USG-13 is the state variation for the United States of America. This variation calls for further limitation to the amount of dangerous goods that can be loaded aboard a passenger aircraft in an inaccessible manner. This regulation is based on 49 CFR, Parts 171-180. This requirement is for all passenger aircraft that transport dangerous goods to, from or within the United States.
Consignments must not contain more than 25 kg of dangerous goods or 75 kg net quantity of non-flammable gas. For liquid dangerous goods for the purpose of this regulation 1 liter = 1 kg. Irrespective of limitations for PAX flights in IATA Dangerous Goods Regulations these limitations are mandatory.
Explosives division 1.4S, UN0012, UN0014 and UN0055 also meeting the requirements of 173.63(b)
Class 9 (examples ID8000), this does not include UN3480 or UN3090
UN3528 and UN3529
Dangerous goods in limited quantities
Dangerous goods in excepted quantities
Aircraft batteries transported as items of replacement (CFR49 175.8 also see IATA special provision A51)
Dangerous goods under IATA DGR regulations which are not subject to CFR49 Parts 171-180