The efficacy of some fire-retardent chemicals incorporated into Ghanaian timber
1972
Adamczak, B. E.
A comparative trial was made of five fire retardants, viz. (a) a 60 : 40 mixture of borax and boric acid; (b) a Na-silicate solution of 40 deg Be density (defined); (c) a 70 : 30 mixture of (b) and kaolin; (d) a 70 : 30 mixture of (b) and limestone; and (e) concentrated Na-silicate solution (applied after preliminary impregnation with Na silicate diluted with water in the ratio 1 : 1). The timbers treated (by procedures described) were Nauclea diderrichii, Khaya ivorensis, Chlorophora excelsa and Entandrophragma cylindricum. The results showed that: the efficacy of the fire retardants tested was directly related to the quantities used; (a) gave moderate fire resistance at 42-49 kg/m3 retention; two coatings of (b), (c) or (d) gave satisfactory protection; (e) was highly effective, and when used on external timber should resist severe weathering for 1-2 years; and N. diderrichii was the most and C. excelsa the least fire-resistant of the four timbers. It is concluded that (a) can be recommended as a fire retardant for interior use and (e) for external use, while (b), (c) and (d) are suitable where only temporary protection is required or where the protective coating can be renewed frequently.
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