Performed strip 330mm long with round or triangular profile or in 3 kilo blocks. Description: Densyl mastic is a soft mouldable mastic based on saturated petroleum hydrocarbons, inert mineral fillers and organic fibres. Densyl mastic is approved by British Gas (Centrica) for sealing the annular space between carrier pipes and sleeves where services enter buildings below ground level. Ducts below ground can also fill with water and this too would enter the exchange or substation - the duct seal must prevent this.ĭensyl Mastic is a self-supporting non-setting mastic for waterproofing and for sealing service entries and ducts against entry of gas. Spareways without cables must also be sealed. Therefore it is necessary to achieve an effective seal in the space between the cable and the duct. Gas can accumulate in cable ducts and seep into exchanges, substations and switchrooms. Duct seals are similar - telephone and power cables (low and high voltage) are commonly ducted. This ability to permit movement is necessary to allow for soli compaction, settlement or subsidence - it is crucial the duct seal or service entry withstands water pressure and is not detroyed by vermin. The space between the service and sleeve must be sealed such that it is permanently gas tight and capable of accomodating movement. gas or water pipe or cable enters a building below ground, it must pass through a sleeve which is fixed into the wall. It is possible for gas to escape from buried gas pipes in the surrounding soil - this gas could diffuse to the surface and disperse harmlessly : alternatively, it could travel along the trench and enter via ducts or unsealed service entries into buildings posing an explosion risk.
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Densoseal 16A mastic conforms to British Telecom specification M212C for sealing cable ducts, conduits and service entry pipes or sleeves particularly below ground level to prevent entry of gas or water into buildings.ĭenso : Sealing of Service Entries & Ducts, Protection of Gas Escape and Water Ingress in Ducts & Service Entries Densoseal 16A duct seal is packed into the ends of the duct by hand and moulded firmly around cables and against the duct to close any gaps or fissures.ĭensoseal 16A is a non-setting self supporting mastic which may be applied to wet surfaces to seal ducts and conduits against ingress of gas and water. British Telecom (BT) & British Gas Approved Duct Sealsĭenso Mastic - Densoseal 16A Service Entry & Duct Seal Systemĭensoseal 16A duct seal systems is a firm fibrous mastic based on mineral fillers, organic fibres and water displacing materials.