3. The phosphorus distribution of the PFR additives in the condensed and in the gas, phase was determined by analysing the original compounds and the ashes from the compounds after pyrolyzing them in a muffle oven at 900 o C. The P content was determined using Inductively Coupled Plasma, ICP-SFMS according to SS EN ISO 17294-1, 2 (modified) and EPAmethod 200.8 (modified) standards. The double focusing (electric and magnetic) ICP-MS, also known as Sector Field (ICP-SFMS), was employed to achieve high detection sensitivity and low background interference.