Method of environmental sealing

A method of envorinmentally sealing a pipe, cable or harness substrate by means of a sheet of polymeric material and a heat-recoverable fabric, which method comprises:

• (a) installing around the pipe, cable or harness substrate the sheet of polymeric material (i) that will conform dimensionally with the fabric when the fabric is recovered, (ii) having a viscosity of at least 5000 poise at a temperature T, (iii) that will not flow through the fabric during recovery thereof and (iv) that has one surface that will adhere to a substrate when heated;
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• (b) installing around the sheet of polymeric material a heat recoverably woven, knitted or braided fabric such that after installation the fabric has a tubular configuration around the pipe, cable or harness substrate, the fabric comprising fibres with will recover when heated to a recovery temperature (T) thereof, of from about 80.degree.-250.degree. C., the fibres having a tensile strength of at least 0.1 MPa at their recovery temperature;
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• (c) heating the fabric to cause it to engage the pipe, cable or harness substrate, and the sheet of polymeric material and cause the sheet to adhere to the substrate.