chapter  41
16 Pages

Dosimetry of Ultraviolet Radiation: An Update

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: