LimsPulse
Microbiology & sterility

Biosafety cabinet (microbiological safety cabinet)

A ventilated enclosure that protects the operator, the product and the room when handling microorganisms. HEPA-filtered downflow keeps the work clean, an inflow of room air at the front stops aerosols escaping, and the exhaust is HEPA-filtered before it leaves the cabinet.

  • Pharmaceutical
  • Biotech
  • Hospitals and clinical labs
  • Vaccine manufacture
  • Food & beverage
  • Research laboratories
Photo of a Biosafety cabinet (microbiological safety cabinet)
Photo: The wub, CC BY-SA 4.0 (cropped), via Wikimedia Commons
TROUBLESHOOTING

Common problems, causes and fixes

Airflow alarm sounds during work
Likely causes
  • • Sash raised above the working height
  • • Front grille blocked by arms or items
  • • HEPA filters loaded with dust
  • • Exhaust duct fan failure (ducted cabinets)
What to do
  • • Return the sash to the marked height
  • • Clear the grille
  • • Stop work, close cultures and call service if the alarm stays on
  • • Check the building exhaust system
Low inflow velocity at certification
Likely causes
  • • Exhaust filter loading
  • • Fan speed set too low
  • • Exhaust damper or duct partly closed
What to do
  • • Adjust the fan speed and re-balance by a certified engineer
  • • Replace the exhaust filter if adjustment is not enough
  • • Check the duct and damper settings
Smoke escapes from the front opening during the smoke test
Likely causes
  • • Inflow too low or downflow too high
  • • Air currents in the room from doors, vents or traffic
What to do
  • • Re-balance the cabinet
  • • Relocate the cabinet away from doors and supply vents
  • • Repeat the smoke and velocity tests
Leak found in HEPA filter scan
Likely causes
  • • Damaged filter media
  • • Gasket or seal leak
  • • Filter not seated correctly
What to do
  • • Repair within the allowed area or replace the filter
  • • Reseat the filter or replace the gasket
  • • Repeat the integrity test
Contamination on negative controls handled in the cabinet
Likely causes
  • • Poor disinfection
  • • Cluttered work area disturbing airflow
  • • Filter leak
  • • Poor aseptic technique
What to do
  • • Review the cleaning record and disinfectant
  • • Reduce items in the cabinet
  • • Check filter integrity
  • • Retrain the analyst
In LimsPulse · Calibration Management

Keep every BSC in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.

See how