Abstract: A one component isocyanate prepolymer mixture for formulating a polyurethane product in a single step process, with monomeric methylene diphenyl diisocyanate (MDI) content in the mixture not exceeding 3%, preferably less than 2%, more preferably less than 1% of the total weight. The mixture contains monofunctional alcohol, an isocyanate component or isocyanate mixture component, propellant, catalyst, stabiliser, and one or more polyols. The monofunctional alcohol constitutes ethylene glycol ethers or propylene glycol ethers. A method for formulating a one component polyurethane foam on the basis of the mixture is disclosed.