Continuous monitoring of carbon monoxide and nitrogen dioxide in welding shops
ระบบตรวจจับก๊าซพิษในโรงเชื่อม
การเชื่อมโลหะเป็นกระบวนการที่ก่อให้เกิดก๊าซพิษหลายชนิด เช่น คาร์บอนมอนอกไซด์ ไนโตรเจนไดออกไซด์ โอโซน ไฮโดรเจนคลอไรด์ คาร์บอนไดออกไซด์ ไนตริกออกไซด์ และฟลูออไรด์ ก๊าซพิษเหล่านี้เป็นอันตรายต่อสุขภาพของคนงาน เช่น ทำให้ขาดอากาศหายใจ ไฟไหม้ ระเบิด และเป็นพิษ
ระบบตรวจจับก๊าซพิษ
เพื่อป้องกันอันตรายจากก๊าซพิษ ควรติดตั้งระบบตรวจจับก๊าซคาร์บอนมอนอกไซด์และไนโตรเจนไดออกไซด์ในโรงงานเชื่อม
- เครื่องตรวจจับก๊าซ cGas-SC Self Contained Controller: ตรวจจับก๊าซคาร์บอนมอนอกไซด์และไนโตรเจนไดออกไซด์
- ติดตั้งเครื่องตรวจจับ ในบริเวณที่คนงานทำงาน
- ระบบเตือนภัย เมื่อตรวจพบก๊าซเกินค่าปกติ
Welding joins material together by melting metal and adding a filler to form a strong joint. There are over 70 different types of welding processes, all which produce a variety of hazardous gases. The gas or gases generated and their concentrations depend on the process used and the gas formation mechanisms. Common gases produced are carbon monoxide, nitrogen dioxide, ozone, hydrogen chloride, carbon dioxide, nitric oxide and other gaseous fluorides. The health hazards from welding gases are asphyxiation (lack of oxygen), fire, explosion and toxicity.A well designed and maintained ventilation system is required to remove the air contaminants from the welder’s breathing zone. The installation of a fixed gas detection system to continuously monitor the levels hazardous gases help to protect welders and workers from exposure and risks to their health, providing a safer working environment. For a common indoor welding environment, Critical Environment Technologies’ cGas-SC Self Contained Controller with one internal electrochemical CO sensor and one internal electrochemical NO2 sensor offers the features and functionality to ensure a safe breathing environment
Welding activities occur in many industries and the work environments vary in size, layout and setup. When planning installation and mounting locations for each cGas-SC Self Contained Controller, you must consider the air flow patterns inthe room; entrances to the room, type of ventilation system, number of welding stations and any other sources of active air currents will affect the ability of the sensors to accurately read the gas levels. The cGas-SC, with two internal sensors, one Carbon Monoxide (CO) and one Nitrogen Dioxide (NO2 ), should be mounted close to the welding work stations, in the “breathing zone” which is 1.2 to 1.8 meters (4 to 6 feet) from the floor. This is the height at which most humans breathe and the height at which these gases pool. In poorly ventilated areas, gases can accumulate and displace the oxygen causing an oxygen-deficient environment. The cGas-SC has three gas alarm setpoints, LOW, MID and HIGH and two dry contact relays rated 5A @ 240 VAC. If the ventilation system is inadequate or malfunctions and there is a buildup of hazardous gas, the cGas-SC will detect the increase in the gas level and according to the gas alarm levels, activate its internal buzzer and one or both of its internal relays. Relay one could be configured to actuate exhaust fans to bring the gas level down to an acceptable level and relay two could be used to activate a remote strobe/horn in a secondary location to alert workers. Depending on the type of welding being done, additional hazardous gas monitoring may be required. For example, for Oxy-Acetylene welding, consideration should be given to monitoring combustible gas and Oxygen levels in the room where the cylinders of gas are stored. If there were to be a leak, Acetylene is flammable and explosive and high levels of Oxygen could cause an O2 enriched atmosphere. A cGas-SC Self Contained Controller with an internal Oxygen sensor and a remote ESH-A combustible sensor would provide accurate and continuous monitoring to ensure a safe working environment. The cGas-SC
with the Oxygen sensor should be installed inside the room at breathing level 1.2 to 1.8 m (4 to 6 feet) off the ground and the ESH-A Acetylene sensor should be mounted near the ceiling as Acetylene gas is lighter than air and will concentrate in high places). If the area is classified as a hazardous location, the use of a CXT2 Explosion Proof transmitter, one with an infrared Acetylene sensor and the other with an Oxygen sensor, is recommended. Line voltage and/or analog outputs can be added to the cGas-SC Self Contained Controller basic model if required. The cGas-SC fixed system is fully set up, programmed, calibrated and tested prior to being shipped from the factory. It is ready to install upon arrival and operate following the warm up period
#gasdetection #welding #industrialsafety #occupationalhealth #carbonmonoxide #nitrogenoxide #safetyfirst #healthandsafety #workplace safety
