Malhotra, H.L., 1956. FURTHER EXPERIMENTS ON THE TRANSMISSION OF HEAT FROM FLUE PIPES. Fire Research Notes 243
Some experiments have been carried out to determine the effect of providing a metal sleeve round a flue pipe where it passed through, a brick wall and filling the gap between the pipe and the sleeve with asbestos rope, There was a significant reduction in the heat transmission as measured by the temperature rise of a timber wall plate compared with the results obtained when no sleeve was used. Some tests were also performed to find the effect of interposing a noncombustible shield between the ceiling of a timber joist floor and a horizontal flue pipe. The use of a metal shield led to a reduction of the temperature of the ceiling and the joists.