CHEMICAL CHIMNEY CLEANERS ANALYSED

Press, Volume CVI, Issue 31079, 7 June 1966, Page 18

CHEMICAL CHIMNEY CLEANERS ANALYSED

Do-it-yourself chimney cleaning with chemical chimney cleaners is not a complete answer to chimney problems and can be dangerous, the Consumers’ Institute has found.

As a result of complaints from members, it tested two types available in New Zealand.

One'was a mixture of sand and wood dust, sodium chloride and ammonium chloride, with a small amount of zinc oxide and copper chloride, which is designed to lower the ignition temperature of soot.

A laboratory report commented that it appeared “rather an innocuous preparation which would make a pretty green display. It is not understood how it could disperse soot, although it might have some effect in moderating or possibly stopping a small chimney fire.”

The other- chemical chimney cleaner was vigorous and slightly explosive, using oxidising chemicals to produce a fairly fierce fire and burn off soot deposits. Moderating agents are usually added to control the reaction, but the degree of control is problematical, says the institute. A chimney fire can cause showers of sparks and burning

soot and building fires have resulted when the flue has been defective. The cleaner had sodium chloride (common salt) and sodium nitrate roughly mixed with sawdust. There could be some danger if a whole packet were put in a bright hot fire, commented the testing laboratory. “It could give a big blaze, which could remove some soot from the chimney but could be dangerous and could set soot alight.” U.S. Report The American National Bureau of Standards has said that any chemical means of dispersing soot is of uncertain value. In the light of the laboratory test and the comments of the New Zealand Fire Service Council on the efficiency of chemical chimney cleaners generally, “Consumer” does not recommend this method of chimney cleaning. “A chimney fire creates a risk of fire-spread to the building, often at a future date,” “Consumer” says. “Chimney fires may develop temperatures far in excess of those the chimney is designed to withstand. Even when confined to the flue, defects may develop and allow hot gases of a later fire to reach surrounding woodwork and ignite it.” “Consumer” supports the New Zealand Fire Service Council’s comment that the only safe and sure way of removing soot from a chimney is to have it cleaned mechanically. An experienced chimney sweep does an efficient job without mess and will check flues.