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FIRE SAFETY => Fire Risk Assessments => Topic started by: alfi on March 14, 2012, 08:51:06 AM

Title: a bit of advice
Post by: alfi on March 14, 2012, 08:51:06 AM
Folks,

could i ask for some opinions please. while completing a FRA yesterday i was checking ethe passive protection in the service risers which houses HV cables running to various floors, i noted that as usual some penetrations had been poorly filled wih the usually standard expanding foam and not in line with BS476 . i then noticed a new PVC  waste pipe had been installed, this passes through the floors/ceilings, previoulsy it would have been cast iron with far more fire reistance properties. where the pipe passes throught the floor/ceiling this is wehere they used the standard foam to seal the gap, obvioulsy totally unacceptable, my query is would you insist on Seals which consist of two half shells of metal which are clipped around the pipe and anchored to the structure. The metal shell contains an intumescent material which reacts under i heat which comply with BS476 part 20 or any other ideas chaps. I don't want to over speciafy if a simpler solution and cheaper option is available, and i hold my hands up on this one i do need a little advice :'( 
Title: Re: a bit of advice
Post by: nearlythere on March 14, 2012, 09:09:29 AM
What size of pipe is it?
Title: Re: a bit of advice
Post by: alfi on March 14, 2012, 09:13:29 AM
6 inch
Title: Re: a bit of advice
Post by: William 29 on March 14, 2012, 09:45:55 AM
The new guide by the ASFP will be of use http://www.asfp.org.uk/webdocs/Guide_to_inspecting_PFP_for_Fire_Risk_Assessors.pdf

Extract below for you.  I have called them on occasions and sent photos of FR breaches and found them to be helpful in providing a second opinion.

8.4.2.1. Penetrating services (cables and pipes)

The assessor will need to ensure that any services penetrating walls or floors abutting escape routes are adequately sealed where they penetrate the wall or floor. He should pay particular attention to penetration services above suspended ceilings where they might have been installed and not made good afterwards. The presence of any through holes or gaps is not acceptable and these must be made good with appropriate tested/certificated construction that is compatible with the existing penetration seal.

There are a variety of proprietary materials and products used to seal penetrations including intumescent collars and wraps, fire resisting mortars, coated mineral fibre batts, fire resisting pillows etc. The FRA is not expected to be an expert in all of these, but he should be aware of the limitations of the generic material types. The assessor should be particularly vigilant if he discovers the use of expanded foam used as a penetration sealing material. Most of these are tested as narrow linear gap seals and will not work in a large penetration seal. Further guidance is given in annex G including guidance on PU foams.
Title: Re: a bit of advice
Post by: alfi on March 14, 2012, 10:10:18 AM
Thnaks buddy very useful link   :)
Title: Re: a bit of advice
Post by: William 29 on March 14, 2012, 10:23:35 AM
No problem  :)
Title: Re: a bit of advice
Post by: Tom W on March 14, 2012, 10:58:21 AM
6 inch

Thats what they all say  ;)
Title: Re: a bit of advice
Post by: Fishy on March 15, 2012, 11:40:39 AM
For retro-fit, the surface-mounted collars are best, provided that the substrate to which they're fixed is robust - dense concrete would be fine, for example.  Manufacturers don't often rate surface-mounted collars for lightweight horizontal constructions (e.g. timber floors). 

Installers need to follow the manufacturer's instructions to the letter (not fixing them using plastic wall plugs, for example)!

If you're not sure of your ground, I wouldn't try writing a detailed spec - just make general recommendations & advise the use of specialist, competent contractors.
Title: Re: a bit of advice
Post by: Psuedonym on March 15, 2012, 05:43:53 PM

If you're not sure of your ground, I wouldn't try writing a detailed spec - just make general recommendations & advise the use of specialist, competent contractors.
 



IMO Best piece of advice in any scenario. Point out the errors but let them emloy a specialist to finish the decision making process.