Opinion – Steve Jones, independent consultant10 January 2010
In the past year, the buzz around EN54-24 (and ISO7240-24) for loudspeakers was that it was short on electro-acoustics and long on environmental testing. I tabled a question at the Vienna meeting of TC72, which deals with this standard, asking that a separate version be written so that long-throw CD horns can be used despite them not being tested to EN54-24. I was told that there was already dispensation for the use of such units under the scope which said that “the standard [did] not apply to ‘special’ applications…(explosive atmospheres etc)”, but that included the situation where a long-throw horn was required and nothing else would be suitable. Your article starts quoting that part of the standard, but does not recognise (as I initially failed to do) that the pertinent word was ‘special’ applications, not ‘explosive’ since the wording gave the wrong emphasis.
Why is the standard so heavy on environmental testing? I was told that sometimes when loudspeakers are installed, they don’t work because they have been exposed to severe shock and climatic conditions during transit from the Far East. Type testing to prove that they will withstand such rigours obviates the problem.
VACIE or SSIE?
When is a VACIE not a VACIE? The answer is when it is a SSIE.
Europeans call it ‘voice alarm’ control and indicating equipment, whereas ISO7240- 16 confusingly calls it ‘sound system’ control and indicating equipment. Both terms refer to signal processing and amplification equipment with fault monitoring.
If you need to do a job with a distributed arrangement instead of a centralised arrangement you will probably have to use at least one product that is not type tested as a VACIE/SSIE, and the standards allow this.
Standards and conformity
The EN54 series of standards are (currently) ‘product’ standards, meaning that equipment ony has to perform a function in a stand-alone fashion. A ‘performance’ standard such as EN60849 or ISO7240-19 requires that the end result achieves the required performance.
A certain manufacturer managed to get their national test house (TUV) to certify their product was compliant with EN60849 – this is wrong! When I questioned the chairman of the BSI committee under whom such standards are written, about the power of BSI, or any European Standards Institute, to sanction errant test houses, I was told that they had none.
The EN54 series of standards will be empowered through the Construction Product Directive
This effectively means that any building of any noticeable size must only use products that have been type tested to EN standards. Unfortunately, the same does not apply to the ‘performance’ standards; thus fully badged, type tested, probably very good equipment that is installed badly is ‘compliant’.
The nub of the problem is ignorance. The fire industry is leading the way in providing training for voice alarm. Even then, it is starting from a very low point of knowledge.
The other form of ignorance concerns what the standards require. There are salesmen who pressurise buyers with ‘compliance’ and ‘certification’, yet what they claim has no substantiation in truth. The ignorant buyer considers their word as expert.
Even worse, I come across product R&D people who have a similar misguidance, but actually incorporate it in the product, believing it is a unique selling proposition.
The IE article says “in future [European member states will] replace their local standards with EN54”. This is a classic case of ignorance. All European standards are superior to national standards at all times.
BS5839-8 is more detailed than any EN, but it only has national status. EN54-14 is a performance standard along similar lines to 5839-8 but it has the status of a ‘TS’ – a nonmandatory standard.
There is a need to ‘interpret’ the standards because they are not written for specific applications. The generic nature, and safe refuge of woolliness in authorship, does not help those looking for strict guidance.
In praise of standards
Anyone would think that I did not approve of standards, but I have always championed ‘performance’ standards – those that state what the end result must achieve. And when I say “achieve”, I mean every time, emergency or not.
We are starting to write standards that include such concepts as ‘risk assessment’ and ‘verification’. Risk assessment may have a bad reputation, but it means that you have thought about the problem; come up with the most pragmatic solution; and ensured it is fit for purpose.
Verification is creeping in at last. Provided that the client wants to pay, he can independently verify that what the installer has self-certified, and he has bought, does meet the standards. But a client is only going to pay if he thinks that he will catch a bigger fish in the form of a damages law suit from someone else.
It might just make the industry sit up and think about putting its own house in order – a scare tactic that the client can use against pushy salesmen!
Steve Jones has been in the sound industry for many years, and gained experience of life safety systems for the old and new Wembley Stadium, the Millennium Dome and many other large and public spaces.
As chairman of ISCE in 1989 he chaired the inter-institution working group that produced what is now BS7827. He also joined the BSI committee that deals with BS5839-8, EN54 and ISO7240.