ABSTRACT
Nature of Ultraviolet Radiation 828
Quantities and Units 829
Radiometric Calculations 829
The Standard Erythema Dose 830
Detection of UV Radiation 830
Dosimetry of UV Radiation 831
Spectroradiometry 831
Components of a Spectroradiometer 832
Input Optics 832
Monochromator 832
Detector 833
Calibration 833
Sources of Error in Spectroradiometry 833
Commercial Spectroradiometers 833
Broad-Band Radiometry 834
Spectral Sensitivity 834
Angular Response 834
Radiometers That Simulate Biological Action Spectra 835
Wavelength-Independent Radiometry 835
Radiometer Stability 835
Measuring Personal Exposure to UV Radiation 836
Physical Dosimeters 836
Chemical Dosimeters 836
Biological Dosimeters 836
Simulated Sources of Sunlight 837
Xenon Arc Lamps 837
Fluorescent Lamps 837
References 840
NATURE OF ULTRAVIOLET RADIATION
Ultraviolet (UV) radiation covers a small part of the electromagnetic spectrum.
Other regions of this spectrum include radiowaves, microwaves, infrared radiation
(heat), visible light, X-rays, and gamma radiation. The feature that characterizes
the properties of any particular region of the spectrum is the wavelength of the
radiation. UV radiation spans the wavelength region from 400 to 100 nanometers
(abbreviated to nm). Even in the UV portion of the spectrum the biological effects
of the radiation vary enormously with wavelength and for this reason the UV spec-
trum is further subdivided into three regions. The notion to divide the UV spectrum
into different spectral regions was first put forward at the Copenhagen meeting
of the Second International Congress on Light held during August 1932. It was
recommended that three spectral regions be defined as follows:
