N.Y. Comp. Codes R. & Regs. tit. 21 § 1211.70
Spirits of nitroglycerin is restricted to a maximum quantity per vehicle [FN*] of one quart when in inside glass containers, and six quarts when in inside metal containers. There are no restrictions on the transport of empty containers which last contained spirits of nitroglycerin provided the accompanying shipping papers show that they are drained of the liquid and securely closed.
[FN*] A tank vehicle used for the transportation of any flammable liquid, regardless of the quantity being transported, or whether loaded or empty, shall not enter either a tunnel, the George Washington Bridge Lower Level or George Washington Bridge Expressway; nor shall an empty tank vehicle containing residue of cut-back tar or cement or of any other substance thinned with a flammable liquid enter said facilities. A new tank vehicle, however, which has never been used for the transportation of a flammable liquid is allowed passage provided it is accompanied by an invoice, or other shipping paper, stating that the tank vehicle has never been so used.
N.Y. Comp. Codes R. & Regs. Tit. 21 § 1211.70