N.Y.C. Admin. Code § 20-613: § 20-613 Posting notice.

Every dealer of etching acid shall conspicuously post at every table, desk or counter where orders are placed and/or payment is made a notice, the form and manner of which are to be provided by rule of the commissioner, indicating that all purchasers of etching acid shall be required to provide valid photo identification and their personal information and such information shall be recorded by the dealer of etching acid prior to purchase.