Abstract

The ISO/TS 19700 steady state tube furnace is a bench-scale method for assessing smoke toxicity of materials. It allows the ventilation conditions to be controlled during the test, allowing the toxicity of each fire stage to be assessed. Currently, the scope of ISO/TS 19700 limits its application to testing of “homogeneous thermoplastics”. This work investigates extensions to its use to more complex commercial products (plasterboard, energy cable, wood-based boards and flexible polyurethane foam). In order to achieve results representative of specific fire stages, certain extensions to the protocol were made. These include adjusting feed rate of the sample; adjusting the mass load; increasing the ventilation of preliminary runs; and provision for reporting data for flaming fire stages for essentially non-combustible samples. The products were tested in smouldering; and well-ventilated, small under-ventilated and large (post-flashover) under-ventilated flaming conditions, as defined in ISO 19706. With these adjustments it was found that the steady state tube furnace was able to assess the toxic product yields of more complex products, of unknown composition.