The Welsh soul singer said her life “flashed before her eyes” when the incident happened as she was about to play a support slot for the band in Ohio last month.
She added: “The entire left side of my hair went up in flames. At that moment, Chris was walking down the corridor to say ‘hi’.
“I hadn’t met him before and the place stank of burning hair.
“Can you imagine if I had gone up in flames? Nightmare. I honestly saw my life flash before my eyes.”
Her latest single, ‘Rain On Your Parade’, is released on November 17.