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STANDARDS
EuroClass
A ca
Reaction to fire
Gross heat of combustion [ EN ISO1716 ]
Additional classifications and parameters Reaction to fire Flaming droplets Acidity
None
B1 ca
B2 ca
C ca
D ca
E ca
F ca
Heat release [ EN 50399 ]
Flame spread [ EN 50399 and EN 60332-1-2 ]
Heat release [ EN 50399 ] Flame spread [ EN 60332-1-2 ]
Flame spread [ EN 60332-1-2 ] s1 , s2 , s3 [ EN 50399 ]
Smoke transmittance s1a , s1b [ EN 61034-2 ]
Falls to meet E ca
d0 , d1 , d2 [ EN 50399 ]
None a1 , a2 , a3 [ EN 60754-2 ]
A higher classification As of 1st July 2017 , it ’ s fair to say that almost all cables installed would have been EuroClass ‘ Eca ’. But unfortunately , unless they meet ‘ Dca ’, cables claiming LSOH or LSZH performance they now receive no additional classification for these characteristics . Now higher EuroClass designations are being introduced to meet predicted installation demands of EU member states . Each member state can , and will , interpret their building and fire prevention practices in terms of EuroClass requirements .
However , until the publication of BS 6701 2016 : AM1 2017 , it was not known to what extent the continuing use of EuroClass ‘ Eca ’ would be acceptable in the UK or whether a higher classification cable would be required ? Before providing the answer , it ’ s useful to understand the framework within which BS 6701 sits and worth emphasising that this is a British Standard , not European .
BS 6701 is the appropriate reference for telecommunications systems from BS 7671 ‘ Requirements for Electrical Installations ’, also known as the IET Wiring Regulations which is currently in its 17th edition . These are non-statutory regulations but provide the easiest way to comply with the true national statutory tools that are the Electricity at Work Regulations ( for commercial premises ) and the Building Regulations Part P ( for residential premises ). BS 7671 itself is due to be re-issued next year . There has been some reluctance by the power cable industry to directly apply Euro-classification . Nevertheless , the changes in BS 6701:2016 AM1 : 2017 apply from 30th November 2017 – and are not dependent on changes to BS 7671 .
In order to avoid any confusion resulting from the vague nature of the term ‘ permanently incorporated ’, BS 6701 2016 : AM1 2017 defines two types of cables and is applicable to refurbishments , not just new buildings . ‘ Installation cables ’ are defined as those cables intended to be installed in hidden or otherwise inaccessible pathways – whether or not those cables are terminated . Now pathway is another word for ‘ route ’, so inaccessible pathways are obviously above ceilings , under floors , in walls or in open tray or basket which requires ladders or similar to access them . One area requiring clarification is that cables installed in conduit , ducting or trunking are also considered to be not accessible and are therefore ‘ installation cables ’. According to BS 6701 2016 : AM1 2017 , these installation cables are required to meet the requirements of EuroClass Cca-s1b , d2 , a2 . Cables , other than ‘ installation cables ’, are required to only meet EuroClass ‘ Eca ’ or , where they are not specified under CPR , compliant with the recommended requirements of BS EN 60332-1-2 .
BS 6701 2016 : AM1 2017 provides its universal requirement for ‘ installation cables ’ as a translation from BS 7671 for escape or evacuation routes . This appears to demand more highly specified cables than had previously been installed , but there are three main reasons for this . Firstly , telecommunications can ’ t be jointed without performance degradation . Secondly , building spaces are frequently repurposed and evacuation routes may change – typically without changing the cable installation in them . So even if a cable only passes through on an evacuation route for a small percentage of its total length it will need to meet the most demanding requirements of the spaces it passes through . Thirdly , telecommunications cables are installed on a point-to-point basis leading the presence of large bundles or groups of cables in some areas – and EuroClass Cca is the lowest EuroClass where flame spread testing is conducted using the bundle burn test as opposed to single cable .
Additionally , but not directly linked to its selection in BS 6701 A1 , EuroClass Cca is the minimum EuroClass subject to continual external assessment ( AVCP 1 +). This provides users with increased product confidence and supports ongoing improvements in test procedures undertaken by the Notified Bodies responsible for the performance assessment .
Implications of the standards The contractual implications are that irrespective of whether tenders were issued before or after 30th November 2017 , BS 6701 should be treated as an implicit requirement inside buildings . There is clearly a cost difference between the EuroClass Eca and EuroClass Cca-s1b , d2 , a2 as required by BS 6701 2016 : AM1 2017 and premises owners or their delegated agents should ultimately make the decision whether or not to implement the requirements of the standard . They will be the most knowledgeable about the planned usage of their buildings , and have responsibility for the building safety and other designed elements that will be assessed under BS 9999 , the Code of Practice for fire safety in the design , management and use of buildings and the application of fire safety engineering principles under BS 7974 : 2017 .
As a supplier or installer , it ’ s incumbent to point out the differences and be able to offer both EuroClass Eca and Cca-s1b , d2 , a2 in both copper and optical fibre media for all commercial buildings unless specified otherwise . Forthcoming revisions to BS EN 50174 standards will require that cables not complying with national requirements are required to be installed in cable management systems acting as fire barriers . n
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