The methods of surveillance of coronary angiography or angioplasty operators vary from team to team. The choice of method implies evaluation of the level of exposition of unprotected areas. The usual methods of surveillance by dosimetry may be complemented by an electronic device used for industrial radiological protection against X and Gamma rays. This instrument emits a sound each time a micro sievert is detected: the operator perceives the photons of diffused rays. The value of protective screens is then directly audible. This instrument does not detect X rays with an energy of less than 50 KeV but there is a good correlation with results measured by thermoluminescent dosimetry. The measurement of irradiation were noted at three points on the body before and after the use of complementary protection which certain operators hesitated to use before this study. The results confirmed the value of these protections: the suspended lead screen reduced cervical irradiations by a factor of 15 and that of the left wrist by 8. Lower down, a flexible lead skirt reduced irradiation of the ankle by a factor of 19. These results underestimate the efficacy of the screen as low energy X rays were not measured and are even more easily absorbed by the screens.