PART IVPiping and Transfer Equipment (continued)
44 Unless the installation is enclosed by a wire mesh fence not less than five feet in height and provided with a locked gate, tank shut-off valves shall be shut tight and locked during the absence of the attendant.
(2) Provision shall be made in the piping for expansion, contraction and settling.
(3) Pipeline shall be protected by metal guard rails against damage from trucks and other traffic.
46 (1) Except as provided in subsections (2) and (3), below-ground ammonia lines shall be laid not less than three feet below ground or be enclosed in a reinforced concrete or steel trench with a recessed removable cover which shall be flush with the ground. The trench shall be of sufficient strength to support all traffic which may pass over it and shall be provided with drainage.
(2) Pipelines under roadways on railway property shall be enclosed in an encasing pipe of sufficient strength to support all traffic which may pass over it and shall be not less than three feet below the surface of the roadway.
(3) Pipelines under railways shall be installed in accordance with Pipe Crossings Under Railways (E-10) Regulations.
47 (1) Except for pipelines between adjacent loading or unloading racks, pipelines on the railway right-of-way within 20 feet of the gauge side of the nearest rail of a track shall be laid not less than three feet below ground, or be enclosed in a reinforced concrete or steel trench as prescribed in subsection 46(1), or be carried on an overhead pipe bridge with a clearance above ground of not less than 13 feet, or be enclosed by a fence.
(2) Pipelines running parallel to a track, except those between adjacent unloading or loading racks, shall not be closer than 10 feet to the gauge side of the nearest rail of that track and shall comply with subsection (1).
48 Provision shall be made in loading or unloading lines for relief of pressure before disconnection.
49 When loading or unloading racks are not employed for loading or unloading tank cars, the filling or discharge terminals shall be protected on all sides by a guard rail of metal or other material of equivalent strength and permanence. The guard rail shall be not less than three feet in height.
50 Tank car loading or unloading lines shall be equipped with shut-off valves located at the tank car end of the loading or unloading line. These valves shall not be used for throttling purposes, but shall be either fully open or fully closed in order not to interfere with the operation of excess flow valves on the tank car.
51 All piping inside buildings where anhydrous ammonia is stored or handled shall be grounded to prevent the build-up of static electricity. The resistance to ground shall be as low as possible and preferably not more than six ohms.
52 (1) All piping, valves and fittings shall be inspected and tested after assembly and prior to commencing operations for the first time and be proven gastight at a pressure not less than the working pressure of the tank, pump or device to which they are connected, or at 150 psig if this is a higher pressure.
(2) The results of the piping inspection and test shall be reported to the Commission.
(2) The pump or compressor should be separated from the engine or motor by a fireproof and vapour-proof wall.
(3) Except for the frame, the building shall be constructed of noncombustible or fire-resistant materials.
(4) Engine exhausts shall terminate outside the building.
(5) The building shall be cross-ventilated near the ceiling level.
(6) The entire system shall be maintained in good operating condition at all times.
PART VSafety Relief Devices
54 (1) Each unrefrigerated tank shall be equipped with one or more safety relief valves of the spring loaded type or an equivalent type which have been approved for the intended service by the Boiler and Pressure Vessel Committee of A.S.M.E., or the Compressed Gas Association, Inc., or Underwriters’ Laboratories.
(2) The valves referred to in subsection (1) shall be of a size that will ensure a rate of discharge not less than that specified in the current edition of Agricultural Ammonia Institute pamphlet, Standards for the Storage and Handling of Anhydrous Ammonia.
(3) The rate of discharge prescribed in subsection (2) shall be obtained before the pressure is in excess of 120 per cent of the maximum permitted start to discharge pressure setting of the device.
(4) The rate of discharge for relief valves on refrigerated tanks shall be in accordance with the current edition of Agricultural Ammonia Institute pamphlet, Standards for the Storage and Handling of Anhydrous Ammonia.
(5) Safety relief valves on unrefrigerated tanks shall be set to start to discharge at pressures as prescribed in the current edition of Agricultural Ammonia Institute pamphlet, Standards for the Storage and Handling of Anhydrous Ammonia.
(6) Relief valves on refrigerated containers shall be set to discharge at a pressure not in excess of the design working pressure of the container.
(7) Safety relief valves shall be installed in a manner that will ensure that the full relief requirements are always satisfied.
(2) If the design of the relief system is such that liquid can collect on the discharge side of the disc, the valve shall be equipped with a suitable drain.
(3) Tank safety relief valves shall be vented vertically to the outside atmosphere at a safe location and at least seven feet above the tank; except that for a tank of 2,000 Imperial gallons capacity or less and not provided with a ladder or other means of access to the top, the top of the vent shall not be less than seven feet above ground level.
(4) The end of the vent pipe shall be fitted with a loose rain cap that will not freeze in place.
(5) Safety relief devices shall be so arranged that the possibility of tampering will be minimized.
(6) Return bends and restrictive piping are not permitted in relief valve piping.
(7) External pressure settings or adjustments shall be sealed.
56 Safety relief valves and devices shall be inspected and tested prior to being put into service and shall be retested periodically as prescribed in the Compressed Gas Association pamphlet, Safety Relief Device Standards for Compressed Gas Storage Containers.
57 (1) A safety relief valve venting to the outside atmosphere at a height not less than seven feet above ground level shall be installed between each pair of shut-off valves in an ammonia line where liquid may be trapped. The start to discharge pressure shall not be less than the setting of the container relief valve and not in excess of 400 psig.
(2) Sections of pipelines between shut-off valves and compressors, or shut-off valves and positive displacement pumps, shall be equipped with safety relief valves or bypasses set to discharge at a pressure not less than 240 psig and not over 400 psig.
58 Each safety relief device shall be permanently marked or labelled by the manufacturer with the following information:
(a) start to discharge pressure in psig;
(b) full-open rate of discharge in c.f.m. of air at 60°F and 14.7 psia;
(c) letters “NH3” or “A.A.” to indicate its suitability for use in anhydrous ammonia service;
(d) manufacturer’s name or symbol;
(e) year of manufacture; and
(f) A.S.M.E. or Compressed Gas Association, or Underwriters’ Laboratories symbol.
PART VILoading and Unloading
59 (1) The tank car, during loading or unloading operations, shall be protected on the connected end or ends of the siding by a sign of metal or other suitable material 12 inches by 15 inches in size and reading “STOP — TANK CAR CONNECTED”. The word “STOP” shall be in letters at least four inches high and the other words in letters at least two inches high and the letters shall be white on a blue background.
(2) The “STOP” sign shall be placed on the tank car or on the loading or unloading track in a manner that will ensure it is always visible to the crew of an engine on the same track.
60 (1) At least one experienced operator supplied by the consignor or the consignee, as the case may be, shall supervise the loading or unloading operations, and during the absence of this operator from the installation site, loading or unloading shall be discontinued.
(2) During loading or unloading operations, tank car hand brakes shall be kept applied and the wheels at both ends of the tank car shall be blocked.
(3) Tank cars shall be disconnected from pipelines immediately after the completion of loading or unloading operations.
(4) Loading or unloading operations shall be carried out only during the hours of daylight unless fixed permanent electric lighting is provided in accordance with section 66.
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