Is there any standard/reference which mandates fire protection of cable trays, even if the cables within it and all accessories and components are fire rated? Is it either of them should be fire protected or both needs to be fire protected?

Seeking advise and opinions.

Regards,

P

Building Regulations Approved Document B, in particular references to compartmentalisation as cable trays often "vanish" through the walls between/inside buildings. Whilst the materials may be fire resistant the gap caused by their routing breaches the fire compartment.

Also BS 9999 Code of practice in the design, managemnt and use of buildings

API 2218 if you want another industrial fire protection standard.

Greater clarity in your queries would be very helpful

For a petrochemical site then API2218 is what you need.

This seems to be a design issue, your contractors should build as instructed by the designers.

For the project you should have a basis of design document, outlining the standards to be followed for the project.

Your Client may also have there own design standards, most of the larger oil/petrochemical companies do and specify what they want - which you hint at.

Have the project completed a HAZID & HAZOp study for the design, how crticial are these cables?

If in the UK, the Principal designer should also be interested in this issue - as part of CDM PD duties

The architect/designer will have drawn up the scheme with a specification of materials to satisfy the regulations and standards

Contractors "down specifying" to boost their profits is something that should always be avoided, and now you have been forwarned this is a route they are considering make sure it gets a very competent inspection before sign off acceptance

If in doubt refer to the person whose professional indemnity you may later be relying upon

So construction contractors are altering what designers have specified as being required to build/maintain the plant.

As previous, you need to go back to the Basis of Design - that will indicate the minimum design standards for the project.

Also any process safety HAZOP studies or Fire & Explosion reports to determine what fire scenarios have been identified and potentially the types of fires that may develop e.g. pool fires, jet fires. That will guide you as to the type of passive fire protection required and where passive fire protection should be applied to primary structures or around vital power supplies.

Glad I'm not working on your project, if construction contractors are altering specifications? if that is happening. 

chas

By the sound of it, there is more to this than entanglement. The poster has sais this is on a petro-chemical site. No-Uk I think.

It hasn't been established what the cables provide power to  - they might provide power to the Emergency Shut Down systems, for example.

Until that is known, its not clear if the cables/cable trays need to have passive fire protection applied/specified.

The Shirley Towers fire in 2010 (in which it was ruled that two firefighters died from exposive to excessive heat after becoming trapped in cabling that had fallen from plastic trays) led to the requirement for cables trays to be made of metal rather than plastic.  The question then becomes how long the tray assembly will stay in place when exposed to fire.  This doesn't necessarily mean that it is fire-resistant but it must maintain structural integrity.

Are the contractors suggesting that cables will remain in place without the trays?  If so, this would suggest that, as well as being adequately suspended, they are under tension and/or have an inherent structural stiffness that would resist sagging.  Seems to be a bit of an ask when the trays would do the job.

To reiterate others' comments, it may not be a duplication of fire resistance that is at issue, it may simply be how the cables will remain suspended under fire conditions.

If I have misunderstood, my apologies.

Regards

Steve