UVGI Lamps and Fixtures

Abstract

The ultraviolet (UV) lamp is the most critical component of any UVGI air or surface disinfection system. UV lamps come in many shapes, sizes, and UV output power levels, and they may produce different spectral bands of germicidal UV. All germicidal UV lamps will produce light wavelengths of either UVC (100--280 nm), UVB (280--320 nm), or both (UVC/UVB). Wavelengths of UVA (320--400 nm) are not germicidal and UVA lamps (i.e. blacklight and sunlamps) are not considered UVGI lamps and are not addressed in this chapter. UVGI lamps are commonly referred to as UV lamps and these terms are used interchangeably throughout this book. Various types of UV lamps are currently in use for air and surface disinfection applications, including standard medium pressure (MP) UV lamps which produce broadband UVC/UVB wavelengths, low pressure (LP) UV lamps that produce narrow band UVC wavelengths, microwave UV lamps, and light-emitting diodes (LEDs). Technically, UVC lamps are LP lamps that produce UVC wavelengths only, and the term is not necessarily accurate when applied to MP lamps that produce broadband UVC/UVB wavelengths although common usage doesn't always make this distinction.