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ATEX Rated Fans

Don't go unprotected in hazardous environments with a wide range of net zero Innovation award winning

ATEX Fans with Durable Design, Robust Mechanical Construction & Certified Paired Sparkproof Materials

 

Manufactured by leading Global ATEX fan manufacturer Casals Ventilation, and with the shortest lead times in the UK market, our explosion proof range of fans are suitable for hazardous environments within gas zone 1 and 2, and dust zone 21 and 22. Ex h certified construction using responsibly paired materials to avoid ignition, sparks and friction including stainless steel, polypropylene and aluminum. All ATEX rated fans are tested and manufactured to meet the requirements of the ATEX 2014/34/EU to ensure safe and regulated use in the UK market. Complete the enquiry form and let our in-house ATEX experts work with you to find the right ATEX fan product to suit your explosive environment.

ATEX Axial Fans HCX
ATEX Axial Fans
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ATEX Centrifugal Fans
ATEX Centrifugal Fans
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ATEX Fume Fans - Axair Fans
ATEX Polypropylene Fume Fans
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Stainless Steel Axial Fans - Axair Fans
Stainless Steel Fans
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ATEX Roof Fans
ATEX Roof Fans
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Important ATEX Fan Selection Information You Need To Know

ATEX is a constantly evolving topic, which makes it all the more confusing for our customers who aren't regulars in the hazardous area market. ATEX fan selection and ATEX fan placement in the UK market is highly regulated by ATEX Directives and legislation. The below seeks to inform our audience on some of the key principles that affect ATEX fan selections. We encourage you to send your enquiry to us to examine, but also to review the below information so you can understand the implications of your selection on the environment or application you'll be sourcing the fan for. Our team are educated, experienced and trained extensively in ATEX concepts, with all fans manufactured and certified for use in hazardous areas for placement into the UK market.

 

Overview of ATEX and The 2014/34/EU Directive
ATEX, for the uninitiated, is an acronym derived from the French expression ATmosphères EXplosibles and exists for our purposes in the form of a European
- 'product directive' 2014/34/EU previously 94/9/EC (ATEX 100) covering manufacturing standards, and as
- 'workplace directive' ATEX 99/92/EC (ATEX 137) seeking to ensure that people are protected against the risk of blast injuries or asphyxiation by dangerous substances. 
Updated ATEX legislation that came into force in 2016 is Directive 2014/34/EU and assists with establishing a uniformity to the approach taken when supplying and distributing equipment for explosive atmospheres. The UK Health & Safety Executive implemented ATEX 137 in the form of DSEAR, an abbreviation for Dangerous Substances & Explosive Atmospheres Regulations, which became incorporated in UK law on 30 July 2006.
Everyone involved in the specification, manufacture, installation, and use of equipment in flameproof zones bears some degree of responsibility towards ensuring that the law concerning flameproof equipment is upheld. It may be worth pointing-out that company chief executives are particularly exposed in this respect and could face imprisonment for a serious non-compliance. Therefore the ATEX Directive ensures that when placing products on the market, or using them for their own purpses, manufacturers and authorised representatives shall ensure that they have been designed and manufactured in accordance with the essential health and safety requirements set out in supporting legislation. (see BS EN14986:2017 standards point below.  

Directive Compliant ATEX Fan Constructions Using Permissible Material Pairings
Why are Permissible Material Pairings so Important? 

In the normal operation, or in the event of malfunctions (whether standard or rare), possible friction caused by areas of contact can occur. As stated in the ATEX directive, and adopted into UK legislation, potential areas of contact between the rotating elements and fixed components of equipment for use in potentially explosive environments, should be manufactured from materials in which the risk of ignition caused by friction and friction impact sparks, hot spots or hot surfaces is minimised. This applies specifically to the construction and manufacture of explosion proof industrial fans. Ignition risks cannot be completely eliminated but can be significantly reduced by taking suitable constructive measures for avoiding ignition sources. European and UK Directives are clear on the permissible material pairings that are suitable to reduce the ignition source caused by friction of these two areas: rotating and fixed.
Material pairings are considered carefully by fan manufacturers and authorised bodies, who use their theoretical and practical knowledge, coupled with the known application conditions for the environment in question. The safest material pairing and other compulsory technical specifications that determine how a product is chosen for an explosive environment by taking a full holistic view of the ATEX environment. Material pairings are devised and communicated in legislation documentation to minimise the risk of an explosion. Industrial fans in systems or machinery, are generally not supervised continuously and contact between rotating and stationary, fixed components may occur in a particular area for an unknown amount of time, potentially in long intervals.


BS EN 14986:20217 Standards: Mechanical Design Criteria of Fans for Explosive Atmospheres

Even though Britain has left the European Union, there are still European laws, legislative pieces and standards that have been adopted as a British standard or as formal guidelines. One example is the European standard EN 14986:2017 which has the status of a British standard through BS EN 14986:2017. EN 14986:2017 is known as the “Design of fans working in potentially explosive atmospheres” legislation and specifies the constructional requirements for ATEX fans constructed in Group IIG (Suitable for non-mining gas environments) of explosion groups IIA, IIB and hydrogen, categories 1 (zone 0), 2 (zone 1) & 3 (zone 2), and Group IID (Suitable for non-mining dust environments) categories 2 (zone 21) and 3 (zone 22) for use in explosive atmospheres.

What does BS EN 14986:2017 cover?

The standard sets out the requirements for the design, construction, testing and marking of complete fan units intended for use in potentially explosive atmospheres in air containing gas, vapour, mist and/or dusts. These atmospheres may exist inside, outside or both inside and outside of the fan.   The standard is applicable to fans working in ambient atmospheres and with normal atmospheric conditions at the inlet, having: — absolute pressures ranging from 0.8 bar to 1.1 bar, — and temperatures ranging from −20 °C to +60 °C, — and maximum volume fraction of 21 % oxygen content, — and an aerodynamic energy increase of less than 25 kJ/kg.   So you don’t have to read the entire standard, we’re covering a small section in this article to assist you in ensuring the ATEX fan you purchase is designed, built, and specified in line with the legal guidelines.  

BS EN 14986: 2017 Standards: Mechanical Design Criteria of Fans for Explosive Atmospheres

Section 4.4.1 of the standard describes how industrial fans should be designed to make them suitable for placement on the EU or UK market, in explosive atmospheres.  


“Fans for operation in potentially explosive atmospheres shall be of rigid design.”  


There’s lots of aspects that cover rigid design, and to test this fan, manufacturers should complete impact tests. “Impact testing should be undertaken on casings, supporting structures, guards, protective devices, and other external parts. Then if the deformation resulting from these tests at the most vulnerable point is so small that the moving parts of the fan do not come into contact with the casing, then the component is classed as having a rigid design.” Therefore, any fan design that’s placed on the market will have been impact tested using approved testing procedures and these results will have been sufficient to pass the tests. 

Clearance between Rotating Elements and the Fan Casing

The most important safety feature of any industrial fan construction, to minimise ignition, is the clearance between the rotating elements and the fan casing. This is clearly stated in BS EN 14986 at clause 4.4.2. “The minimum clearances between rotating parts such as the impeller and fixed parts, such as the fan casing, shall be at least 0.5% of the relevant contact diameters (diameter of the rotating part at the point where it can contact a stationary part) of the finished component, but shall not be less than 2mm in the axial or radial directions nor need be more than 13mm.” The fan manufacturer should design and construct the fan ensuring that the clearances are well maintained under all conditions covered by the intended use.  Clearances may change with rotation, temperature and due to vibrations or belt drive tension. Clearances should be adhered to in application considering potential casing distortion, ductwork and pressure drops that may affect.  

Fan Casing

To satisfy the mechanical design requirements specified in the standard, the fan casing should be of a substantially rigid design with leakage protection, adequate shaft seals and fully welded joints. As shaft seal leakage rate may increase over time, on request the manufacturer should provide information about the maintenance requirements for the seals. The fan should be capable of withstanding the lowest inlet pressure that can be generated by the fan itself when the inlet is closed, without causing contact between the casing and moving parts. Leakage declaration is compulsory when the internal and external zones of the fan are different.  

Impellers

Impellers shall be of a rigid design and shall be able to withstand a test run at a minimum of 115 times the maximum operational rotating speed for at least 60 seconds without causing an ignition risk, i.e. the impeller shall not contact the casing. An impeller design that enables a primary stress calculation based on 2/3 of the yield stress shall be deemed to satisfy the requirements for a rigid design without testing. The security coefficient at the rotating element in our tests is a minimum of 20%. This information is recorded in the technical record.   If you’re unsure about the type of explosion proof zone you require and you have the hazardous area classification to hand, give our technical explosion proof fan experts a call or email salesaxair-fans.co.uk and we’ll talk you through the concepts, jargon and if we have the necessary information, we’ll supply a fan suitable for your application.


We ensure that all of our ATEX fans are constructed in line with the mechanical design criteria of fans for explosive atmospheres legislation.

DSEAR Regulations and Hazardous Area Assessments for Hazardous Environments

Whether your work activities create, control or release flammable gases or vapours, such as vehicle paint spraying, exhausting toxic fumes from production activities, or you handle fine organic dusts such as grain flour or wood, a DSEAR audit will ensure you meet the relevant legislation for your industry and reduce the risk of serious injury or explosions. In short if you think there is a risk of explosion with any of the substances or activities being undertaken, a hazardous areas classification can ensure you stay on the right side of safe, protecting systems, processes, buildings, and employees from harm.

There are lots of companies in the UK that can be contracted to complete a risk assessment and compile a hazardous area document tat can be used to source equipment for potentially explosive environments. Important Information In line with the ATEX Directive it is strictly the responsibility of the end user to undertake a DSEAR risk assessment to ensure that ATEX classifications are properly defined in terms recognised by ATEX 2014/34/EU. Please contact SGS on 0151 350 660 or visit www.sgs.co.uk to book an assessment.

Please note that under DSEAR regulations, customers are required to explicitly state their hazardous area classification information before a selection can be made. If you're not sure who to contact to obtain this, we can supply organisations that can help you to remain compliant and safe.  


Understanding ATEX Gas and Dust Zones
The ATEX gas or dust zone is required in all occasions of fan selection. The ATEX zone determines the frequency an presence of the hazardous gas or dust in the application, so that the equipment protection level can be selected correctly. 


When is the gas or dust present in the area the fan will occupy? 
- rarely (zone 2 or 22) - level c required
- ocassionally (zone 1 or 21) - level b required
- always (zone 0 or 20) - level a required
Zones 0, 1 and 2 relate to gases and vapours, while zones 0, 21 and 22 relate to combustible dusts. 
Equipment protection levels:
- highest level protection - level a
- moderate level protection - level b
- standard level protection - level c

ATEX zones for gases/vapour:

Zone 0 (gases/vapours) or Category 1G: an area in which an explosive mixture is continuously present or present for long periods.

Zone 1 (gases/vapours) or Category 2G: an area in which an explosive mixture is likely to occur in normal operation.

Zone 2 (gases/vapours) or Category 3G: an area in which an explosive mixture is not likely to occur in normal operation and if it occurs it will exist only for a short time.

ATEX zones for dust:

Zone 20 (dusts) or Category 1D: an area in which an explosive mixture is continuously present or present for long periods.

Zone 21 (dusts) or Category 2D: an area in which an explosive mixture is likely to occur in normal operation.

Zone 22 (dusts) or Category 3D: an area in which an explosive mixture is not likely to occur in normal operation and if it occurs it will exist only for a short time.

Temperature Classes (T-Classes) and Auto Ignition Temperatures
Temperature classes, also known as T-classes, are designed to prevent the auto-ignition of gases and dusts.
Auto-ignition is the lowest temperature that a gas or dust will spontaneously ignite in air, without a spark or flame, due to its own heat in its environment, causing an explosion. Every gas on earth, as taught in chemistry has an ignition temperature. 

T-classes help to choose ATEX components for use with specific gases and dusts. 
Hazardous area apparatus is classified according to the maximum surface temperature produced under the maximum operating capacity at an ambient temperature of 45°C, or as otherwise specified. For example a motor. The standard classifications are:

T1     450°C
T2     300°C
T3     200°C
T4     135°C
T5     100°C
T6     85°C
As highlighted, this is the lowest temperature at which a gas, vapour or dust will b ignited without a spark or flame. 
Example:
Hazardous Gas: Hydrogen
Ignition Temp: 584.85°C
T Class: Greater than 450°C therefore T1
The maximum surface temperature on components used within the hazardous are containing Hydrogen should not exceed 450°C to prevent the auto ignition of Hydrogen gas. All equipment that generated a surface temperature greater than 450 cannot be used in a Hydrogen atmosphere. 
ATEX Motor Definitions used In ATEX Fans
While all ATEX fans should be certified Ex h to show that they are mechanically constructed in line with ATEX Directive guidelines, so should the electrical parts. This includes the ATEX ratings of the motors, whether standard or external rotor motor. 

For gas environments, the protection principle ensures that an ignition does not occur from sparks and arcs from the motor. 
Ex eb - increased safety, explosion protected - suitable for zone 1
Ex ec - increase safety but the lowest and normal level of ATEX protection, also known as reduced risk protection and for motors is non sparking - suitable for zone 2
Ee Db - flameproof - suitable for zone 1

Ex tb - offers a high level of protection in category 2 / zone 21 dust applications

Ec tc - offers a normal level of protection in category 3 / zone 22 dust applications

Authorised Representatives

A manufacturer may appoint an authorised representative to safely distribute, integrate and sell ATEX components into their respective markets. An authorised representative shall perform the tasks specified in the mandate received from the manufacturer. 

Axair act as the authorised representative for SEAT Ventilation, enabling us to act as the leading party for the sale and distribution of ATEX carbon loaded polypropylene fans into the UK hazardous area market. All technical certifications are dutifully carried out by SEAT Ventilation, with technical documentation and ATEX certificates available for all polypropylene fans.