(a) Fireworks devices that require a fuse shall:(1) Utilize only a fuse that has been treated or coated in such manner as to reduce the possibility of side ignition. Devices such as ground spinners that require a restricted orifice for proper thrust and contain less than 6 grams of pyrotechnic composition are exempted from § 1507.3(a)(1) .(2) Utilize only a fuse which will burn at least 3 seconds but not more than 9 seconds before ignition of the device.(b) The fuse shall be securely attached so that it will support either the weight of the fireworks device plus 8 ounces of dead weight or double the weight of the device, whether is less, without separation from the fireworks device.41 FR 22935, June 8, 1976, as amended at 61 FR 67200, Dec. 20, 1996; 61 FR 67200, Dec. 20, 1996