CHAPTER 4 



Technique of Study of Biological Effects 

 of Ultraviolet Radiation 



Jesse F. Scott* 



Department of Biologij, Massachusetts Institute of Technology 



Cambridge, Massachusetts 



and 



Massachusetts General Hospital 



Boston, Massachusetts 



Robert L. Sinsheimer 



Department of Physics, Iowa State College 

 Ames, Iowa 



Introduction. Sources: Classification of light sources — Physical parameters of sources 

 — Choice of a source — Practical aspects. Detectors of ultraviolet radiations: Fluorescent 

 screens — Thermal detectors — Photochemical detectors — Photographic detectors — Photoelec- 

 tric detectors. Methods of spectral isolation: Filters — Dispersing systems. References. 



INTRODUCTION 



The technique of the study of the effects of any radiation on Hving 

 systems is divisible, on an operational basis, into (1) the means of produc- 

 ing the radiation, (2) the means of manipulating and estimating the vari- 

 ous parameters of the radiation, and (3) the means of demonstrating and 

 analyzing the effects of the radiation on the biological system under 

 study. This operational outline will be adhered to in a discussion of 

 sources of ultraviolet radiation, detectors of ultraviolet radiation, means 

 of spectral isolation, and accessor}^ optical components. The various 

 means of demonstrating and analyzing the effect of ultraviolet radiation 

 on the biological systems are considered in great detail elsewhere in this 

 volume and will not be taken up here. It must be emphasized that this 

 chapter will not deal with the detailed technique of any particular study 

 but will be concerned with materials for such an investigation. This 

 approach is dictated by the great variety of problems in this field. For 

 example, one investigator may be interested in the abiotic activity of the 



* A Scholar in Cancer Research of the American Cancer Society. 



1H» 



