Tell me more about safety concerns regarding ammonia compressors in a boil-off gas system

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Division 2 AO 3-2019 Oregon Administrative Rules Oregon Occupational Safety and Health Division - (B) Positive displacement pumps shall have, installed off the discharged port, a constant differential relief valve discharging into the suction port of the pump through a line of sufficient size to carry the full capacity of the pump at relief valve setting, which setting and installation shall be according to the pump manufacturer's recommendations. - (C) On the discharge side of the pump, before the relief valve line, there shall be installed a pressure gage graduated from 0 to 400 p.s.i. - (D) Plant piping shall contain shutoff valves located as close as practical to pump connections. - (vi) Compressors used for transferring or refrigerating ammonia shall be recommended for ammonia service by the manufacturer. - (A) Compressors shall be designed for at least 250 p.s.i.g. working pressure. - (B) Plant piping shall contain shutoff valves located as close as practical to compressor connections. - (C) A relief valve large enough to discharge the full capacity of the compressor shall be connected to the discharge before any shutoff valve. - (D) Compressors shall have pressure gages at suction and discharge graduated to at least one and one-half times the maximum pressure that can be developed. - (E) Adequate means, such as drainable liquid trap, shall be provided on the compressor suction to minimize the entry of liquid into the compressor. - (vii) Loading and unloading systems shall be protected by suitable devices to prevent emptying of the storage container or the container being loaded or unloaded in the event of severance of the hose. Backflow check valves or properly sized excess flow valves shall be installed where necessary to provide such protection. In the event that such valves are not practical, remotely operated shutoff valves may be installed. - (13) Tank car unloading points and operations. - (i) Provisions for unloading tank cars shall conform to the …

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Division 2 AO 3-2019 Oregon Administrative Rules Oregon Occupational Safety and Health Division - (iv) Safety-relief valves shall be so arranged that the possibility of tampering will be minimized. If the pressure setting adjustment is external, the relief valves shall be provided with means for sealing the adjustment. - (v) Shutoff valves shall not be installed between the safety-relief valves and the container; except, that a shutoff valve may be used where the arrangement of this valve is such as always to afford full required capacity flow through the relief valves. - (vi) Safety-relief valves shall have direct communication with the vapor space of the container. - (vii) Each container safety-relief valve used with systems covered by paragraphs (c), (f), (g), and (h) of this section shall be plainly and permanently marked with the symbol 'NH3' or 'AA;' with the pressure in pounds-per-square-inch gage at which the valve is set to start-todischarge; with the actual rate of discharge of the valve at its full open position in cubic feet per minute of air at 60 degrees F. and atmospheric pressure; and with the manufacturer's name and catalog number. - Example: 'NH3 250 4050 Air' indicates that the valve is suitable for use on an anhydrous ammonia container, is set to start-to-discharge at a pressure of 250 p.s.i.g., and that its rate of discharge at full open position (Subdivisions (ii) and (iii) of this subparagraph) is 4,050 cubic feet per minute of air. - (viii) The flow capacity of the relief valve shall not be restricted by any connection to it on either the upstream or downstream side. - (ix) A hydrostatic relief valve shall be installed between each pair of valves in the liquid ammonia piping or hose where liquid may be trapped so as to relieve into the atmosphere at a safe location. ## (10) General. - (i) (Reserved) - (ii) Stationary storage installations must have at least two suitable gas masks in readily-accessible locations. Full-face masks with amm…

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Division 2 AO 3-2019 Oregon Administrative Rules Oregon Occupational Safety and Health Division - (16) Electrical equipment and wiring. - (i) Electrical equipment and wiring for use in ammonia installations shall be general purpose or weather resistant as appropriate. - (ii) Electrical systems shall be installed and maintained in accordance with Subpart S of this part. - (c) Systems utilizing stationary, nonrefrigerated storage containers. This paragraph applies to stationary, nonrefrigerated storage installations utilizing containers other than those covered in paragraph (e) of this section. Paragraph (b) of this section applies to this paragraph unless otherwise noted. - (1) Design pressure and construction of containers. The minimum design pressure for nonrefrigerated containers shall be 250 p.s.i.g. - (2) Container valves and accessories, filling and discharge connections. - (i) Each filling connection shall be provided with combination back-pressure check valve and excess-flow valve; one double or two single backpressure check valves; or a positive shutoff valve in conjunction with either an internal back-pressure check valve or an internal excess flow valve. - (ii) All liquid and vapor connections to containers except filling pipes, safety relief connections, and liquid-level gaging and pressure gage connections provided with orifices not larger than No. 54 drill size as required in paragraphs (b)(6)(iv) and (v) of this section shall be equipped with excessflow valves. - (iii) Each storage container shall be provided with a pressure gage graduated from 0 to 400 p.s.i. Gages shall be designated for use in ammonia service. - (iv) All containers shall be equipped with vapor return valves. - (3) Safety-relief devices. - (i) Every container shall be provided with one or more safety-relief valves of the spring-loaded or equivalent type in accordance with paragraph (b)(9) of this section.

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Division 2 AO 3-2019 Oregon Administrative Rules Oregon Occupational Safety and Health Division - (ii) An emergency source of power of sufficient capacity to handle the loads listed in paragraphs (d)(8)(i)(A) and (B) of this section shall be provided unless facilities are available to safely dispose of vented vapors while the refrigeration system is not operating. - (11) Automatic control equipment. - (i) The refrigeration system shall be arranged with suitable controls to govern the compressor operation in accordance with the load as evidenced by the pressure in the container(s). - (ii) An emergency alarm system shall be installed to function in the event the pressure in the container(s) rises to the maximum allowable operating pressure. - (iii) An emergency alarm and shutoff shall be located in the condenser system to respond to excess discharge pressure caused by failure of the cooling medium. - (iv) All automatic controls shall be installed in a manner to preclude operation of alternate compressors unless the controls will function with the alternate compressors. - (12) Separators for compressors. - (i) An entrainment separator of suitable size and design pressure shall be installed in the compressor suction line of lubricated compression. The separator shall be equipped with a drain and gaging device. - (ii) (Reserved) - (13) Condensers. The condenser system may be cooled by air or water or both. The condenser shall be designed for at least 250 p.s.i.g. Provision shall be made for purging noncondensibles either manually or automatically. - (14) Receiver and liquid drain. A receiver shall be provided with a liquid-level control to discharge the liquid ammonia to storage. The receiver shall be designed for at least 250 p.s.i.g. and be equipped with the necessary connections, safety valves, and gaging device. - (15) Insulation. Refrigerated containers and pipelines which are insulated shall be covered with a material of suitable quality and thickness for the t…

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Oregon Occupational Safety and Health Division Oregon Administrative Rules AO 3-2019 Division 2 - (i) Consideration shall be given to the physiological effects of ammonia as well as to adjacent fire hazards in selecting the location for a storage container. Containers shall be located outside of buildings or in buildings or sections thereof especially provided for this purpose. - (ii) Permanent storage containers shall be located at least 50 feet from a dug well or other sources of potable water supply, unless the container is a part of a water-treatment installation. - (iii) (Reserved) - (iv) (Reserved) - (v) Storage areas shall be kept free of readily ignitible materials such as waste, weeds, and long dry grass. - (6) Container appurtenances. - (i) All appurtenances shall be designed for not less than the maximum working pressure of that portion of the system on which they are installed. All appurtenances shall be fabricated from materials proved suitable for anhydrous ammonia service. - (ii) All connections to containers except safety relief devices, gaging devices, or those fitted with No. 54 drill-size orifice shall have shutoff valves located as close to the container as practicable. - (iii) Excess flow valves where required by these standards shall close automatically at the rated flows of vapor or liquid as specified by the manufacturer. The connections and line including valves and fittings being protected by an excess flow valve shall have a greater capacity than the rated flow of the excess flow valve so that the valve will close in case of failure of the line or fittings. - (iv) Liquid-level gaging devices that require bleeding of the product to the atmosphere and which are so constructed that outward flow will not exceed that passed by a No. 54 drill-size opening need not be equipped with excess flow valves. - (v) Openings from the container or through fittings attached directly on the container to which pressure gage connections are made need not b…

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Division 2 AO 3-2019 Oregon Administrative Rules Oregon Occupational Safety and Health Division - (vi) Excess flow and back pressure check valves where required by the standards in this section shall be located inside of the container or at a point outside as close as practicable to where the line enters the container. In the latter case installation shall be made in such manner that any undue strain beyond the excess flow or back pressure check valve will not cause breakage between the container and the valve. - (vii) Excess flow valves shall be designed with a bypass, not to exceed a No. 60 drill-size opening to allow equalization of pressures. - (viii) All excess flow valves shall be plainly and permanently marked with the name or trademark of the manufacturer, the catalog number, and the rated capacity. - (7) Piping, tubing, and fittings. - (i) All piping, tubing, and fittings shall be made of material suitable for anhydrous ammonia service. - (ii) All piping, tubing, and fittings shall be designed for a pressure not less than the maximum pressure to which they may be subjected in service. - (iii) All refrigerated piping shall conform to the Refrigeration Piping Code, American National Standards Institute, B31.5-1966 with addenda B31.1a1968, which is incorporated by reference as specified in 1910.6, as it applies to ammonia. - (iv) Piping used on nonrefrigerated systems shall be at least American Society for Testing and Materials (ASTM) A-53-69 Grade B Electric Resistance Welded and Electric Flash Welded Pipe, which is incorporated by reference as specified in 1910.6, or equal. Such pipe shall be at least schedule 40 when joints are welded, or welded and flanged. Such pipe shall be at least schedule 80 when joints are threaded. Threaded connections shall not be back-welded. Brass, copper, or galvanized steel pipe shall not be used. - (v) Tubing made of brass, copper, or other material subject to attack by ammonia shall not be used. - (vi) Cast iron fittings …

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Oregon Occupational Safety and Health Division Oregon Administrative Rules AO 3-2019 Division 2 - (i) The content of tank motor vehicle containers shall be determined by weight, by a suitable liquid-level gaging device, or other approved methods. If the content of a container is to be determined by liquid-level measurement, the container shall have a thermometer well so that the internal liquid temperature can be easily determined. This volume when converted to weight shall not exceed the filling density specified by the DOT. - (ii) Any pump, except a constant speed centrifugal pump, shall be equipped with a suitable pressure actuated bypass valve permitting flow from discharge to suction when the discharge pressure rises above a predetermined point. Pump discharge shall also be equipped with a spring-loaded safety relief valve set at a pressure not more than 135 percent of the setting of the bypass valve or more than 400 p.s.i.g., whichever is larger. - (iii) Compressors shall be equipped with manually operated shutoff valves on both suction and discharge connections. Pressure gages of bourdon-tube type shall be installed on the suction and discharge of the compressor before the shutoff valves. The compressor shall not be operated if either pressure gage is removed or is inoperative. A spring-loaded, safety-relief valve capable of discharging to atmosphere the full flow of gas from the compressor at a pressure not exceeding 300 p.s.i.g. shall be connected between the compressor discharge and the discharge shutoff valve. - (iv) Valve functions shall be clearly and legibly identified by metal tags or nameplates permanently affixed to each valve. - (7) (Reserved) - (8) (Reserved) - (9) Chock blocks. At least two chock blocks shall be provided. These blocks shall be placed to prevent rolling of the vehicle whenever it is parked during loading and unloading operations. - (10) Portable tank containers (skid tanks). Where portable tank containers are used for farm sto…

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## (COMPRESSED GASES & AIR) ## Equipment Procedures and Requirements ## §1910.430 Equipment. ## (a) General. - (1) All employers shall comply with the following requirements, unless otherwise specified. - (2) Each equipment modification, repair, test, calibration or maintenance service shall be recorded by means of a tagging or logging system, and include the date and nature of work performed, and the name or initials of the person performing the work. ## [redacted phone] Air Supply Systems (Compressed Gases and Air). - (1) For purposes of this standard, air supply systems shall include: - (a) Air supplied directly to a diver; - (b) Compressed systems used to fill air cylinders (tanks); - (c) Compressed air cylinders (tanks); and - (d) Compressed oxygen cylinder. - (e) For additional requirements for compressed gas cylinders, see OAR Division 2/H, 1910.101, Compressed Gases; Division 2/I, 1910.134(d), Respiratory Protection; and 30 CFR 11, Respiratory Protective Devices. ## (b) Air compressor system. - (1) Compressors used to supply air to the diver shall be equipped with a volume tank with a check valve on the inlet side, a pressure gauge, a relief valve, and a drain valve. - (2) Air compressor intakes shall be located away from areas containing exhaust or other contaminants. - (3) Respirable air supplied to a diver shall not contain: - (i) A level of carbon monoxide (CO) greater than 20 p/m; - (ii) A level of carbon dioxide (CO2) greater than 1,000 p/m; - (iii) A level of oil mist greater than 5 milligrams per cubic meter; or