(a) Request for admission.

(1) Any party may serve upon any other party a request for admission of any relevant matter or the authenticity of any relevant document. Copies of any document about which an admission is requested must accompany the request.

(2) Each matter for which an admission is requested shall be separately set forth and numbered. The matter is admitted unless within 15 days after service of the request, the party to whom the request is directed serves upon the party requesting the admission a written answer signed by the party or his/her attorney.

(3) Each answer must specify whether the party admits or denies the matter. If the matter cannot be admitted or denied, the party shall set out in detail the reasons.

(4) A party may not issue a denial or fail to answer on the ground that he/she lacks knowledge unless he/she has made reasonable inquiry to ascertain information sufficient to allow him/her to admit or deny.

(5) A party may file an objection to a request for admission within 10 days after service. Such motion shall be filed with the administrative law judge if one has been appointed, otherwise it shall be filed with the Assistant Administrator. An objection must explain in detail the reasons the party should not answer. A reply to the objection may be served by the party requesting the admission within 10 days after service of the objection. It is not sufficient ground for objection to claim that the matter about which an admission is requested presents an issue of fact for hearing.

(b) Effect of admission. Any matter admitted is conclusively established unless the Assistant Administrator or administrative law judge permits withdrawal or amendment. Any admission under this rule is for the purpose of the pending action only and may not be used in any other proceeding.

(c) If a party refuses to admit a matter or the authenticity of a document which is later proved, the party requesting the admission may move for an award of expenses incurred in making the proof. Such a motion shall be granted unless there was a good reason for failure to admit.