---
kind: "section"
citation: "42 C.F.R. § 84.252"
title: "42"
number: "84.252"
heading: "Gas masks; requirements and tests."
url: "https://uscodex.org/cfr/42/84.252"
---

# §84.252. Gas masks; requirements and tests.

- (a) Except for the tests prescribed in [§ 84.126](/cfr/42/84.126.md), the minimum requirements and performance tests for gas masks, prescribed in [Subpart I](/cfr/42/subpartI.md) of this part, are applicable to vinyl chloride gas masks.
- (b) The following bench tests are applicable to canisters designed for use with gas masks for entry into and escape from vinyl chloride atmospheres containing adequate oxygen to support life:
  - (1) Four canisters will be equilibrated at 25 ±5 °C by passing 85 ±5 percent relative humidity air through them at 64 liters per minute for six hours.
  - (2) The equilibrated canisters will be resealed, kept in an upright position at room temperature, and tested according to [paragraph (b)(3)](#b-3) of this section within 18 hours.
  - (3) The canisters equilibrated and stored as described in [paragraphs (b)](#b) (1) and (2) of this section will be tested on an apparatus that allows the test atmosphere at 85 ±5 percent relative humidity and 25 ±5 °C to enter the canister continuously at a concentration of 25 ppm vinyl chloride monomer at a total flow rate of 64 liters per minute.
  - (4) The maximum allowable penetration after six hours of testing according to [paragraph (b)(3)](#b-3) of this section shall not exceed 1 ppm vinyl chloride.
- (c) Where canisters are submitted for testing and approval with a service life of more than four hours, the period of time for testing for vinyl chloride penetration will be performed at 150% of the service life specified in the manufacturer's application. (Example: If a manufacturer requests approval of a respirator for six hours use against exposure to vinyl chloride, the maximum allowable penetration after nine hours of testing shall not exceed 1 ppm vinyl chloride.)

## Notes

### Authority

Authority: 29 U.S.C. 651 et seq.; 30 U.S.C. 3, 5, 7, 811, 842(h), 844.

### Source

Source: 60 FR 30355, June 8, 1995, unless otherwise noted.