STATISTICAL STUDY OF RADIOACTIVITY IN WRIST WATCHES (in French)
A study was conducted of 684 Swiss-made watches, approximates 2 of each model, to find the level of radioactivity of their luminous dials. Four tests were made on each watch: measurement by a thin-window Geiger-Muller counter of BETA radiation; measurement of gamma radiation by means of a NaI-crystal scintillation counter, with a 5% error on highly radioactive watches and more on less active ones; measurement of dosage received from the outer back surface of the watch, by a dosimetric film technique, with plus or minus 30% precision; classification as legible in the dark or non-legible in the dark, made by an observer with watch 20 cm from eyes after 1/2-hr dark adaptation. The results were as follows: determination of the nature of radioactive element in watches showed that two contained Sr and all others Ra /sup 226/ amount of radioactivity, as the algebraic mean activity of ordinary watches not containing Sr/sup 90/, was 0.102 mu C of Ra/sup 226/, and the average of watches manafactured in Switzerland in 1960 was 0.092 mu C of Ra/sup 226/; the total dosage was 1 mrem/ hr, that absorbed by the wearer was 0.17 rem/wk at the wrist (cf. max allowable dose 1.5 rem/ wk), and 0.001 rem/wk at the eye lens (max allowable dose 0.1 rem/ wk). The calculated genetic dose for Switzerland is 75 mrem/generation (30 yr), or 2--3% of natural genetic dose. (BBB)
- Research Organization:
- Institut de Radiophysique Appliquee, Lausanne, Switzerland
- NSA Number:
- NSA-18-003612
- OSTI ID:
- 4132205
- Journal Information:
- J. Suisse Horl., Journal Name: J. Suisse Horl. Vol. Vol: Nos. 1-2
- Country of Publication:
- Country unknown/Code not available
- Language:
- French
Similar Records
THE EFFECT OF ENVIRONMENTAL RADIATION AND THE VALUE OF THE MAXIMAL PERMISSIBLE DOSE
THE RATIO OF THE RADIOACTIVITY OF LUMINOUS WATCH FACES AND CORRESPONDING GONAD DOSES