Feasibility study on addition of a colourant to commercially used fire-retardant formulations to enable visual distinguishability between treated and untreated mine support timber

[摘要] ENGLISH SUMMARY: The ability to visually distinguish between fire-retardanttreated and untreated mining support timber,treated with ammonium sulphate and ammonium phosphatesalts, is very difficult. In fact, once treated andallowed to dry for approximately three days, it visuallybecomes totally non-distinguishable from untreatedtimber.The project objective is to identify a suitable colourantwhich can be incorporated into the fire-retardantformulation which will enable visual distinction betweenfire-retardant treated and untreated mining timbersupport on a cost effective basis. The following aspectswere evaluated:- Compatability and stability within fire-retardantformulations.- Colour effectiveness and fastness.- Effect on combustion.The results showed that:* Three of the chemical colourants proved to becompatible and stable at two ranges of temperatures.Colourants were Acid Green, Bazazol Red 76Land Malachite Green.* Of the colourants evaluated, Malachite Green andBazazol Red 76L performed most satisfactorily overtwo exposure trials, i.e. controlled weather-o-meterand natural exposure. * All three colouration chemicals had no effect on thecombustibility of timber when included into thefire-retardant formulations.* The inclusion of a colourant into the fire-retardantcan be performed in such a manner that fire-retardanttreatment economy is hardly affected.* Large scale evaluations need to be performed toverify colour efficiency over time.

[发布机构] Stellenbosch University