Supplement to the code of practice for clinical proton dosimetry. ECHED (European Clinical Heavy Particle Dosimetry Group).

The 'Code of Practice for Clinical Proton Dosimetry' (Vynckier, S., Bonnett, D.E. and Jones, D.T.L. Code of practice for clinical proton dosimetry. Radiother. Oncol. 20: 53-63, 1991) was published in 1991, but since then new data for mass stopping powers have been reported and consideration has been given to the specification of absorbed dose in water instead of the original recommendation of absorbed dose in tissue. This supplement summarises the basic recommendations of the original Code of Practice and incorporates the new stopping power data for dose specification in water.