When do i need ATEX?

The ATEX Directive applies where during normal operation or malfunction of a machine and / or plant explosive atmospheres. Emergencies are not covered. The new Directive (94/9/EC 99/92/EC +) replaces Directives 76/117/EEC and 94/9/EC 82/130/EEG.Richtlijn is intended for the manufacture of the equipment, Directive 99/92 / EC isbedoeld for working in explosive environments (work). The ATEX Directive covers all potential explosive atmospheres which may arise due to gases, vapors, mists or dusts.

Excluded from the ATEX directive are:

Medical environments
Household environments
Non-commercial environments
Public transport

Besides equipment and protective systems intended for use in potentially explosive atmospheres are also things outside this area under the Directive if they are required voorhet safe operation of the equipment.

When there is a potentially explosive atmosphere? If the correct proportion of oxygen, flammable product and possible ignition source is.Voor an ignition source must be also discharges denken.Een atmosphere is explosive from the LEL to UEL.

Of almost all products can be safety data retrieval, herein you will find all the necessary information such as the LEL, UEL, flash point etc. Also the flash point is a very important criterion. We have below then a portion of two safety data sheets printed on very famous products, namely Acetone and Diesel.

Physical and chemical properties of       ACETONE                        DIESEL                         
Physical state at 20 ° C Liquid Liquid
View color Clear, colorless Light yellow
Odor Irritant Characteristic
Boiling 58 ° C 170 ° C
Melting point -95 ° C  
Flashpoint -19 ° C > 56 ° C
Ignition temperature 465 ° C > 250 ° C
Relative vapor density (air = 1) 2.0  
Flammability limit (LEL) 2.3% (v / v) 1% (v / v)
Flammability limit (UEL) 13% (v / v) 6% (v / v)
Relative density (water = 1) 0.8  
Water-soluble Completely soluble No data available


Product LEL           UEL              Flashpoint      Application
Acetone 2.3% 13% -19 ° C Diluent
Diesel 1% 6% 56 ° C Fuel for diesel engines
Gasoline (unleaded Euro 95) 1% 6% - 8% -40 ° C Fuel for petrol engines
Ammoniac 15% 30% Gas Refrigerant for refrigeration
Gas 5% 15.8% Gas Fuel
Hydrogen 4% 75% Gas General Industrial

Definition of "flashpoint"

The lowest temperature at which a liquid fluid, under certain standard conditions so much vapor that is an ontsteekbar vapor / air mixture can be formed. One must take into account in normal atmospheric conditions from a omgevingstemperatuurvan -20 ° C to +40 ° C, 10 ° C math here to reserve one arrives at 50 ° C.In principle, all products from a flash point of 50 ° C or higher as diesel is not explosive dangerous. Of course there are circumstances that still a hazardous explosive atmosphere can be achieved by eg certain production processes (sputtering, etc ...). >

Definition of "LEL" and "UEL"

Lower Explosive Limit (LEL): Concentration of flammable gas, flammable vapors or combustible mist in air below which no explosive atmosphere is formed.

Upper Explosive Limit (UEL): Concentration of flammable gas, flammable vapors or combustible mist in air above which an explosive atmosphere is formed.

If a product has an LEL of 15% or more (such as ammonia) will in no danger Outdoor installations be seeded. Indeed, it is not possible that, in practice, higher concentrations may occur over 15% due to the mixing of the outside air. Consequently, an ammonia plant in the open air outside the ATEX Directive, notwithstanding that it is a gas.


When do i need to comply with the ATEX Directive?

For products with a lower than 15% LEL and a flash point lower than 50 ° C, one can speak of a potentially explosive atmosphere. In this case one falls under the ATEX directive and one is obliged to make a zone classification according to the applicable guidelines and standards. Also, all materials comply with the ATEX Directive.


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