N.Y. Comp. Codes R. & Regs. tit. 21 § 1401.5 : Miscellaneous — Committee On Open Government — Public Access To Records Of State And Local Agencies, Including Counties, Cities, Towns, Villages, School Districts And Fire Districts — Responses to requests for records

(a) An agency may require that a request be made in writing or may make records available upon oral request.
(b) When an agency maintains requested records on the internet, a response shall inform a requester that the records are accessible via the internet and in printed form either on paper or other information storage medium.
(c) An agency shall respond to a request within five business days of the receipt of a request by:
(1) informing a person requesting records that the request or portion of the request does not reasonably describe the records sought, including direction, to the extent possible, that would enable that person to request records reasonably described;
(2) granting or denying access to records in whole or in part;
(3) acknowledging the receipt of a request in writing, including an approximate date when the request will be granted or denied in whole or in part, which shall be reasonable under the circumstances of the request and shall not be more than 20 business days after the date of the acknowledgment, or if it is known that circumstances prevent disclosure within 20 business days from the date of such acknowledgment, providing a statement in writing stating the reason for inability to grant the request within that time and a date certain, within a reasonable period under the circumstances of the request, when the request will be granted in whole or in part; or
(4) if the receipt of request was acknowledged in writing and included an approximate date when the request would be granted in whole or in part within 20 business days of such acknowledgment, but circumstances prevent disclosure within that time, providing a statement in writing with 20 business days of such acknowledgment stating the reason for the inability to do so and a date certain, within a reasonable period under the circumstances of the request, when the request will be granted in whole or in part.
(d) In determining a reasonable time for granting or denying a request under the circumstances of a request, agency personnel shall consider the volume of a request, the ease or difficulty in locating, retrieving or generating records, the complexity of the request, the need to review records to determine the extent to which they must be disclosed, the number of requests received by the agency, and similar factors that bear on an agency's ability to grant access to records promptly and within a reasonable time.
(e) A failure to comply with the time limitations described herein shall constitute a denial of a request that may be appealed. Such failure shall include situations in which an agency:
(1) fails to grant access to the records sought, deny access in writing or acknowledge the receipt of a request within five business days of the receipt of a request;
(2) acknowledges the receipt of a request within five business days but fails to furnish an approximate date when it will grant or deny a request in whole or in part;
(3) furnishes an acknowledgment of the receipt of a request within five business days with an approximate date for granting or denying access in whole or in part that is unreasonable under the circumstances of the request;
(4) fails to respond to a request within a reasonable time after the approximate date given or within 20 business days after the date of its acknowledgment of the receipt of a request;
(5) determines to grant a request in whole or in part within 20 business days of its acknowledgment of the receipt of a request, but fails to do so, unless the agency provides the reason for its inability to do so in writing and a date certain within which the request will be granted in whole or in part;
(6) does not grant a request in whole or in part within 20 business days of its acknowledgment of the receipt of a request and fails to provide the reason in writing explaining its inability to do so and a date certain by which the request will be granted in whole or in part; or
(7) responds to a request, stating that more than 20 business days is needed to grant or deny the request in whole or in part and provides a date certain within which it will do so, but such date is unreasonable under the circumstances of the request.

N.Y. Comp. Codes R. & Regs. Tit. 21 § 1401.5