From mines to each and every pore of the industry
The first negative experiences with gases and explosions came from the mines, and the risk spread to almost all areas of the economy during the industrial revolution. Flammable gases, dust and vapours mixed with air are the companions of today’s modern production technologies. Gas detectors are designed to detect the release of toxic gases or vapours; they also detect oxygen deficiency and monitor the presence of flammable gases and vapours. It is important to realize that even a small concentration of toxic gases is harmful to health, while a mixture of air and flammable and explosive gases may have catastrophic consequences for people and the environment.
The detection of concentrations below the lower explosion limit is crucial
There’s demand in the industry for efficient secondary protection against explosions. This means that potential ignition sources are rendered ineffective, or that explosion is prevented from reaching a neighbouring explosive substance using a protective covering. However primary protection against explosions is much more efficient. Different methods of detecting explosive gases are used to detect their concentration before they reach the lower explosion limit, in the first phases of leaking (timely localization of potential explosions). In order to prevent the formation of explosive concentrations in a room, an intelligent explosive gas detection system shuts down all devices (such as the gas inlet, electrical installations and devices) and turns on the ventilation system. This is also useful in underground garages, heat and gas stations, boiler rooms…
Proper selection and installation are important
Depending on the type of gas there are different detectors on the market that are designed to detect toxic, explosive or flammable gases.
For proper installation of gas detectors it is very important to know the relative density of the gas in relation to air. Lighter gases rise from the location of the leak like smoke (the rarer the gas the quicker it rises) and mix with air as they spread. The mixture accumulates and spreads below the ceiling like a cloud. Heavier gases fall from the location of the leak like a waterfall (the thicker the gas the faster it falls). The mixture spreads on the ground in a layer, filing each and every dent. Detectors for heavier gases are mounted approximately 20 cm above the ground; for lighter gases, they are mounted below the ceiling. It makes sense to mount detectors for gases which affect humans at head height. Air currents, the shape of rooms, the layout of working spaces etc. have to be taken into account during installation.
The most common cause of death from accidental poisoning is carbon monoxide or the “silent killer”, as it is also known. Carbon monoxide is invisible, colourless and odourless. It is a product of incomplete combustion of gasoline, wood, coal, natural gas, propane, oil and methane – and it cannot be detected without a proper detector.
Types of hazardous gases