You are viewing an archived code
Loading...
When tank cars are located on a dead-end siding, they shall be protected from any oncoming car by a locked switch which shall positively prevent collision with the tank car. If on an open siding, tank cars shall be protected by locked switches at both ends. Locked switches shall be located not less than 15 feet from either or both ends of tank cars. Keys for switches shall be available only to persons having certificates of fitness.
If unloading operations are carried on at night, an approved vaporproof red electric light shall be installed at the location of each locked switch and shall be kept lighted at all times when the tank car is connected to the unloading line.
(Coun. J. 12-9-92, p. 25465; Amend Coun. J. 2-7-96, p. 15616)
Minimum tank car safety clearances from adjacent buildings or structures shall be in accordance with the following table:
Nature of Building Construction | Min. Distance With Fender Wall | Min. Distance Without Fender Wall |
External walls of fire-resistive construction – no openings | 15' | 25' |
External walls of fire-resistive construction – with openings | 25' | 50' |
External walls not of fire-resistive construction | 50' | 75' |
“Minimum distance” refers to distance between centerline of track and exterior face of building wall.
“No openings” means no windows, doors or other openings in wall opposite car for a distance equal to the length of the car plus 15 feet on both ends and for a height of 25 feet above tank car rail elevation.
“Fender wall” refers to a freestanding wall five feet longer at each end than the length and five feet higher than the greatest height of the tank cars to be used and shall be interposed between the tank car track and such building. The wall shall be of four-hour fire-resistive construction and shall have a fender or return wall at each end of the same height and thickness and extending at least three feet on the tank car side of such fender wall. It shall be located parallel to the siding and its centerline shall be not less than eight feet and not more than fifteen feet from the centerline of the track.
The minimum tank car safety clearances shall be construed to require a space open its entire area to the sky and shall apply to property dividing lines or adjacent property which may be built upon, to adjoining and adjacent public ways, and to any main line of a steam, electric or elevated railway or any other railway right-of-way.
(Coun. J. 12-9-92, p. 25465; Amend Coun. J. 2-7-96, p. 15616)
If the licensee does not have a private switch engine available at all times to withdraw the tank cars in event of impeding damage to the car, he may be required to install an approved car puller which can be used to pull the car to a position of safety.
(Coun. J. 12-9-92, p. 25465; Amend Coun. J. 2-7-96, p. 15616)
Tank cars shall be unloaded through piping systems which comply with the following requirements:
Extra-heavy wrought steel pipe (ASTM Schedule 80) shall be used for all liquefied gas lines and no such pipe shall be larger than one and one-half inches nominal diameter. All joints shall be welded whenever possible. If flanges are required, they shall be of the 300-pound forged steel ammonia-type properly welded to the pipe with a continuous bead. Gaskets shall be of a material chemically resistant to the fluid in the line and suitable for the pressures and temperatures involved. Fittings shall be forged steel socket welding- type designed for temperatures and pressures to be encountered. Valves shall be of a type specifically designed and manufactured for the particular liquefied gas involved and shall be for a 300-pound minimum operating pressure. One valve shall be placed in the line near the car in an accessible position, and one valve shall be installed immediately before the line enters the building in which such gas is to be used. In addition, one valve shall be provided for each 200 feet of line, one and one-half inches in diameter or smaller. Where piping is exposed to variations in temperature, provisions shall be made for expansion of the piping and for the liquid in the line. One or more expansion loops shall be installed to provide for expansion of the pipe. The number of loops to be provided shall be calculated on the length of the line and extremes of temperature to which the line will be exposed. Adequate anchors shall be provided so that expansion will be in the directions desired. To provide for liquid expansion, one or more expansion chambers shall be installed depending on the length of line. The expansion chamber shall be in accordance with ASME standards for pressure vessels of a size approximately equal to a 150-pound gas cylinder. One such chamber shall be provided for each 500 feet of line of one and one-half inch pipe size or smaller. The expansion chambers shall be inverted over the line and enclosed in an insulated box maintained at a temperature in excess of the critical temperature of the gas involved, at the operating pressure used. The unloading line shall be connected to the car by a semiflexible gooseneck or helical pipe connection that is flanged at one or both ends for connecting and disconnecting. Flexible connections shall be adequately supported and protected against damage.
Overhead lines shall be supported on steel, concrete columns or other noncombustible structures in a manner to conform with the code for pressure piping as approved by the American Society of Mechanical Engineers and American National Standards Institute. All horizontal lines and supporting structures shall have a minimum clearance of 23 feet over all roadways, over railroad rights-of-way and in other locations where they may be endangered by moving objects. In all other locations the minimum clearance between horizontal lines and supporting structures and the ground shall be 15 feet unless such lines are adequately protected from damage by a building of fire-resistive construction. All vertical and inclined risers at tank cars and at all other points where horizontal lines change from one elevation to another shall be protected by running them against the web of a wide flange beam weighing not less than 30 pounds per foot. In every case the web of the beam shall be between the pipe and the direction from which it might be struck. Such protective beams shall be supported and anchored so as to afford complete protection against damage to the pipeline.
Underground lines shall be installed in an approved reinforced concrete trench, drained and with removable covers. In lieu of the concrete trench, where not feasible or desirable, the steel conductor pipe shall be protected in the ground by a pipe having pressure-tight joints, acting as a continuous sleeve, fabricated of a material which will not be deteriorated unduly by any chemicals in the soil in which it is located. The conductor pipe and sleeve shall be installed sufficiently deep in the ground to protect against damage from loading on the surface of the ground. The pipe sleeve shall be sealed to the conductor pipe at its ends outside of the ground either by welding the sleeve to the conductor pipe or by a pressure-tight lead-caulked joint.
A pressure gauge shall be provided which will indicate pressure inside the sleeve in event of a leak in the conductor pipe. A compressed air pressure connection shall also be provided by which the sleeve can be tested for tightness. The vertical pipe from the flexible connection at the tank car to the ground shall be protected against damage by a steel beam as previously described.
Welding procedures shall be qualified under the regulations of the latest edition of the American National Standard Code for Pressure Piping, ANSI B-31.1, and shall meet the approval of the fire commissioner. Certificates of each welder's qualifications shall be presented before any work is started.
(Coun. J. 12-9-92, p. 25465; Amend Coun. J. 2-7-96, p. 15616; Amend Coun. J. 5-18-16, p. 24131, § 148)
All exposed piping containing liquefied fume hazard gas located within or outside of a building shall be painted in accordance with ANSI Standard A-13, “Scheme for Identification of Piping Systems”, Class D. The liquid in such piping shall be designated by clear and legible lettering on the pipe, or, if the pipes are too small for legible lettering, by placards securely hung on the pipe. Labeling or placards shall be sufficiently frequent to make identification simple and easy, at all valves, and in each room within a building. Support columns for outdoor piping shall have ample identifying signs warning that piping carries a specific liquefied fume hazard gas and must not be bumped or damaged.
(Coun. J. 12-9-92, p. 25465; Amend Coun. J. 2-7-96, p. 15616)
Adequate approved electric lighting shall be provided in all areas where unloading, connecting, disconnecting and valving operations are to be performed or where fume hazard gases are used or stored.
Tank cars shall be protected from undue heat or open flame. Installation of equipment shall be made to prevent pressure build-up in tank cars beyond normal safe tolerance, in accordance with Recommendations of the Manufacturing Chemist's Association.
Processing equipment shall be located at such an elevation that pressure in excess of tank car pressure shall not be necessary to force the liquid into the equipment.
Pressure in tank cars shall not be increased by introduction of any gas under pressure or by any other means.
(Coun. J. 12-9-92, p. 25465; Amend Coun. J. 2-7-96, p. 15616)
The name and address of the manufacturer or the nearest producer of the specific gas being used and a placard outlining emergency first aid directions shall be posted and remain posted in a conspicuous place at the points of unloading and use and in at least one other approved location.
Adequate oxygen-generating or self-contained air or oxygen masks having a United States Bureau of Mines or National Institute for Occupational Safety and Health approval for a minimum of one-half hour protection shall be maintained in a readily accessible location, outside the areas of probable contamination. Additional air or oxygen containers which will provide for a minimum of one hour use of each mask shall be kept at the location of each gas mask. All personnel that may be required to use gas masks must be required at reasonable intervals to practice their application and use. Gas masks must be kept in condition, ready for immediate use at all times with fully charged containers.
(Coun. J. 12-9-92, p. 25465; Amend Coun. J. 2-7-96, p. 15616)
Loading...