OSHA Instruction STD 1-10.2 OCT 30, 1978

OSHA PROGRAM DIRECTIVE #100-69

TO: REGIONAL ADMINISTRATORS/OSHA

THRU: DONALD E MACKENZIE Acting Field Coordinator

SUBJECT: Drains on Air Receivers; 29 CFR 1910.169(a) (2)(i) and (b)(2)

1. Purpose

To provide guidelines for issuance of citations for violation of drain requirements for air receivers.

2. Documentation-Affected

None.

3. Background

a. An inquiry has been received regarding Occupational Safety and Health Administration (OSHA) enforcement of 29 CFR 1910.169(b)(2) which requires a bottom drain at the lowest point of every air receiver. It states, relevantly, that:

A drain pipe and valve shall be installed at the lowest point of every air receiver to provide for the removal of accumulated oil and water

b. This inquiry notes the problem of an apparent inconsistency with 29 CFR 1910.169(a)(2)(i) which requires either a bottom drain or, alternatively, a side drain; that is, a pipe extending inward from any location to within 1/4 inch of the lowest point, in accordance with the 1968 edition of the American Society of Mechanical Engineers (A.S.M.E.) Boiler and Pressure Vessel Code, Section VIII. Specifically, it requires that:

All new air receivers installed after the effective date of these regulations shall be constructed in accordance with the 1968 edition of the A.S.M.E. Boiler and Pressure Vessel Code, Section VIII.

OSHA Instruction STD 1-10.2 OCT 30, 1978

c. This problem arises only with regard to air receivers covered by Paragraph U-1 Scope, A.S.M.E. Boiler and Pressure Vessel Code, Section VIII, 1968, which excludes vessels having an internal or external operating pressure not exceeding 15 psi. and vessels having an inside diameter not exceeding 6 inches, and 29 CFR 1910.169(a)(1), which specifies the applicability of the standard.

d. This problem also arises only with regard to air receivers subject to corrosion since, apparently, 29 CFR 1910.169(b)(2) originally was intended to apply only to an air receiver subject to corrosion. See Rule 7.3 of the source standard for 29 CFR 1910.169(b)(2), ANSI B-19, 1938, Safety Code for Compressed Air Machinery. Note that the 1968 edition of the A.S.M.E. Boiler and Pressure Vessel Code, Section VIII, paragraph UG-25(e) limits the drain construction requirements to pressure vessels subject to corrosion.

4. Action

a. It is apparent that, despite the limited requirement of 29 CFR 1910.169(b)(2) regarding a "lowest point" drain, 29 CFR 1910.169(a)(2)(i) provides for an alternative to this; namely, a side drain. Thus, where side drains are present on air receivers, citations for violation of the (b)(2) requirement are not appropriate, even if the air receiver was constructed prior to April 28, 1971, since this is allowed for in 29 CFR 1910.169(a)(2)(i). (Note, however, that (b)(2) may be appropriately cited where there are violations of the other requirement that:

The drain valve on the air receiver shall be opened and the receiver completely drained frequently and at such intervals as to prevent the accumulation of excessive amounts of liquid in the receiver.)

b. A citation for violation of 29 CFR 1910.169(a)(2) (i) is appropriate where the air receiver has no bottom or side drain and is subject to corrosion and is covered by Paragraphs U-1 Scope and 29 CFR 1910.169(a)(1) Application.

OSHA Instruction STD 1-10.2 OCT 30, 1978 -3-

5. Effective Date

This directive is effective immediately and shall be retained until further notice.

Richard P. Wilson Deputy Director, Federal Compliance and State Programs

DISTRIBUTION A-1 E-1 B-2 HEW-1 C-2 NIOSH Regional Program Directors-1 D-4 & 5 NACOSH-1 Training Institute-4

(Originator:OCCS)