Color-change air purifiers and carbon monoxide testing

MEMORANDUM FOR: GILBERT J. SAULTER
Regional Administrator
ATTENTION: HERBERT M. KURTZ
ARA for Technical Support
THRU: JOHN B. MILES, JR.
Director Office of Field Coordination
FROM: BRUCE HILLENBRAND
Acting Director, Federal Compliance and State Programs
SUBJECT: Del-Monox Air Purifiers

This is in response to your memorandum of September 4, 1981, concerning the possible use of the color change feature of Del-Monox air purifying units to ensure that carbon monoxide concentrations stay within the OSHA air quality requirement for breathing air supplied by oil-lubricated compressors.

The legal procedures for ensuring that the carbon monoxide concentration in breathing air supplied by oil-lubricated compressors stays within the OSHA specification are contained in 29 CFR 1910.134[(i)(7)], which reads, in part, as follows:

~~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.~~

(Correction 11/24/98)

[For oil-lubricated compressors, the employer shall use a high-temperature or carbon monoxide alarm, or both, to monitor carbon monoxide levels. If only high-temperature alarms are used, the air supply shall be monitored at intervals sufficient to prevent carbon monoxide in the breathing air from exceeding 10 ppm.]

OSHA interprets this provision to entail a requirement to measure the concentration of carbon monoxide in the air. The Del-Monox air purifying units to which you refer in your memorandum do not perform this function.

An employer who wants to use the color change feature of the Del-Monox air purifying units instead of frequently testing the air, would have to apply for and obtain a permanent variance from the Office of Variance Determination in the Directorate of Technical Support.