Quantifying fire-retardant concentrations in fire-retardant treated wood

This project focuses on one of the most basic questions within the topic of fire retarded (FR) treated wood; “how we can actually measure the concentration of FR in wood specimens”, this seems like a trivial question, but is actually a significant issue, barrier to further research studies, and more wide spread usage of wood in the built environment. Currently, the most common method, and the method used by building material certification companies, manufacturers, and test labs, is to simply weigh the wood products/samples before FR impregnation and then after impregnation has been completed. The amount of weight gain is then attributed to the amount of FR imbued into the wood. This method has several issues in its usage. Firstly, it is a bulk measurement, and does not account in any way how the FR is dispersed through the wood cross section (i.e. how deep it penetrated the wood sample). This presents an issue in attempting to quantify or correlate FR concentration with fire performance even before these products come onto the market, as surface concentration will have the highest initial impact on the fire performance, however the surface concentration is not known using this measurement method. Other issues are also faced during the usage of the FR treated wood, as the current measurement method does not allow further monitoring of the FR treatments “health” or concentration levels after it has left the test lab or manufacturing facility, therefore its fire safety performance is basically unknown from this stage onwards, especially if used in facades which are subject to weathering which is known to affect FR treated wood (through leeching). This presents a significant issue in the fire safety of buildings and is a barrier to woods more widespread use due to fire safety requirements in countries building codes. This project aims to test new techniques to quantify the concentrations and penetration depths of FR in wood-based products for the built environment.