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ENVIRONMENTS AND STANDARDS
Explosive environments (ATEX and HAZLOC standards)
The ATEX standard
What is the ATEX?
The ATEX regulation is a European directive which requires all heads of
organizations to fully understand the risks related to certain explosive
environments. To do this, an evaluation of the risk of explosion in a company
is required in order to identify any locations where explosive environments
could form, and then to put in place the means to avoid explosion.
Oxygen in the air
How do you choose equipment that is adapted for an environment at risk of
explosion?
ATEX environments are subdivided into three zones:
- zones 0, 1 or 2 for gases
- zones 20, 21 or 22 for dust
There are two groups of materials:
- group I: concerns mines (more restrictive)
- group II: concerns all above-ground industries
Source of combustion
(flame, spark, hot spot)
Fuel
(gas or flammable
vapor, dust)
For Group II (above-ground industries), a specifically adapted category of
equipment is associated with each ATEX zone classification.
See more details at www.petzl.com/atex.
Under what conditions can an explosion occur?
The HAZLOC standard
There is a risk of explosion when several elements are present:
- an oxidant: the oxygen in air, for example
- a fuel:
. gas or vapors: hydrocarbons, solvents, varnishes, diluents, gas, alcohol,
dyes, perfumes, chemical products, agents for manufacture of plastics...
. powders and dust: magnesium, aluminum, sulfur, cellulose, cereals, carbon,
wood, milk, resins, sugars, starch, polystyrenes, fertilizer...
- a hot spot or a source of combustion
What is the HAZLOC?
The HAZLOC certification primarily concerns North America.
It aims to control the risks related to explosion in certain environments.
It comprises two elements:
- testing and evaluation of products being used
- inspection of the factory
For example, when filling a grain silo, the concentration of dust is very high.
The environment then is dangerous: a rise in temperature, or even a spark,
can trigger an explosion.
If a risk of explosion is identified in an environment (gas or dust), a safety
requirement is imposed for the use of equipment that is specifically designed
to function without becoming a potential source of combustion.
This equipment offers different types of protection designed to diminish the
risk of explosion.
How do you choose equipment that is adapted for an environment at risk of
explosion?
Hazardous locations are classified in three ways under the HAZLOC standard:
- by type
- by conditions
- by nature of the hazardous substance or material
See more details at www.petzl.com/hazloc.