An intumescent thermoplastic elastomer molding composition is disclosed that includes high density polyethylene with chlorinated polyethylene and/or silicone rubber; a heat stabilizer for the thermoplastic elastomer material and an intumescent and fire-resistant additive for the thermoplastic elastomer, whereby moldings prepared from such mixture have good physical properties over a substantial range of ambient temperatures and display a resistance to flame and heat as characterized by the Intumescence Efficiency test of this specification.