[Federal Register Volume 65, Number 89 (Monday, May 8, 2000)]
[Notices]
[Pages 26657-26658]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 00-11375]


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DEPARTMENT OF TRANSPORTATION

Research and Special Programs Administration

[RSPA-00-7283, Notice No. 00-4]


Safety Advisory Notice; Use of Non-Complying Portable Tanks for 
Transportation of Propane

AGENCY: Research and Special Programs Administration (RSPA), DOT.

ACTION: Safety advisory notice.

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SUMMARY: This safety advisory notice is to make persons aware of safety 
concerns related to the intermodal transportation of propane in 
portable tanks and of the proper packaging requirements for such 
transportation. RSPA has become aware of several instances where 
propane was improperly transported in portable tanks. This suggests 
that some persons who offer or transport propane in portable tanks may 
not be fully aware of the applicable requirements of the Hazardous 
Materials Regulations. This notice alerts offerors and transporters to 
potential safety problems and summarizes the proper packaging 
requirements for offering or accepting propane in portable tanks for 
transportation.

FOR FURTHER INFORMATION CONTACT: Diane LaValle, Office of Hazardous 
Materials Standards, RSPA, Department of Transportation, 400 Seventh 
Street, SW., Washington, DC 20590-0001, Telephone (202) 366-8553.

SUPPLEMENTARY INFORMATION:

I. Background

    The U.S. Coast Guard has identified problems with certain portable 
tanks used to transport propane in and between the states of Washington 
and Alaska. It appears that many of the portable tanks in this service 
may not conform to the requirements of the Hazardous Materials 
Regulations (HMR; 49 CFR parts 171-180) and to requirements for 
approval and inspection of cargo containers (49 CFR parts 450-453). 
Some of the deficiencies identified may pose a significant safety 
threat.
    On March 17, 2000, a SeaLand/CSX cargo vessel transporting over 
6,000 gallons of propane in a portable tank encountered rough seas. The 
portable tank broke loose from its frame, damaging its external piping 
and releasing over 100 gallons of propane. Although the release of 
propane in this incident was relatively small, the potential for a 
catastrophic incident involving the bulk transportation of propane on 
board vessels should not be minimized. A significant release of 
propane, coupled with a fire or explosion, would place the crew and the 
vessel at serious risk.
    Subsequent inquiries and investigations by RSPA's Offices of 
Hazardous Materials Enforcement and Hazardous Materials Technology, the 
Federal Motor Carrier Safety Administration, and the U.S. Coast Guard 
identified several potential problems with portable tanks used for the 
intermodal transportation of propane. These problems involve improper 
mounting of portable tanks to container frames, substandard welds where 
portable tanks are attached to container frames, overfilling, 
improperly modified cargo tanks, and invalid specification packaging 
markings. Preliminary indications are that such deficiencies may affect 
a significant number of portable tanks in intermodal propane service. 
An initial industry estimate is that perhaps 60 percent of 500 portable 
tanks involved in this transportation may not conform to HMR 
requirements. Because these tanks are used in intermodal service, the 
potential safety problems could affect highway and rail transportation, 
in addition to transportation by vessel.

II. Requirements for the Transportation of Propane in Portable 
Tanks

    Section 173.315 of the HMR authorizes the transportation of propane 
in a number of bulk packagings, including DOT Specification 51 portable 
tanks. Specifications for the design and manufacture of DOT 
Specification 51 portable tanks are in Subpart H of Part 178 of the 
HMR.
    Design and construction. Generally, DOT 51 portable tanks must be 
designed, constructed, certified, and stamped in accordance with the 
ASME Code in effect at the time the tank is constructed (see 
Sec. 178.245-1). Welds used in tank construction, as well as welding 
procedures and weld performance tests, must conform to the ASME Code 
(see Sec. 178.245-1(b)). The regulations also include specific 
requirements for tank openings and filling and discharge connections 
(see Sec. 178.245-1(d)). Among other requirements, each filling and 
discharge connection below the normal liquid level of the tank must be 
equipped with an internal self-closing stop valve capable of closing 
within 30 seconds of actuation.
    The regulations for DOT 51 portable tanks also include specific 
requirements applicable to materials of construction (Sec. 178.245-2), 
design pressure (Sec. 178.245-3), mountings (Sec. 178.245-4), and 
damage protection (Sec. 178.245-5).
    A DOT 51 portable tank that meets the definition of a ``container'' 
in 49 CFR 450.3(a)(2) must also conform to the requirements of 49 CFR 
parts 450 through 453 for compliance with Annex II of the International 
Convention for Safe Containers, particularly with regard to attachment 
of the portable tank to its intermodal frame (see Sec. 178.245-
1(d)(4)(i) and 178.245-4(e)). Parts 450 through 453 establish 
requirements and procedures for safety approval and periodic 
examination of cargo containers. Portable tanks that meet the 
definition of ``container'' for purposes of Parts 450 through 453 must 
be inspected by an agency that has been approved by the US Coast Guard. 
As defined in 49 CFR 450.3(a)(2), a ``container'' is an article of 
transport equipment that: (1) Is suitable for repeated use; (2) is 
designed to facilitate the transport of goods by one or more modes of 
transport without intermediate reloading; (3) is designed to be secured 
and readily handled with corner fittings for these purposes; and (4) 
has an area enclosed by the bottom four corners that is at least 150 
square feet or 75 square feet if it has top corner fittings.
    Periodic inspections and tests. Portable tanks used for the 
transportation of hazardous materials must undergo periodic inspections 
and tests to assure the continued integrity of the tank and its 
appurtenances. The requirements for periodic inspection and testing of 
DOT 51 portable tanks are in Sec. 173.32(e). Every five years, a DOT 51 
portable tank must successfully pass a pressure test that conforms to 
the requirements in Sec. 173.32(e)(2)(i) and a visual inspection that 
conforms to the requirements in Sec. 173.32(e)(2)(ii). The date of the 
most recent periodic test and inspection must be marked on the tank on 
or near its certification plate. A portable tank for which the 
prescribed tests or inspections have become due may not be filled and 
offered for

[[Page 26658]]

inspection until the test or inspection has been successfully 
completed.
    Cargo tank conversions. It is possible, though difficult, to modify 
a cargo tank, such as by using the tank from an MC 330 cargo tank motor 
vehicle, to meet the DOT 51 portable tank specification. The 
modification must be performed by an ASME Code facility. The 
manufacturer performing the modification must assure that the modified 
tank conforms to all the requirements of the DOT 51 specification in 
Sec. 178.245 of the HMR. Such a tank no longer meets the cargo tank 
specification; thus, the manufacturer must remove or cover the cargo 
tank specification plate on the modified tank and affix a new 
certification plate in accordance with Sec. 178.245-6. Other than 
through recertification as a portable tank, there is no provision for 
use of the tank from a cargo tank motor vehicle as a portable tank.
    Filling densities. The HMR prescribe maximum permitted filling 
densities for portable tanks in propane service in Sec. 173.315(b). 
Generally, maximum permitted filling densities depend on the specific 
gravity of the material to be transported, measured at 60 deg.F, and 
the size of the tank. Propane in a portable tank may not exceed 60 
percent of the water-weight capacity of the tank.

III. Safety Implications

    The purpose of this safety advisory notice is to alert persons who 
offer or transport propane that transporting propane in portable tanks 
that do not conform to the HMR could have serious safety implications 
for persons who handle or transport such tanks and for the general 
public. When liquid propane is released into the atmosphere, it quickly 
vaporizes into the gaseous form that is its normal state at atmospheric 
pressure. Vaporization occurs very rapidly and, in the process, the 
propane combines readily with air to form fuel-air mixtures that are 
ignitable over a range of 2.2 to 9.5 percent by volume. If an ignition 
source is present in the vicinity of the highly flammable mixture, the 
vapor cloud ignites and burns explosively.
    No person may offer for transportation or transport hazardous 
materials except in conformance with the HMR. Persons offering or 
transporting propane in portable tanks that do not conform to the HMR 
requirements may be subject to civil or criminal penalties.

    Issued in Washington, DC, on May 2, 2000.
Robert A. McGuire,
Acting Associate Administrator for Hazardous Materials Safety.
[FR Doc. 00-11375 Filed 5-5-00; 8:45 am]
BILLING CODE 4910-60-P