Flexible conduit systems can provide a proven safe and cost effective protection solution for cabling installed in explosive atmospheres. Better safe than sorry is a sensible approach, but make sure that you are not fooled into unnecessarily expensive options warns Tim Creedon, Sales and Marketing Director for Flexicon.
Explosive areas exist where a flammable mixture of gas and air or dust and air exist in large enough quantities and for long enough. If an ignition source exists then there is a real danger of an explosion.
Naturally we all think of the oil and gas industry in such situations, but there are a surprising number of other industries where explosive atmospheres could exist such as in building and construction, transport, marine and defence, food processing, water treatment and power generation to name but a few.
Wherever possible it is important to minimise the risk of explosive mixtures forming and/or prevent the risk of ignition. Where this is impossible or impractical then you need to consider providing protection.
Any electrical installation in such an environment is a potential source of ignition. The degree of protection any equipment requires depends to a large extent on the risk of an explosion occurring in a given area.
To understand the level or protection required, you must understand the nature of flammable mixtures and ignition sources and also how different zones are classified depending on the level of risk.
Gases are classified into 3 groups with group A being the least explosive and group C being the most. Equipment classification is from T1 to T6 according to the maximum allowed temperature resulting from the ignition temperatures of the gas/air mix. It is important to remember that certain fine dusts dispersed in the air can also be explosive.