Fire Resistance & Cable Cleats – Surviving Fire, Flame & Extreme Heat

Published 16 Mar 2018

Cable Cleats – Undergoing Fire Resistant Testing

• Uploaded By Chris Dodds – Thorne & Derrick Sales & Marketing Manager

Cable Cleats

There are currently no European or IEC standards for fire rated cable cleats or clamps, although there are requirements within other standards that can be followed to prevent unsuitable cable cleats being specified and installed.

The international standard IEC 61914 requires non-metallic and composite cleats to have adequate resistance to flame propagation only.

UL94, the standard for Safety of Flammability of Plastic Materials for Parts in Devices and Appliances, is a plastics flammability standard that classifies plastics according to how they burn in various orientations and thicknesses.

Adherence to its V-0 rating for polymer cable cleats should be demanded by specifiers.

For information UL94’s V-0 rating means that burning stops within 10 seconds on a vertical specimen; drips of particles allowed as long as they are not inflamed.

The use of the description LSF (Low Smoke & Fume) is common terminology with regard to polymers, but is misleading as it doesn’t relate to any published standard and so can be interpreted in a wide variety of ways.

To ensure complete assurance of performance in a fire, all Ellis Patents plastic cable cleat products have undergone testing at the Building Research Establishment (BRE) in line with the London Underground 1-085 Standard specification with regard to:

• Smoke emission
• Limited oxygen index
• Toxicity of fumes

The appropriate cleats are listed in the London Underground Approved Products Register.

Identification numbers are 360, 361,362, 363, 364, 365 and 1661.

A great deal of focus is placed on fire rated (FP) cables and their performance in fire, but very little attention is given to the cable fixings used to secure these cables.

Given that FP cable is typically rated for operation in temperatures ranging from 850°C to 950°C then the use of plastic cable cleats or clamps is clearly inappropriate.

Even aluminium only has a melting point of 660˚C, which means it would fail to support FP cables in a fire. To counteract this shortcoming, Ellis manufactures the Phoenix range of cable cleats for use with FP cables. Independently tested by Exova Warrington fire and BRE, all products in the Ellis Patents range are proven to perform to the same level as the FP cables ensuring continuous operation in the event of fire.

Ellis Patents Phoenix Cable Cleats – Fireproof & Fire Rated

Cable Cleats Blogs

• IEC 61914 – Cable Cleats & Short Circuit Protection Calculations
• Cable Cleats – London Underground 1-085 Standard For Fire Safety Performance 
• Stainless Steel Cable Cleats – Preventing Galvanic Corrosion Of Cable Fixings

LV, MV & HV Jointing, Earthing, Substation & Electrical Eqpt

Thorne & Derrick International are specialist distributors of LV, MV & HV Cable Installation, Jointing, Duct Sealing, Substation & Electrical Equipment – servicing UK and global businesses involved in cable installations, cable jointing, substation, overhead line and electrical construction at LV, 11kV, 33kV and EHV.

THORNE & DERRICK Product Categories: Duct Seals | Cable Cleats | Cable Glands | Electrical Safety | Arc Flash Protection | Cable Jointing Tools | Cable Pulling | Earthing | Feeder Pillars | Cable Joints LV | Joints & Terminations MV HV 

Further Reading

• Ellis Patents – Cable Cleats Size: 6.67 MB
• Ellis Patents – The Black Book Guide To Cable Cleats Size: 1.44 MB