Flammable gas alarm

Given that the question raised by the original poster is too general, I shall only provide the following suggestions for reference: The installation of gas detection alarms should be carried out in accordance with the \"Design Code for Detection and Alarm of Flammable and Toxic Gases in Petrochemical Enterprises\" 3.0.1. In Area 2 and Additional Area 2 of process units and storage and transportation facilities that produce or use flammable gases (including tank areas for Class A gases and liquefied hydrocarbons, Class B liquids, as well as loading/unloading facilities and filling stations, etc., the same below), gas detection alarms must be installed in compliance with this code. Toxic gas detection and alarm devices shall be installed in the areas of process units and storage and transportation facilities that produce or use toxic gases, in accordance with these specifications. 1 When there are combustible gases or gases containing toxic substances, and in the event of a leak the concentration of the combustible gases may reach 25% LEL while the concentration of toxic gases does not reach their maximum allowable level, a combustible gas detection and alarm device should be installed ； 2 When toxic gases or gases containing flammable gases are present, and in the event of a leak the concentration of toxic gases may reach the maximum allowable level, but the concentration of flammable gases does not reach 25% LEL, a toxic gas detection alarm should be installed ； 3 Being both a flammable gas and a toxic gas, only a toxic gas detection alarm is installed ； 4 In areas where flammable gases and toxic gases are present simultaneously, detectors and alarms for both flammable gases and toxic gases should be installed. The installation of detection and alarm devices shall comply with Article 3.0.7 of the \"Design Code for Detection and Alarm of Flammable and Toxic Gases in Petrochemical Enterprises\": detectors should be placed on the upwind side of the wind direction corresponding to the lowest frequency of release of flammable or toxic gases. 3.0.8 The effective coverage radius in the horizontal plane of a combustible gas detector should be 7.5 m indoors ； It should be 15m outdoors. One detector can be installed within the effective coverage area. The distance between the toxic gas detector and the source of release should not exceed 2 meters in outdoor areas, and should not exceed 1 meter in indoor areas. 3.0.9 In the areas where gas detectors for flammable gases or toxic gases are required according to the provisions of this specification, fixed-type detectors are preferred; when it is not possible to use fixed-type detectors, portable detectors should be installed. 3.0.10 The combustible gas and toxic gas detection and alarm systems should be relatively independent instrumentation systems. The determination of detection points shall be in accordance with the \"Design Code for Detection and Alarm of Flammable and Toxic Gases in Petrochemical Enterprises\", section 4.1 Process Units, 4.1.1. Detectors shall be installed at the release sources of the following flammable and toxic gases: 1) Dynamic seals of Class A gases or toxic gas compressors, liquefied hydrocarbon pumps, Class B A or group-mounted Class A B liquid pumps, and liquid pumps that can emit toxic gases ； 2 Sampling ports that may leak Class A gases, toxic gases, liquefied hydrocarbons, or Class B liquids as well as liquids that can emit toxic gases during abnormal operation, and discharge (water) ports that may carry liquefied hydrocarbons, Class B liquids, and liquids that can emit toxic gases during improper operation ； 3 Equipment or pipe flanges, valve assemblies that may leak Class A gases, toxic gases, or liquefied hydrocarbons during abnormal operation. 4.1.2 In equipment areas where the combustible gas release sources specified in Article 4.1.1 are located in an open or semi-open environment, when the detection point is situated upwind of the direction from which the gas is released with the highest frequency, the distance between the combustible gas detection point and the release source should not exceed 15 m, while the distance between the toxic gas detection point and the release source should not exceed 2 m ； When the detection point is located downwind of the wind direction corresponding to the lowest frequency of the release source, the distance between the combustible gas detection point and the release source should not exceed 5 m, while the distance between the toxic gas detection point and the release source should be less than 1 m. 4.1.3 When the combustible gas release sources specified in Article 4.1.1 are located in enclosed or semi-enclosed buildings, a detector can be installed every 15 meters, and the distance between each detector and any release source shall not exceed 7.5 meters. The toxic gas detector should not be more than 1 m away from the source of release. 4.1.4 When equipment of different fire hazard categories is installed in enclosed or semi-enclosed buildings, detectors shall be installed within 7.5 m of the combustible gas release sources specified in Article 4.1.1. 4.1.5 When the source of flammable gases lighter than air specified in Article 4.1.1 is located within a closed or semi-closed building, detectors shall be installed above the source, as well as at the highest points within the building where flammable gases are likely to accumulate. This post was last edited by lyhh9024 on 2009-4-18 01:24.]

It’s useful; an alarm is triggered when the leakage of combustible gases reaches a certain level.

Gas detectors are useful in most cases in areas where hazardous chemicals are stored, as well as in locations where leaks frequently occur, such as the mechanical seals of liquid ammonia pumps.

It is certainly useful, but it depends on the location. In some places, its installation will result in continuous alarms being issued; this is the case in the compression sections of ammonia synthesis plants, which are special situations. Suggested settings

It’s very effective; since our company installed it, we have avoided several leaks of combustible gases.

Flammable gas detectors cannot prevent leaks, but they can detect them early

It is installed on the device, and it stops working once the concentration becomes too high.

Our unit passes the annual inspections every time, but there is no alarm for any product leakage right next to the explosion detector; it’s really frustrating

Reply to 2# lyhh9024: May I ask, what is its working principle? ? ? I know it’s used to measure the concentration of volatile flammable gases or liquids, but when does it trigger an alarm? ? ? Should it keep sending alerts as soon as it is detected, or should an alert be sent only when the **lower limit is reached (and if that’s the case, isn’t it too late)?

It’s not just about installation; regular maintenance over time is also necessary. It needs to be verified regularly!