Time to celebrate 20 years of Atex

The Directive was to ensure that it was adopted into the legal system of each member of the European Community. This was to ensure that 'Atex' equipment manufactured or sold in the European Community complied with the directive. Once a product had been tested and approved by a notified body such as Baseefa in the UK and PTB in Germany, then it could be sold anywhere in the 'common market' area. In the UK the embodiment of the Atex Directive came into law with the introduction of DSEAR.

 

So how successful has it been, and does everyone now fully understand it?

In meeting its aims Atex has been very successful, however it is still a complex and specialist field. The manufacturers, and test houses understand the complexities of it, but many users are reliant on specialist companies to supply, service and maintain their Hazardous Area Equipment. In this way they generally comply but do not always understand why. 

 

The AEMT has trained member companies internationally to be specialists able to repair and maintain hazardous area equipment. It operates an International Ex Register of Companies that are trained and equipped to service Atex equipment to IEC standards.

Atex is derived from the first two letters of the French description: 'Atmosphères explosives'. There are two Atex directives:

•  Atex 95 which is the equipment directive 94/9/EC, which I will concentrate on here. It is for the manufacturer of electrical and mechanical equipment to conform to.

•  Atex 137, the workplace directive 99/92/EC is to ensure best practice health and safety protection for employees working in potentially hazardous atmospheres which became mandatory in July 2006.

 

These are not laws, but are to be embodied into the law of each member country. They are not standards, and standards have had to be updated to ensure that manufacturers and users can use the latest relevant European and international standards to comply with the requirements of Atex. The Atex documents are available to download free from the European Commission’s website.

 

Certainly Atex has been successful and has stood the test of time, but after 20 years it is due to be updated and will be repealed on 20 April 2016. On that date the new updated version Directive 2014/34/EU comes into effect. Although the changes appear relatively minor, the fact that 94/9/EC is being repealed is creating concern among the notified bodies. It looks as though certificates referring to Atex 94/9/EC may not be able to be updated once it has been repealed.

 

But enough of the paperwork, how did Atex come about and what is its history. This goes back just over a 100 years. In 1913 at Senghenydd Colliery in North Wales 439 miners were killed in a disastrous explosion in the mine. The enquiry felt that the explosion of firedamp and coal dust had been caused by the sparks from the electric bell system the miners were using. Two bare wires going through the mines were bridged with a metal object to sound the bell. 

 

The enquiry led to the development of the first British Standard BS229 for Flameproof equipment, first published in 1926. This standard for the Flameproof, FLP, and ex d designs remained in force, with an update in 1957, all the way through to 1971. Considering these machines are now around 50 years old it is surprising how many still crop up, and as long as a risk assessment feels that the motors are safe in the location in which they are being used, then they can still remain in service. The Ex d machine became suitable for use on the surface as a Group II machine, as opposed to Group I for underground mining.

 

In America and Canada similar machines are known as explosion proof. The Ex d machine is still the favoured machine for Zone 1 areas, and is now often used with an Exe increased safety terminal box. The Germans favoured the Ex e machine concept of increased safety with no arcs and sparks, which is now a recognised form of protection to comply with Atex in a Zone 1 area.

 

In America the Ex e concept has only recently been recognised. Ex n or non-sparking enclosures are suitable to meet Atex requirements in Zone 2 areas. Other protection concepts such as ex p, ex i, ex o, ex m, etc. all had existing standards and were also suitable for use in the appropriate Atex zoned areas. Only Ex ia and Ex ma are suitable for Zone 0 areas, where an explosive atmosphere may be expected to be present all of the time. 

 

The above Protection concepts were already well recognised when Atex was introduced, however the introduction of Atex focused minds on standards to protect workers in areas of combustible dusts. This is surprising when coal dust was recognised as a major part of secondary explosions in the 1913 disaster at Senghenydd Colliery.

 

In September 1921 more than 500 people were killed at a BASF fertiliser plant in Oppau in Germany. With the secondary explosions from dust disturbed by the first explosion, the devastation caused by dust can be catastrophic. As such it is surprising that the first standards for combustible dust equipment came in, in the late 1980s and 1990s, and became much higher profile through the adoption of the Atex Directives. This now means that fertiliser plants, grain silos, sugar plants, flour, wood dust, and many other processes using natural and organic products have to take account of the risk of a dust explosion. The dust from certain metals such as Aluminium, bronze, and zinc, have also lead to some major plant explosions.

 

Atex also covers the electrostatic sparks.  The spark that caused the Hydrogen Balloon of the German Hindenberg airship to explode into a fireball when docking in May 1937 in New Jersey, caused 35 deaths ending the era of the passenger carrying airships.

 

Finally Atex included problems caused by mechanical items, such as the heat caused by failed bearings, and materials that may cause a spark, such as fans and fan covers, conveyors and so on. It has long been of concern to electricians that they are fitting an electric motor designed not to exceed a T3 surface temperature of 200° C in an area with kerosene as a potential source of ignition, and yet some mechanical plant close by may be operating at well above the safe temperature. Atex focused Cenelec in Europe to come up with standards for the mechanical concepts for equipment such as pumps, gearboxes, conveyors, etc. These Cenelec standards in the EN 13463 series were introduced from 2001 onwards to ensure that these mechanical items were also safe to use in Hazardous Areas. In a stroke this has more than doubled the amount of equipment that needed to be Atex compliant, and regularly inspected.

 

So has Atex been a success? Undoubtedly it has gained a great deal of credence and is now the favoured choice of equipment worldwide for the oil industry outside the USA and Canada. One will never know the number of lives that it has saved, but accidents still happen, and the cost of the accidents can be huge.

 

At Buncefield the failure due to poor maintenance of a float control valve resulted in no deaths, but damage estimated at more than a billion pounds. Without a spark, it would not have been such a major disaster. The spark was possibly caused by a generator outside the zoned areas and was a very expensive spark. BP has put aside a 20 billion dollar fund to compensate for the Deepwater Horizon failure in the Gulf of Mexico in 2010. An expensive spark and mechanical failure.

 

Atex has been very worthwhile and although primarily introduced to create a common market for Hazardous Area Equipment of a universal high standard, it has also meant that any equipment coming from outside Europe cannot be used in Europe unless it also has been tested to comply with the Atex Requirements. For this reason it is rare to see American UL equipment being used in Europe, but then the USA will not allow Ex equipment into America unless it complies with UL or FM. So a bit of tit-for-tat, and commercially it must be considered a great success. We will never know the number of lives it has saved, but the European safety records for safety in mines etc. are much better than countries outside the Atex area. 

 

So happy birthday to Atex, one very positive benefit to emerge from the European Union.

 

AEMT members 

The members of the AEMT form one of the largest groups of companies, operating from just under 500 locations internationally, that service and recondition motors, pumps, fans and gearboxes. Most are adept at establishing whether equipment is correctly sized and have an array of condition monitoring and reconditioning skills to be able to carry out well managed equipment maintenance to prevent unexpected downtime.  In the right environment they can ensure equipment has a long, trouble-free and energy efficient life. They are available internationally and many are used to working on Hazardous Area Equipment, or in confined areas.