[Code of Federal Regulations]

[Title 24, Volume 5]

[Revised as of April 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 24CFR3280.704]



[Page 181-183]

 

                 TITLE 24--HOUSING AND URBAN DEVELOPMENT

 

 CHAPTER XX--OFFICE OF ASSISTANT SECRETARY FOR HOUSING--FEDERAL HOUSING 

        COMMISSIONER, DEPARTMENT OF HOUSING AND URBAN DEVELOPMENT

 

PART 3280_MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS--Table 

of Contents

 

           Subpart H_Heating, Cooling and Fuel Burning Systems

 

Sec.  3280.704  Fuel supply systems.



    (a) LP--Gas system design and service line pressure. (1) Systems 

shall be of the vapor-withdrawal type.

    (2) Gas, at a pressure not over 14 inches water column (\1/2\ psi), 

shall be delivered from the system into the gas supply connection.

    (b) LP-gas containers--(1) Maximum capacity. No more than two 

containers having an individual water capacity of not more than 105 

pounds (approximately 45 pounds LP-gas capacity), shall be installed on 

or in a compartment of any manufactured home.

    (2) Construction of containers. Containers shall be constructed and 

marked in accordance with the specifications for LP-Gas Containers of 

the U.S. Department of Transportation (DOT) or the Rules for 

Construction of Pressure Vessels 1986, ASME Boiler and Pressure Vessel 

Code section VIII, Division 1 ASME Containers shall have a design 

pressure of at least 312.5 psig.

    (i) Container supply systems shall be arranged for vapor withdrawal 

only.

    (ii) Container openings for vapor withdrawal shall be located in the 

vapor space when the container is in service or shall be provided with a 

suitable internal withdrawal tube which communicates with the vapor 

space on or near the highest point in the container when it is mounted 

in service position, with the vehicle on a level surface. Containers 

shall be permanently and legibly marked in a conspicuous manner on the 

outside to show the correct mounting position and the position of the 

service outlet connection. The method of mounting in place shall be such 

as to minimize the possibility of an incorrect positioning of the 

container.

    (3) Location of LP-gas containers and systems. (i) LP-gas containers 

shall not be installed, nor shall provisions be made for installing or 

storing any LP-gas container, even temporarily, inside any manufactured 

home except for listed, completely self-contained hand torches, 

lanterns, or similar equipment with containers having a maximum water 

capacity of not more than 2\1/2\ pounds (approximately one pound LP-gas 

capacity).

    (ii) Containers, control valves, and regulating equipment, when 

installed, shall be mounted on the ``A'' frame of the manufactured home, 

or installed in a compartment that is vaportight to the inside of the 

manufactured home and accessible only from the outside. The compartment 

shall be ventilated at top and bottom to facilitate diffusion of vapors. 

The compartment shall be ventilated with two vents having an aggregate 

area of not less than two percent of the floor area of the compartment 

and shall open unrestricted to the outside atmosphere. The required 

vents shall be equally distributed between the floor and ceiling of the 

compartment. If the lower vent is located in the access door or wall, 

the bottom edge of the vent shall be flush with the floor level of the 

compartment. The top vent shall be located in the access door or wall 

with the bottom of the vent not more than 12 inches below the ceiling 

level of the compartment. All vents shall have an unrestricted discharge 

to the outside atmosphere. Access doors or panels of compartments shall 

not be equipped with locks or require special tools or knowledge to 

open.

    (iii) Permanent and removable fuel containers shall be securely 

mounted to prevent jarring loose, slipping or rotating and the 

fastenings shall be designed and constructed to withstand static loading 

in any direction equal to twice the weight of the tank and attachments 

when filled with fuel, using a safety factor of not less than four based 

on the ultimate strength of the material to be used.

    (4) LP-gas container valves and accessories. (i) Valves in the 

assembly of a two-cylinder system shall be arranged so that replacement 

of containers can be made without shutting off the flow of gas to the 

appliance(s). This provision is not to be construed as requiring an 

automatic change-over device.

    (ii) Shutoff valves on the containers shall be protected as follows, 

in transit, in storage, and while being moved into final utilization by 

setting into a



[[Page 182]]



recess of the container to prevent possibility of their being struck if 

container is dropped upon a flat surface, or by ventilated cap or 

collar, fastened to the container, capable of withstanding a blow from 

any direction equivalent to that of a 30-pound weight dropped 4 feet. 

Construction shall be such that the blow will not be transmitted to the 

valve.

    (iii) [Reserved]

    (iv) Regulators shall be connected directly to the container shutoff 

valve outlets or mounted securely by means of a support bracket and 

connected to the container shutoff valve or valves with listed high 

pressure connections. If the container is permanently mounted the 

connector shall be as required above or with a listed semi-rigid tubing 

connector.

    (5) LP-gas safety devices. (i) DOT containers shall be provided with 

safety relief devices as required by the regulations of the U.S. 

Department of Transportation. ASME containers shall be provided with 

relief valves in accordance with subsection 221 of the Standard for the 

Storage and Handling Liquefied Petroleum Gases, NFPA No. 58-1992. Safety 

relief valves shall have direct communication with the vapor space of 

the vessel.

    (ii) The delivery side of the gas pressure regulator shall be 

equipped with a safety relief device set to discharge at a pressure not 

less than two times and not more than three times the delivery pressure 

of the regulator.

    (iii) Systems mounted on the ``A'' frame assembly shall be so 

located that the discharge from the safety relief devices shall be into 

the open air and not less than three feet horizontally from any opening 

into the manufactured home below the level of such discharge.

    (iv) Safety relief valves located within liquefied petroleum gas 

container compartments may be less than three feet from openings 

provided the bottom vent of the compartment is at the same level or 

lower than the bottom of any opening into the vehicle, or the 

compartment is not located on the same wall plane as the opening(s) and 

is at least two feet horizontally from such openings.

    (6) LP-gas system enclosure and mounting. (i) Housings and 

enclosures shall be designed to provide proper ventilation at least 

equivalent to that specified in Sec.  3280.704(b)(3)(ii).

    (ii) Doors, hoods, domes, or portions of housings and enclosures 

required to be removed or opened for replacement of containers shall 

incorporate means for clamping them firmly in place and preventing them 

from working loose during transit.

    (iii) Provisions shall be incorporated in the assembly to hold the 

containers firmly in position and prevent their movement during transit.

    (iv) Containers shall be mounted on a substantial support or a base 

secured firmly to the vehicle chassis. Neither the container nor its 

support shall extend below the manufactured home frame.

    (c) Oil tanks--(1) Installation. Oil tanks and listed automatic 

pumps (oil lifters) installed for gravity flow of oil to heating 

equipment shall be installed so that the top of the tank is no higher 

than 8 feet above the appliance oil control and the bottom of the tank 

is not less than 18 inches above the appliance oil control.

    (2) Auxiliary oil storage tank. Oil supply tanks affixed to a 

manufactured home shall be so located as to require filling and draining 

from the outside and shall be in a place readily available for 

inspection. If the fuel supply tank is located in a compartment of a 

manufactured home, the compartment shall be ventilated at the bottom to 

permit diffusion of vapors and shall be insulated from the structural 

members of the body. Tanks so installed shall be provided with an 

outside fill and vent pipe and an approved liquid level gage.

    (3) Shutoff valve. A readily accessible, approved manual shutoff 

valve shall be installed at the outlet of an oil supply tank. The valve 

shall be installed to close against the supply.

    (4) Fuel oil filters. All oil tanks shall be equipped with an 

approved oil filter or strainer located downstream from the tank shutoff 

valve. The fuel oil filter or strainer shall contain a sump with a drain 

for the entrapment of water.



[40 FR 58752, Dec. 18, 1975. Redesignated at 44 FR 20679, Apr. 6, 1979, 

as amended at 47 FR 49390, Nov. 1, 1982; 52 FR 4587, Feb. 12, 1987; 58 

FR 55016, Oct. 25, 1993]



[[Page 183]]





    Effective Date Note: At 70 FR 72050, Nov. 30, 2005, Sec.  3280.704 

was amended by revising paragraph (b)(5)(i), effective May 30, 2006. For 

the convenience of the user the revised text follows:



Sec.  3280.704  Fuel supply systems.



                                * * * * *



    (b) * * *

    (5) LP-gas safety devices. (i) DOT containers must be provided with 

safety relief devices as required by the regulation of the U.S. 

Department of Transportation. ASME containers must be provided with 

relief valves in accordance with subsection 2.3.2 of NFPA 58-2001, 

Standard for the Storage and Handling Liquefied Petroleum Gases. Safety 

relief valves must have direct communication with the vapor space of the 

vessel.



                                * * * * *