Classification of hazardous locations

Classification of hazardous locations   

Dangerous places are those places where there is a risk of fires and explosions due to the presence of volatile gases or vapors, liquids, volatile, combustible dust, fibers or burning volatile s (electrical appliances can be a source of ignition and take into account within the hazardous areas)

Hazardous areas are classified into three categories according to their type, condition and nature:

Hazardous areas according to the type (the type of hazardous material)

The first type of places

There are three types of dangerous places.

 The first type, which arises from the presence of gases or fumes when burning these elements exist in the atmosphere, the possibility of explosion exists and which can ignite if Egypt provides an electrical or other known sources of ignition.

 Typical of the places that fall under this category include:

 oil refineries and storage and distribution of gasoline§

 steam washing stations, where the rising vapors of cleaning fluids§

 places finishes using spray§

 aircraft hangars and refueling services.§

 supply of gas plants and operations involving storage and handling of petroleum gas and liquefied natural gas§

 all of these dangerous places under the first category require special equipment for prevention.§

The second type of places:

Places where there are combustible dusts (powders suspended matter in the air as possible to result in a powerful explosion such as that caused by oil refineries)

Typical of the places that fall under this category include:

 grain elevators§

 food floors Mills§

 factories that use or store magnesium or aluminum powder§

 plastic manufacturers, medicine and the work of the fire§

 producers of flour and sweets§

 mills, sugar mills and coca§

 cooling plants and places to deal with and the production of carbon.§

The third type of places:

Places where fiber or volatile atoms according to the type of material that is being carried, stored or manufactured. Fibers or particles may not be volatile in the air but can be grouped on and around the surfaces of materials, lighting, heat and spark one of the hot material can be ignited.

Typical of the places that fall under this category include:

 mills, cotton cloth and collect§

 seed cotton mills, processing plants flax seed§

 factories that refines and cut timber and sawdust produced by atoms and volatile§

Hazardous areas according to the circumstances (the case of hazardous materials)

 There are different types of hazardous materials according to the different circumstances that exist below it. And that in order to simplify understanding can be divided into two sections:

Section I: material under normal circumstances

 Section II: Materials under unusual circumstances

In normal circumstances can be expected the presence of accidents in the production processes or in the daily repetition of repairs and maintenance

When the unexpected and hazardous materials exist within closed containers or closed system and is to appear only through the accidental breaches or errors in the operations, the unusual this case is called up / unusual

The three previous types of hazardous locations can be broken down also to the section or two

 A good example for the possibility of this division that we put under the first section, I kind of dangerous places will be open spaces close to the means / equipment loading and open or close valves in oil refineries

 Because of hazardous materials will be available through the natural processes of the plant.

 Tanks and containers storing petroleum liquids burning inside enclosed storage rooms do not allow escalation of inherently hazardous fumes into the atmosphere, but if there was a leak in one of these reservoirs then we will move to the second section the unusual, which can be taxonomic within the first section of the second type classification of hazardous locations

Thus, the same method can cover the three types of hazardous locations by dividing each into two first cases and in normal circumstances and when the second or turn out to be unusual

Hazardous areas according to the nature of hazardous materials

Substances classified in the groups (A, B, C, D)

Gases and vapors previously classified under the first type of dangerous places split into four groups (A, B, C, D)

This has been done Altdzoh in groups according to the degree and all flammable material from the pressure of the blast and other characteristics of ignition

Group A: This collection contains only acetylene gas, the intensity of gravity (which has a very high pressure of the blast)

Group B: contains the hydrogen gas and a number of other gases with similar properties has

Group C and D: contains at most of the group, which included the first type of classification of hazardous locations

 And especially the fourth group includes most of the burning material, such as butane, gasoline and natural gas.

Substances classified in the groups (E, F, G)

These groups were classified according to the degree of ignition and conductivity (electrical conductivity) for hazardous materials. They often include items previously classified under the second type of hazardous areas - dusty places, especially metal dust of the high degree of electrical conductivity (conductivity)

Group E dust include metals (aluminum and magnesium dust and other types of dust with similar properties)

Group F and the presence of carbon in the atmosphere, coal dust

Group G dust grains, flour, cocoa and similar materials