Cottonsafe® – safe from chemicals, safe from fire
Flame retardants in UK furniture increase smoke toxicity more than they reduce fire growth rate
This recently published scientific research by the University of Central Lancaster and Manchester fire brigade reports that:
“fire toxicity is the main cause of death and injury in fires, and that upholstery and bedding fires cause a disproportionate number of fatalities, yet there is no requirement to assess the toxicity of burning domestic furniture. This has led to an over-reliance on chemical additives (flame retardants) to meet the UK’s furniture flammability regulations. It is evident that once the ignition occurs, the presence of flame retardants has little effect on the fire growth rate, but does have an adverse effect on the smoke toxicity.”
The research study, led by Prof Richard Hull, Professor of Chemistry and Fire Science at Central Lancaster University, and published in Chemosphere, an international journal for environmental chemistry and engineering, compared toxic emissions from a range of widely available mattress fabrics containing fire retardants with a leading brand of chemical free mattress fabric, Cottonsafe®.
< This graph shows concentrations of carbon monoxide:
- Fire retardant treated fabric reaches maximum carbon monoxide output in approximately 10 minutes of burn.
- Cottonsafe® (in green) has a considerably lower output.
> This graph shows concentrations of hydrogen cyanide:
- Fire retardant treated fabric reaches maximum hydrogen cyanide output in approximately 10 minutes of burn.
- Cottonsafe® (in green) stays very low until 30 minutes after burn providing a much longer escape time.
< This graph shows the time to reach lethal concentration (assuming 30 minutes exposure in 500 m³):
- Fire retardant treated fabric reach this limit in approximately 10 minutes.
- Cottonsafe® Chemical free fabric doesn’t reach the lethal concentration until 66 minutes after burn.
> The research shows the time to incapacitation in 150m³
- Fabrics treated with retardants produce substantially greater amounts of highly toxic Carbon Monoxide and Hydrogen Cyanide compared to the Cottonsafe chemical free mattress fabric.
- Time to lethal concentration is approximately 10 minutes for flame retardant treated mattresses, compared to more than 60 minutes for the Cottonsafe® chemical free mattress.
The study concluded that:
“Assessment of the effluents’ potential to incapacitate and kill is provided showing the two UK constructed flame retardant sofa-beds to be the most dangerous, followed by the sofa-bed made with European materials. The UK sofa-bed made only from natural materials, (Cottonsafe®) burnt very slowly and produced very low concentrations of toxic gases”.
Regarding the use of flame retardants in general the researchers go on to say:
“Reports in the literature show that the UK has the highest levels of flame retardants in household dust in the world (44) which are probably released from upholstered furniture and bedding during its lifetime, negating any potential fire safety benefit from the furniture flammability regulations, while causing problems of endocrine disruption (such as developmental disorders, difficulty in becoming pregnant, and obesity) from inhalation or ingestion of the contaminated dust.”
They also suggest that “including fire toxicity in the Fire Flammability Regulations would reduce the chemical flame retardants and improve fire safety.”Acknowledgements
“One of us (RB) would like to thank Greater Manchester Fire and Rescue Service for provision of a studentship. One of us (RGW) would like to thank West Midlands Fire Service for provision of a studentship. We would all like to thank Mark Dowen of Cottonsafe® Natural Mattress for provision of samples, help and advice, and Lancashire Fire and Rescue Service for provision of test facilities at their Washington Hall training centre.”44 – Kuang, J., Ma, Y., Harrad, S., Concentrations of “legacy” and novel brominated flame retardants in matched samples of UK kitchen and living room/bedroom dust, (2016) Chemosphere, 149, 224-230.