Condenser Ionization Chamber Built by Carl Braestrup for Measuring X-ray Emissions from Television Sets
The two condenser ion chambers shown here were
constructed for Carl Braestrup and Richard Mooney at
Instruments donated by Richard Mooney
At the time of the study, the International Commission on Radiological Protection (ICRP) recommended that the exposure rate on any accessible surface of a television set be limited to 2.1 mR/hr. As a result of their measurements, Braestrup and Mooney concluded (1959) that ďa permissible radiation level of 0.5 mr per hour 5 cm from any accessible surface of the equipment [a value under consideration] appears reasonable and will not require any changes in most existing sets.Ē This recommendation was later adopted by the NCRP and ICRP and it became the regulatory limit currently specified in 21 CFR 1020.10 by the FDA.
It was a lawsuit that first alerted the authorities to the potential emission of x-rays from television sets (CRTs).
After assembling a television set that came in the form of a kit, a gentleman suffered skin damage to his hands and face. When his doctor indicated that the damage appeared to be a radiation burn, the matter was taken to court. Unfortunately for the plaintiff, Braestrup testified that the x-ray output from the television had been too low to produce the observed skin damage. The latter turned out to be an allergic reaction to the soldering flux used in assembling the kit (Carl Braestrup. BRH Vignettes of Early Radiation Workers).
B. Braestrup (1897 Ė 1982) was born in
Braestrup, C. B., and Mooney, R. T. X-ray Emission from Television
Sets, Science 130: 1071-1074, Oct. 23, 1959.
Braestrup, C. B., and Mooney, R. T. X-ray Emission from Television Sets, Science 130: 1071-1074, Oct. 23, 1959.
Copyright 1999, Oak Ridge Associated Universities