ATEX Category 2D and 2GD Industrial Vacuum Systems

What is an ATEX Vacuum System?

ATEX is an abbreviation/acronym of “ATmosphères EXplosibles” (Explosive Atmospheres).  An ATEX vacuum system is a vacuum system which is specifically designed, built and certified for use in Potentially Explosive Atmospheres also known as Hazardous Areas.  Hazardous Areas are working areas endangered by the presence of flammable gases, vapors, mists or dusts that have the potential to be explosive in presence of oxygen and a source of ignition.

ATEX vacuum systems are commonly referred to as explosion proof vacuum systems and dust ignition proof vacuum systems.

Potentially Explosive Atmospheres can be created in refineries, chemical factories, paint shops, flour mills, process manufacturing sites and where work activities create or release flammable gases or vapors.

To prevent explosions from occurring in these sensitive working environments, the European community has adopted two directives concerning Potentially Explosive Atmospheres called ATEX directives.  These two directives outline the responsibilities of manufacturers and customers concerning the use of equipment in potentially explosive atmospheres

The Customers' responsibility

The responsibility of customers is to assign zones to their working areas, as defined in the Directive 99/92/EC also known as ATEX 137, ATEX 153 or the ATEX "Worker safety Directive", and to determine the substances that the EX. proof vacuum system will recover.

Tiger-Vac's responsibility as a manufacturer of Certified ATEX Vacuum Systems

The responsibility of Tiger-Vac is to manufacture ATEX industrial vacuum systems that meet the requirements for the categories defined in the Directive 2014/34/EU, (also known as ATEX 94/9/EC, ATEX 95, ATEX 114 or ATEX 100a or the ATEX "Equipment" Directive), and to inform customers concerning the material the EX. proof vacuum system can recover.

Compliance with ATEX directives

As per ATEX Directive 2014/34/EU all equipment (including vacuum systems) and protective systems which may be used in areas endangered by potentially explosive atmospheres (created by the presence of flammable gases, vapors, mists or dusts) need to be compliant to ATEX standards, certified and marked. As of June 30, 2006, all existing equipment and protective systems that were installed and are not compliant need be changed or modified to become compliant.

How to choose the right ATEX Vacuum System for your application?

To choose the right ATEX Vacuum System for your application, you will have to identify what kind of material the vacuum system will have to recover and determine the classification of the area where the vacuum system will be used.

Identifying the material to be recovered

The first step in selecting the correct ATEX Vacuum System for your application is to identify the material to be recovered.   “Dry only” vacuum systems that are designed to recover dust or dry material only.   “Wet and dry” vacuum systems that are designed to recover dry material or liquids.  Vacuum systems are not designed to recover mud (mixture of liquid and soil). Mud would obstruct filters and decrease the performance of the vacuum system.

Flammable materials can be gaseous, liquid or solid.  To work in potentially explosive atmospheres where flammable materials are present Tiger-Vac always suggest an explosion proof vacuum system designed in conformance with ATEX 2014/34/EU directive.

Tiger-Vac has developed ATEX industrial vacuum systems to be able to recover specific materials such as flammable liquids (such as jet fuel and solvents) and combustible and conductive dust (such as metal powder and gun powder).

Zoning for working areas as defined in the Directive 99/92/EC

Zoning for gas

Zone 0: A place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas, vapor or mist is present continuously or for long periods or frequently.

Zone 1: A place in which an explosive atmosphere consisting of a mixture with air or flammable substances in the form of gas, vapor or mist is likely to occur in normal operation occasionally.

Zone 2: A place in which an explosive atmosphere consisting of a mixture with air of flammable substances in the form of gas, vapor or mist is not likely to occur in normal operation but, if it does occur, will persist for a short period only.

Zoning for dust

Zone 20: A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is present continuously, or for prolonged periods or frequently.

Zone 21: A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is likely to occur in normal operation occasionally.

Zone 22: A place in which an explosive atmosphere in the form of a cloud of combustible dust in air is not likely to occur in normal operation but, if it does occur, will persist for a short period only.

Example of zonings

Categories for ATEX Vacuum Systems as defined 2014/34/EU.

Category 1: Equipment category 1 comprises equipment designed to be capable of functioning in conformity with the operational parameters established by the manufacturer and ensuring a very high level of protection.

Equipment in this category is intended for use in areas in which explosive atmospheres caused by mixtures of air and gases, vapors or mists or by air/dust mixtures are present continuously, for prolonged periods or frequently.

Equipment in this category must ensure the requisite level of protection, even in the event of rare incidents relating to equipment, and is characterized by means of protection such that:

• either, in the event of failure of one means of protection, at least an independent second means provides the requisite level of protection,
• or the requisite level of protection is assured in the event of two faults occurring independently of each other

Category 2: Equipment category 2 comprises equipment designed to be capable of functioning in conformity with the operational parameters established by the manufacturer and of ensuring a high level of protection.

Equipment in this category is intended for use in areas in which explosive atmospheres caused by gases, vapors, mists or air/dust mixtures are likely to occur occasionally.

The means of protection relating to equipment in this category ensure the requisite level of protection, even in the event of frequently occurring disturbances or equipment faults which must be considered.

Category 3: Equipment category 3 comprises equipment designed to be capable of functioning in conformity with the operating parameters established by the manufacturer and ensuring a normal level of protection.

Equipment in this category is intended for use in areas in which explosive atmospheres caused by gases, vapors, mists, or air/dust mixtures are unlikely to occur or, if they do occur, are likely to do so only infrequently and for a short period only.

Equipment in this category ensures the requisite level of protection during normal operation.

Gas Groups

IIA          Acetone, Benzene, Butane, Propane, Hexane, Paint Solvent, Natural gas

IIB           Cyclopropane, Ethyl ether, Ethylene

IIC           Hydrogen, Acetylene

Dust Groups

IIIA         Combustible flyings

IIIB         Non-conductive combustible dust, specific electrical resistance > 10³ Ω

IIIC         Conductive combustible dust, specific electrical resistance < 10³ Ω