• Establishment : 1984.04.13
• Establishment : 1984.04.13

Article 6, appendix 2, paragraph 2(4), paragraph 3 (21) (25), appendix 3, paragraph (1)-C, (42) (57), appendix 4, paragraph 1(5), appendix 5, paragraph 1 (8), appendix 6, paragraph 1 (8) of the enforcement decree of high pressure gas safety management act and Article 29, appendix 18 (11) of enforcement decree of the same act

The gas leakage detection system (hereinafter referred to as "detection detector system") detects leakage of combustible gas or toxic gas and indicates the concentration of the Gas Detector and sounds an detector. The function of the gas leakage detector shall be appropriate to the type of gas along with the performance of following issues.

1. A. The detection detector can be automatically activated by the gas concentration (hereinafter referred to as "Detector Concentration") that has already been set by the electrical signal to change the detection element by the contact combustion method, the impending galvanic cell method, and the semiconductor method. In this case, the combustible gas detector shall not be detectored to smoke of cigarette, while toxic gas detector shall not detector to gas such as tobacco smoke, machine washing oil gas, evaporative gas exhaust gas of hydrocarbon, and hydrocarbon gas.
2. B. The detector concentration shall be less than 1/4 of combustible gas and less than the allowable concentration of toxic gas, depending on the installation location of the detection detector and surrounding atmosphere temperature. (However, in case of ammonia, it may be 50 ppm)
3. C. The accuracy of the detector shall be less than + -30% for the combustible gas against the detector concentration set point.
4. D. The time from detection to the release of detector shall be within 30 seconds at the concentration 1.6 times higher than the detector concentration. However, in the case of gas sensors (ammonia, carbon monoxide or similar gases) that take more than 30 seconds in the structure or theoretically of the detection detector system, they shall be within 1 minute.
5. E. Even when the voltage fluctuation of the power supply is + -10%, the detector accuracy shall not be lowered.
6. F. Indicator scale is from zero to explosion limit value for combustible gas. Toxic gases shall be clearly indicated in the range of 0 to 3 times the permissible concentration (150 ppm if ammonia is used indoors) in the range of each scale.
7. G. After sending an detector, in principle, the detector shall sound even if the gas concentration changes in the atmosphere, and the detector shall be stopped when checking or taking measures.

The structure of the detection detector system shall be described in the following subparagraphs.

1. A. Sufficient strength (in particular, the detection element and the transmission circuit shall have durability)
2. B. The parts that come into contact with gas shall be made of corrosion-resistant materials or materials with sufficient corrosion resistance, and the other parts shall be materials with good coating and plating treatment.
3. C. Detection detector of flammable gas (excluding ammonia) shall have explosion proof performance.
4. D. When receiving a detection signal from two or more detection units, the reception circuit shall be able to operate the detector and operate the detector even when other circuits are activated. At the same time, it is also shall be possible to identify the place at where the detector is sounded.
5. E. It shall be convenient to identify that the receiving circuit is in operation.
6. F. The detector shall sound an detector at the same time as the lamp lights or blinks.

The detection detector system shall be installed in accordance with the following

1. A. In the manufacturing facilities (excluding freezing facilities and piping, hereinafter the same shall apply to "A"), the location and number of detectors for detection detectors shall be as follows.
   
   1. For the leakage around places where high pressure gas equipment (except those described in (3) and (4)) installed in the dry matter, such as compressors, valves, reaction equipment and storage tanks, the number shall be calculated at a rate of one or more per 1-m perimeter of the floor area of these facilities where a gas is likely to stay.
   2. Where the high-pressure gas equipment installed outside the building (1) is installed in another high-pressure gas facility, adjacent to a wall or other structure, inside a feed, etc., or if the leaked gas is likely to stay, a ratio shall be calculated at a proportion of one or more to the bottom 20m of the floor of the equipment group in a place where there is a risk of leaked gas staying.
   3. Special reaction facilities (facilities specified in Article 6, appendix 2, paragraph 2-1 of the Enforcement Regulations of the same Act) shall be calculated at a ratio of 1 or more per 10m of the floor circumference in areas where gas leakage is likely to occur.
   4. In a place where gas can easily stay around a manufacturing facility with a source of ignition such as a heating furnace, the number shall be calculated in a ratio for more than once with 20m of circumference on the floor.
   5. One or more inside the instrument room
   6. At least one or more near toxic gas charging connected area
2. B. The location and number of the detection part of the detection detector device in storage facilities, sales facilities or special high-pressure gas use facilities (excluding piping, hereinafter the same shall apply to "B") shall be as follows.
   
   1. For the pressure reducing facilities, storage facilities, sales facilities, and high-pressure gas-using facilities installed in buildings (excluding burner without concern on gas leakage with interlock system installed by pilot burner system) around the place where gas leakage facilities are installed, the number is calculated at a ratio of 1 or more per 10m of the floor circumference of these equipment groups in a place where gas leakage is likely to occur.
   2. If it is installed adjacent to facilities other than those specified in 01 that are installed outside the building or adjacent to a wall structure or in the interior of a pit, the number shall be calculated for more than one with 20m of circumference of the floor with a concern for gas to stay.
3. C. In refrigeration facilities, the location and number of detectors for detection detectors shall be as follows.
   
   1. In the vicinity of a place where a group of facilities (hereinafter referred to as "Equipment Group") such as a compressor, a pump, a condenser, and a receiver belonging to a refrigeration facility installed in a building, the number shall be calculated by one or more ratios with respect to the 10 m perimeter of the bottom surface of the group. However, in the case where the circumference of a facility group installed in a machine room is surrounded by one longitudinal direction and the value obtained by dividing the floor area of the machine room by its area (hereinafter referred to as "facility group area") is 1.8 or more, the number of installations shown in the following table can be used depending on the area of the facility.
       
      

      Equipment group area S(㎡)	0< S≤30	30< S≤70	70< S≤130	130< S≤200	200< S≤290
      Number of installation	2	3	4	5	6

      
      
   2. In case where the electrical equipment in the refrigerator in which the evaporator is installed meets the following criteria, the installation of the detection detector in the refrigerator may be omitted.
      
      1. Cover with a glass cover or wire mesh to protect the light bulb in the refrigerator.
      2. When thermostat is used When the terminal contact is not installed in the refrigerator.
      3. When a protective cover is attached to the outlet in the refrigerator.
      4. An electric motor or other electric machinery in the refrigerator, or a circuit breaker or an overcurrent protection device is installed in the electric line that supplies electric power.
      5. Exceeding the electric motor (rated output 0.2Kw) in the refrigerator), when an overcurrent protection relay is installed.
      6. An electric line that supplies electricity to the refrigerator, where the switch is installed in a position that can be easily operated outdoors.
4. D. The location where the detector of the detection detector system shall be installed in the piping facility is as follows.
   
   1. Part of the emergency shut-off device (in the valve pit where the valve pit is installed)
   2. Portions of piping that are enclosed and installed (including buried) by slew pipes, double layered pipes or protective structures
   3. Portions of the piping structured such that the leaked gas cannot easily stay
5. E. The height at which the detectors are to be installed in the equipment from "A" to "D" shall be determined according to the conditions of the gas specific gravity, the height of the surrounding environment, and the height of the gas facility (refrigerant gas facilities, ambient conditions, structure of refrigerant facilities, etc.).
6. F. The place where the detector sounds or the lamp lights or flashes shall be a place suitable for various measures after the person is resident.

1. (Date of enforcement) This notification shall take effect on the date of notification.
2. (Interim Measures) It shall be in conformity with this standard until June 30, 1985 if the facilities of the approving or reporting party prior to the enforcement of this notification are not to conform to this standard due to the enforcement of this Agreement.