23 CFR §636.303

1. (a)If you use a prequalification procedure or a two-phase selection procedure to develop a short list of qualified offerors, then pre-qualification criteria should not be included as proposal evaluation criteria.
2. (b)The proposal evaluation criteria should be limited to the quality, quantity, value and timeliness of the product or service being proposed. However, there may be circumstances where it is appropriate to include prequalification standards as proposal evaluation criteria. Such instances include situations where:
   1. (1)The scope of work involves very specialized technical expertise or specialized financial qualifications; or
   2. (2)Where prequalification procedures or two-phase selection procedures are not used (short listing is not performed).