StacksVerified U.S. regulatory reference

16 CFR §1616.3

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
  1. (a)Summary of test method. Conditioned specimens are suspended one at a time vertically in holders in a prescribed cabinet and subjected to a standard flame along their bottom edges for a specified time under controlled conditions. The char lengths are recorded.
  2. (b)Test criteria. The test criteria when the testing is done in accordance with § 1616.4 Sampling and acceptance procedures and § 1616.5 Test procedures are:
    1. (1)Average char length. The average char length of five specimens shall not exceed 17.8 cm. (7.0 in.).
    2. (2)Full-specimen burn. No individual specimen shall have a char length of 25.4±0.5 cm. (10±0.2 in.).
  3. (c)Details of the number of specimens which must meet the above test criteria for unit acceptance is specified in § 1616.4.