What does field certification involve?


Field certification consists of required tests related to containment (personnel, product and environmental protection), and optional tests related to worker comfort and safety.

Required tests include:

  • Airflow velocity profiles (downflow and inflow)*
  • Airflow smoke patterns*
  • HEPA/ULPA filter leak test*
  • Site installation assessment tests*
    • Alarm functions*
    • Blower interlock*
    • Exhaust system performance* (proper exhaust duct negative pressure and canopy performance)
  • Cabinet integrity test (positive plenum cabinets only)

Worker comfort and safety tests include:

  • Lighting intensity*
  • Vibration
  • Noise level*
  • Electrical leakage, ground circuit resistance*, and polarity*

*Part of LTS Standard Certification Report
In addition to the above NSF/ANSI 49 recommends the lifespan of a unit be 15 years. Starting at age 16 Lewis Testing Services requires a degradation inspection be performed to reduce the safety risks that an aging unit generates.