Poly (ethylene terephthalate) (PET) multifilaments loaded with fire retardants were produced via melt spinning and textiles were manufactured using the latter. The fire retardance properties of the knitted fabrics were investigated showing an important decrease of heat released with presence of phosphorous-containing chemicals (Exolit OP950). Incorporation of POSS nanoparticles in PET-OP950 systems slightly decreases the fire properties of the material but acts as good smoke suppressor with release of low toxic fumes while combustion. (C) 2012 Elsevier Ltd. All rights reserved.