46 CFR § 153.1025 - Motor fuel antiknock compounds.
(a) No person may load or carry any other cargo in a containment system approved for motor fuel antiknock compounds containing lead alkyls except a cargo to be used solely in the manufacture of motor fuel antiknock compounds.
(1) The pumproom or void space atmosphere has been analyzed for its lead (as Pb) content and found to be less than 0.075 mg/m 3; or
(c) No person may enter a cargo tank endorsed for motor fuel antiknock compounds containing lead alkyls without prior specific authorization from the Commandant (CG-ENG). This authorization may be obtained by calling telephone number 202-372-1420 or e-mail firstname.lastname@example.org if the person has previously obtained approval for the cargo tank entry procedure from the Commandant (CG-ENG).