Low-Pressure (LP) UV:

  • Emits a single wavelength (253.7 nm).
  • Produces less UV light overall, requiring more lamps in the system for effective coverage.
  • LP Lamps operate at lower temperatures and therefore each LP lamp is more energy-efficient than an MP lamp.
  • Limited versatility in handling a variety of contaminants, as it does not damage microorganisms’ recovery mechanisms.

Medium-Pressure (MP) UV:

  • Emits a broad UV spectrum (200-415 nm), covering a wider germicidal range.
  • Damages both the DNA and repair mechanisms of microorganisms, achieving superior disinfection.
  • Effective across a wide range of contaminants and complex organisms, including viruses and biofilms, which LP UV struggles to inactivate.
  • Unlike LP lamps, MP lamps operate also at higher temperatures with higher UV intensity per lamp, requiring fewer lamps in the system for equivalent coverage.

Key Differences:

  • Research indicates that MP UV is often superior for applications needing comprehensive inactivation of complex organisms, including viruses and biofilms, due to its broader spectrum and higher intensity.
  • MP UV is generally preferred for complex applications, such as Advanced Oxidation Processes (AOP), where wavelengths beyond 254 nm are required for optimal disinfection.