at the dupont european technical centre in geneva, they've developed a material that can withstand extremely of a material that bubbles when exposed to high heat, insulating the wearer. it has been proven that if your body temperature, the core temperature, raises above a certain level, you start doing the wrong decisions, it affects your brain function and that's exactly what you do not want to have happen for a firefighter. eventually he would not realise when he is in extreme danger or would realise it too late. you can feel how raised the surface is, these bubbles, for want of a better word, have kind of lifted off the fabric compared to the bit that hasn't been exposed to the fire. naturally, these fabrics have to be vigorously tested and certified and, in the centre's own lab, they conduct a variety of burning tests to ensure the materials are robust. as a comparison, i looked at what happens when the same tests are conducted on regular cotton. the result was rather terrifying. my goodness. i mean, it's completely on fire. yes. it's burned through. they've also developed a smart heat—s