate sorbent or filter) for quick donning and escape from the contaminated atmosphere in the event of a compressor or SAR failure. Quantitative or qualitative fit testing shall be performed to select the facepiece which would provide adequate protection. The employee must be trained for quick donning of the escape respirator.

ATTACHMENT

April 2, 1985

MEMORANDUM FOR:  REGIONAL ADMINISTRATORS

ATTN:            ARAs FOR TECHNICAL SUPPORT

THRU:            JOHN B. MILES
                Director
                Director of Field Operations

FROM:            EDWARD J BAIER
                Director
                Directorate of Technical Support

SUBJECT:         Update of the Health Information Bulletin
                Concerning Portable BReathing Air Compressors

My memorandum dated January 25, 1985, concerned the use of portable air compressors to supply BReathing air to certain continuous flow supplied air respirators (SAR). It was indicated that the respirator wearer must carry an additional air-purifying respirator (with appropriate sorbent or filter) for quick donning and escape from the contaminated atmosphere in the event of a compressor or SAR failure. We have received numerous requests for clarification of this issue.

The major question concerns the situation in which the combination of a SAR and a portable air compressor is used in an atmosphere which is not immediately dangerous to life or health (IDLH). Why should a backup respirator be required? Usually an IDLH concentration is established for a gas or vapor. However, very few IDLH concentrations have been established for particulates.

Since the continuous flow supplied air respirators are permissible at levels up to 1,000 times the OSHA permissible exposure limit (PEL) for contaminants without IDLH values, the wearer may be overexposed in the event of the SAR failure if the time to escape to an uncontaminated area is prolonged. However, it should be noted that these portable air compressors must draw air from an uncontaminated source, with a limit on length of airline of 300 feet, as prescribed in [42 CFR Part 84]. In this case the wearer could escape to an uncontaminated area in a very short time.

In view of the above, a backup respirator would not be required for a combination of the SAR and the portable air compressor provided the device is not used in IDLH concentrations and the escape distance is less than 300 feet.