48 CFR § 211.170
Use of proprietary specifications or standards
November 17, 2020
A justification and approval is required to use proprietary specifications and standards—
(1) When using sealed bidding or negotiated acquisition procedures (see 206.302-1(S-70) for justification requirements); or,
(2) When using the simplified procedures for certain commercial items at FAR 13.5 (see 213.501(a)(ii) for justification requirements).
[84 FR 25192, May 31, 2019]