(a) When a request is made in person, subject to the provisions of section 339.6(a) of this Part, or when records are made available in person following a request made by mail, the department shall require appropriate identification such as a driver's license, an identifier assigned to the data subject by the department, a photograph identification or similar information that confirms that the record sought pertains to the data subject.

(b) When a request is made by mail, the department shall require verification of a signature or inclusion of an identifier generally known only by a data subject or other appropriate identification.

(c) Proof of identity shall not be required regarding a request for a record accessible to the public pursuant to article 6 of the Public Officers Law.