BS 3379:2005 pdf download

BS 3379:2005 pdf download.Combustion modified flexible polyurethane cellular materials for loadbearing applications——Specification.

For a combustion modified (CM),high-resilience block material(HB) intended for very severe service(V)with an indentation hardness index (1) of 180 N (170) the designation is CM-HB-V-170(1).
5 Structure and composition
The materials shall consist of polyurethane flexible materials with a network of cells.
NOTE 1 The materials are usually available with cells substantially open and interconnecting and free from abnormalities affectingtheir performance.
NOTE 2 Materials are normally supplied with a slight odour that is neither objectionable nor harmful.
Where a particular colour is required it shall be specified by the purchaser [see Clause 3 item a)].
6 Construction
The materials shall be supplied in block, sheet or strip form, or in moulded or fabricated shapes.
Repaired material shall be deemed to conform to the requirements of this standard if the material used inrepairs is of the same composition and quality as the original product and provided that such repairs donot affect the performance,size and shape.
When components are repaired and fabricated, any adhesives used shall not damage the material and theresulting bonds shall be at least as strong as the material itself.
The area of the bond shall be sufficient to withstand the service conditions, e.g.a bonded thin overlay shallbe bonded over sufficient area to prevent rucking in service.
7 Surface condition
There shall be no loose skin on surfaces.Mould parting marks and other surface blemishes shall be notworse than the quality levels specified by the purchaser [see Clause 3 item b)].
8 Component mass
The mass of a component, when required, shall be as specified by the purchaser [see Clause 3 item c)].