1 Introduction.- 1. Solar Ultraviolet Radiation.- 1.1 Introduction.- 1.2 Electromagnetic Radiation.- 1.3 UV Wavebands.- 1.4 Radiometric Units.- 1.5 Solar UV.- 1.6 UV Index.- 2. Atmospheric Ozone and Aerosols.- 2.1 Ozone.- 2.2 Scattering Processes.- 3. Solar Zenith Angle.- 4. Earth’s Orbit.- 5. Surface Albedo.- 6. Altitude.- 7. Summary.- 2 Diffuse Ambient Solar UV.- 1. Introduction.- 2. Diffuse UV Spectral Irradiances.- 2.1 Diffuse UV.- 2.2 Spectral Measurement.- 2.3 Spectra.- 2.4 Biologically Damaging UV.- 3. Summary.- 3 Personal Solar UV Exposures in Diffuse UV Settings.- 1. Introduction.- 2. UV in Tree Shade.- 2.1 Global UV in Tree Shade.- 2.2 Diffuse Irradiances in Tree Shade.- 3. Personal UV Exposure Distribution.- 3.1 Polysulphone Dosimeters.- 3.2 Personal UV Exposures in Tree Shade.- 4. Summary.- 4 Influence of Clouds on Solar UV.- 1. Introduction.- 2. Cloud Detection.- 2.1 Introduction.- 2.2 Satellite-based.- 2.3 Ground-based.- 2.4 Case Study.- 3. UV and Cloud Studies.- 3.1 Introduction.- 3.2 Inferred Cloud Detection.- 3.3 Direct Cloud Detection.- 3.4 Spectral Dependency.- 4. Summary.- 5 UV Enhancement by Cloud.- 1. Introduction.- 2. Literature Review.- 2.1 Overview.- 2.2 UVA Case study.- 3. UVB Enhancement.- 3.1 UVB Case Study.- 3.2 Postulated Mechanism.- 4. Spectral Dependency Revisited.- 5. Summary.- 6 Glass Filtered Solar UV.- 1. Introduction.- 2. Glass Transmitted UV Spectrum.- 2.1 Standard Window Glass.- 2.2 Automobile Window Glass.- 2.3 Special Types of Glasses.- 3. Filtered UV in a Greenhouse: Case Study.- 3.1 Spectral Transmission.- 3.2 UVA Irradiances.- 3.3 Erythemal UV Irradiances.- 3.4 Six Hour Erythemal Exposures.- 4. Summary.- 7 Solar UV in Automobiles: Ambient and Personal Exposures.- 1. Introduction.- 2. UV Radiation in Automobiles.- 2.1 UV Radiation in Automobiles: An Overview.- 3. Measurement of UV in Automobiles.- 3.1 Experimental Design: Laboratory vs. Field Based.- 3.2 Broad Band Filtered UV in an Automobile.- 3.3 Spectral UV Irradiances in an Automobile.- 4. Annual UVA Exposure in an Automobile.- 4.1 Estimates of Long-term UVA.- 4.2 Estimates of Seasonal UVA.- 4.3 Estimates of Annual UVA.- 4.4 Personal Ultraviolet-A Exposure in an Automobile.- 5. Summary.- References.