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Interpretation Response #11-0060 ([National Electrical Manufacturers Association] [Mr. Craig Updyke])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: National Electrical Manufacturers Association

Individual Name: Mr. Craig Updyke

Location State: VA Country: US

View the Interpretation Document

Response text:

July 7, 2011




Mr. Craig Updyke

Manager, Trade & Commercial Affairs

1300 North 17th St., Suite 1752

National Electrical Manufacturers Association

Rosslyn, VA 22209

Reference No. 11-0060

Dear Mr. Updyke,

This is in response to your request for clarification of the Hazardous Materials Regulations (HMR; 49 CFR, Parts 171-180) applicable to the transportation by highway of fuel tanks on mobile generators. Your questions are paraphrased and answered below.

Q1. What are the HMR requirements for the transportation of fuel tanks on "mobile generator sets" ("gensets")? The fuel tanks have varying capacities, from 160 gallons to 1,400 gallons for diesel fuel.

A1. If by "mobile generator sets" you mean portable generators, provided the fuel tanks are securely closed, the portable generators are not otherwise subject to the HMR when being transported by motor vehicle and rail when the fuel tank contains more than 500 mL (17 ounces) of liquid fuel. Also see § 173.220(h). The § 173.220 (b)(4)(i) modal exceptions for transportation by motor vehicle and rail provide for quantities of flammable liquid fuel greater than 500 mL (17 ounces) to remain in the fuel tank in self-propelled vehicles and mechanical equipment if the fuel tanks are securely closed.

If the fuel tanks are empty, unless other hazardous materials that are subject to the HMR are involved, the generator is not subject to the HMR, including the requirement for fuel tanks to be securely closed. Under the HMR, a fuel tank is considered empty when the fuel tank and the fuel lines have been completed drained, sufficiently cleaned of residue, and purged of vapors to remove any potential hazard (see § 173.220(a)(2)).

Q2. Are there any exemptions or "alternate regulatory approach" to the transportation of fuel tanks on mobile generators?

A2. With respect to portable generators being transported by motor vehicle, the modal exceptions in § 173.220 make regulatory options unnecessary (see A1).

Q3. Does PHMSA or state regulators have jurisdiction for regulating portable generators?

A3. PHMSA has jurisdiction for regulating the transportation of portable generators in commerce. States must adopt regulations that are comparable to, and do not conflict with, the HMR.

Q4. How should Canada"s recent amendment to the original Transportation of Dangerous Goods Act of 1992 be interpreted or addressed?

A4. Interpretations pertaining to Canadian regulations should be directed to Linda Hume at Transport Canada, TDG Canadian Government Publishing Center, Supply and Services, Canada, Ottawa, Ontario, Canada K1A, 059, 416"973"1868, Ms. Hume"s e-mail address is .

I hope this information is helpful. Please contact this office should you have additional questions.


T. Glenn Foster

Chief, Regulatory Review and Reinvention

Standards and Rulemaking Division


Regulation Sections

Section Subject
173.220 Internal combustion engines, vehicles, machinery containing internal combustion engines, battery-powered equipment or machinery, fuel cell-powered equipment or machinery