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Polystyrene Removal
Many of the roofs of houses, bungalows etc., during the
1970's / early 1980's have polystyrene (E.P.S.) as a loose fill insulation
material. It has been noticed in many cases where polyvinyl chloride (PVC)
sheath electrical cables have been run through the E.P.S. insulation that
some form of reaction is occurring.
When this happens a loss of plasticiser from the cables is to be expected,
and the plasticiser migration is accelerated at higher temperatures. Thus
where the cables are surrounded by expanded polystyrene thermal insulating
material, and especially if they are over-loaded, more significant changes
might be expected. In these circumstances the sheaths will become brittle
and the effective working life shortened. Care would then be needed if
the cables were disturbed.
In contact with PVC plasticiser expanded polystyrene is partly dissolved
and becomes tacky. Eventually the E.P.S. shrinks back as its structure
collapses. The long-term effect is certain to be shortening of the working
life of the cables and potential risk of fire.
United Insulations have brought over machinery from America designed
to remove the polystyrene from loft spaces, and with help of a Government
grant a safe and more suitable insulation material can be installed.
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