Safety always comes first in industry, whether guarding against accidents, food contamination, or fire, chemical, or explosion hazards.
This last is covered by the EU’s ATEX directive, and as its declarations were updated in December 2018 to reflect the latest changes in standards, I thought I’d use this as an opportunity to look at the factors involved in explosion prevention.
The ATEX directive
ATEX stands for ATmosphere Explosive, and is the name of a European directive dealing with explosion hazards under atmospheric conditions. The aim of the directive is to create a safe environment in which explosion hazards are reduced and prevented.
The ATEX directive is applicable to an electric device as a whole. Since an individual part of a conveyor, e.g. the belt, is not an electric device, it cannot be ATEX certified by itself. It’s the conveyor as a whole that will (or will not) comply with the ATEX directive. But the belt can make all the difference in deciding whether the conveyor complies or not.
Risk of explosion
Explosive gas or dust can be created during a production process or transport. Transporting starch or flour, bottling alcohol, and manufacturing fireworks or ammunition are all possible explosion risks. In such environments, it’s essential to avoid high temperatures or sparks created by static discharge. These are potential dangers in a dry environment, for example, if a conveyor has been incorrectly installed and has a loose belt.
The risks of explosion vary in each environment. The environments can be divided into various zones, as shown in the table below:
|Zone||Duration of the occurrence of an explosive atmosphere||Equipment category|
|Gases, vapors, mists||0||continuously, for a long period, frequently||1G|
|2||rarely and for a short period||3G|
|Dusts||20||continuously, for a long period, frequently||1D|
|22||rarely and for a short period||3D|
Habasit conveyor belts with a Declaration of Conformity
In order to make our conveyor belts suitable for an explosive environment, we provide them with conductive wires. This prevents static charge of the belt and so avoids the creation of sparks.
The following Habasit conveyor belts have been extensively tested and come with an official Declaration of Conformity stating that they can be used in ATEX zones 1, 2, 20, 21 and 22:
There are several conditions that must be observed, such as a maximum speed of 5 m/s and the requirement that the belts must have been correctly installed. This is important because incorrect installation can cause slippage that could generate a static charge.
The updates to the ATEX directive in December 2018 do not include any technical changes to the belts or the requirements they must meet. However, several references to parts of the directive and standards of health and safety have changed, and the product marking describing the conditions under which the product can be used have been adjusted.
If you are choosing a conveyor belt for a potentially hazardous environment, contact me for help with finding the best belt for your needs. Habasit takes safety very seriously, and we’ve done our homework to make sure we can give you a belt that’s efficient, reliable and safe.