Comments on: Equipment Protection Levels and all that http://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/ Thoughts and Comments on what is happening in the Ex field Fri, 03 Jul 2009 11:09:33 +0000 http://wordpress.com/ hourly 1 By: Estellito Junior http://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-1453 Estellito Junior Thu, 24 Apr 2008 23:39:27 +0000 https://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-1453 This is a very important safety measure, as we know that OSHA is a legal requirement for USA, beyond a simply technical one. Regarding the OSHA “permitted installations”: 1) intrinsically safe, 2) approved for the hazardous (classified) location, or 3) safe for the hazardous (classified) location, please, note that it is not allowed to consider “the consequences of an explosion” to install equipment with a “lower safety degree” of those required by American standards. Comparing with the IEC EPL method, where a “lower EPL than required” is allowed if “the consequences of the explosion” are “small”, we can say that OSHA method is safer. The EPL method sounds as a “black hole”, where all installation’s “non-conformities” can “disappear” with a snap, simply saying that “the consequence of an explosion is minimal". How may deaths can be considered as “minimal consequence” of an explosion? This “EPL” seems to be against all safe requirements given by IEC Ex standards. This is a very important safety measure, as we know that OSHA is a legal requirement for USA, beyond a simply technical one.
Regarding the OSHA “permitted installations”: 1) intrinsically safe, 2) approved for the hazardous (classified) location, or 3) safe for the hazardous (classified) location, please, note that it is not allowed to consider “the consequences of an explosion” to install equipment with a “lower safety degree” of those required by American standards.
Comparing with the IEC EPL method, where a “lower EPL than required” is allowed if “the consequences of the explosion” are “small”, we can say that OSHA method is safer.
The EPL method sounds as a “black hole”, where all installation’s “non-conformities” can “disappear” with a snap, simply saying that “the consequence of an explosion is minimal”.
How may deaths can be considered as “minimal consequence” of an explosion?
This “EPL” seems to be against all safe requirements given by IEC Ex standards.

]]> By: Steve Last; The ATEX and DSEAR Site http://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-157 Steve Last; The ATEX and DSEAR Site Fri, 06 Apr 2007 18:59:17 +0000 https://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-157 We are involved in ATEX compliance within the waste industry and in particular for landfill sites. The responsible person is usually considered to be the Landfill Site Manager. As you can imagine the system needs to be pretty intuitive to be useful to these guys, who are usually recruited to be good general managers rather than technical people. Complex although the compliance rules are, it really is still necessary for non-specialists to at least be able to understand labelling matters in concept at least very readily. Landfill gas is 60% methane, on average, so there is plenty of gas around to cause explosion risk! The labelling system on the leachate extraction pumps, and other related equipment which is installed in landfill sites is important, but poorly understood. Some operators don't use explosion rated equipment pointing out that they have used the same pumps for at least 20 years without incident, while others would be appalled. In working for clients across the landfill industry we find surprising variations in implementation of ATEX (DSEAR in the UK). The root of the problem of compliance does lie to an extent in the complexity of the labelling, which in my view is quite simply incomprehensible to many in the waste industry. However, in my experience of real life explosion incidents at landfills, it has not been ensuring the correct rating of the equipment which incurs the highest risk at all, it has been shown far more important to simply rigorously enforce of the site "No Smoking" rules, and avoid making sparks. We are involved in ATEX compliance within the waste industry and in particular for landfill sites. The responsible person is usually considered to be the Landfill Site Manager. As you can imagine the system needs to be pretty intuitive to be useful to these guys, who are usually recruited to be good general managers rather than technical people.

Complex although the compliance rules are, it really is still necessary for non-specialists to at least be able to understand labelling matters in concept at least very readily. Landfill gas is 60% methane, on average, so there is plenty of gas around to cause explosion risk!

The labelling system on the leachate extraction pumps, and other related equipment which is installed in landfill sites is important, but poorly understood. Some operators don’t use explosion rated equipment pointing out that they have used the same pumps for at least 20 years without incident, while others would be appalled.

In working for clients across the landfill industry we find surprising variations in implementation of ATEX (DSEAR in the UK). The root of the problem of compliance does lie to an extent in the complexity of the labelling, which in my view is quite simply incomprehensible to many in the waste industry.

However, in my experience of real life explosion incidents at landfills, it has not been ensuring the correct rating of the equipment which incurs the highest risk at all, it has been shown far more important to simply rigorously enforce of the site “No Smoking” rules, and avoid making sparks.

]]> By: mtlinst http://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-74 mtlinst Tue, 30 Jan 2007 12:34:49 +0000 https://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-74 The IEC 'general requirements' IEC 60079-0 does allow marking on small items to be reduced. Interestingly the current draft for voting has a clause which states 'In the case of extremely small electrical equipment and extremely small Ex Components where there is no practical space for marking, a marking linked to the equipment or Ex Component is permitted. This marking shall be identical to the marking 29.2 , 29.3 and 29.4, as applicable, shall appear on a label provided with the equipment or Ex Component for field installation adjacent to the equipment or Ex Component' It will be interesting to see a practical embodiment of this clause. particularly as related to Ex Components. There are some potential problems if a number of component labels have to be attached to an assembly. The ATEX apparatus directive does not include a derogation for small components but the 'Guidelines' do. The requirement is for the CE mark. the Ex marking and the manufacturers identification. Fortunately just occasionally 'common sense' prevails and a smaller amount of marking as quoted in your example provides the necessary information. Whether it complies with the letter of the standard and directive is debatable. However it does not really matter since the equipment is adequately safe. I still feel a reference back to the fuller information on a web-site is the way forward. It is possible that the next edition of the IS apparatus standard [five years away ??] will not require marking of the terminal parameters since they are only of use in the system design. The parameters will still be included in the apparatus certificate. The IEC ‘general requirements’ IEC 60079-0 does allow marking on small items to be reduced. Interestingly the current draft for voting has a clause which states

‘In the case of extremely small electrical equipment and extremely small Ex Components where there is no practical space for marking, a marking linked to the equipment or Ex Component is permitted. This marking shall be identical to the marking 29.2 , 29.3 and 29.4, as applicable, shall appear on a label provided with the equipment or Ex Component for field installation adjacent to the equipment or Ex Component’

It will be interesting to see a practical embodiment of this clause. particularly as related to Ex Components. There are some potential problems if a number of component labels have to be attached to an assembly.

The ATEX apparatus directive does not include a derogation for small components but the ‘Guidelines’ do. The requirement is for the CE mark. the Ex marking and the manufacturers identification.

Fortunately just occasionally ‘common sense’ prevails and a smaller amount of marking as quoted in your example provides the necessary information. Whether it complies with the letter of the standard and directive is debatable. However it does not really matter since the equipment is adequately safe. I still feel a reference back to the fuller information on a web-site is the way forward.

It is possible that the next edition of the IS apparatus standard [five years away ??] will not require marking of the terminal parameters since they are only of use in the system design. The parameters will still be included in the apparatus certificate.

]]> By: Bruce Durdle http://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-70 Bruce Durdle Wed, 24 Jan 2007 00:33:01 +0000 https://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-70 There is a precedent in that, where equipment (such as prox probes) is too small to allow the full catastrophe to be included, certificate number and entity parameters only are acceptable. Pepperl and Fuchs for instance print these on the cable adjacent to the probe. There is a precedent in that, where equipment (such as prox probes) is too small to allow the full catastrophe to be included, certificate number and entity parameters only are acceptable. Pepperl and Fuchs for instance print these on the cable adjacent to the probe.

]]> By: mtlinst http://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-6 mtlinst Fri, 01 Sep 2006 06:49:34 +0000 https://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-6 This appears to have just been published acc the IEC Newsletter IEC 60079-26 Ed. 2.0 (2006-08) Preview Price: CHF 97.00 Explosive atmospheres - Part 26: Equipment with equipment protection level (EPL) Ga Steve/MTL This appears to have just been published acc the IEC Newsletter

IEC 60079-26 Ed. 2.0 (2006-08) Preview Price: CHF 97.00
Explosive atmospheres – Part 26: Equipment with equipment protection level (EPL) Ga

Steve/MTL

]]> By: Geoff Bottrill http://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-4 Geoff Bottrill Wed, 30 Aug 2006 21:16:21 +0000 https://mtlinst.wordpress.com/2006/08/28/equipment-protection-levels-and-all-that/#comment-4 EPLs? Yet another mark to appear on a label? The labelling of apparatus already causes considerable confusion to the poor technician. Could I plea for the need for greater unity and consistency in the way Notified Bodies produce Apparatus Certificates? Then maybe we can rely on the certificate number and the website idea! EPLs? Yet another mark to appear on a label? The labelling of apparatus already causes considerable confusion to the poor technician. Could I plea for the need for greater unity and consistency in the way Notified Bodies produce Apparatus Certificates? Then maybe we can rely on the certificate number and the website idea!

]]>