Microbiology & sterility
Laminar air flow unit (LAF)
A work station that blows HEPA-filtered air in a uniform, one-directional stream over the work surface to give an ISO 5 / Grade A zone for aseptic handling of media, samples and sterile materials.
- Pharmaceutical
- Biotech
- Hospitals and compounding pharmacies
- Electronics
- Food & beverage
- Research laboratories
PREVENTIVE MAINTENANCE
Maintenance checklist
Daily / each use
- Clean and disinfect the work surface and walls
- Record differential pressure across the HEPA filter
- Record UV lamp usage hours (if fitted)
Weekly / monthly
- Clean the exterior and the front grille
- Inspect or replace the pre-filter
- Check lights and alarms
Six-monthly
- Air velocity measurement
- Non-viable particle count (classification)
- HEPA filter integrity test (some sites test annually)
- UV lamp intensity check, replacing the lamp if below the SOP limit
As needed
- Replace the HEPA filter when damaged, when it fails integrity testing, or when pressure drop shows it is loaded
- Re-qualify after filter replacement, relocation or major repair
SAFETY
Safety precautions
Before you work on the LAF
- An LAF protects the product, not the operator. Handle pathogens, toxic or sensitising material only in a biosafety cabinet.
- UV lamps can burn eyes and skin. Keep the sash closed and stay away when the lamp is on; interlocks should switch it off when the blower or lights are switched on.
- Do not use open flames in the LAF: they disturb airflow and can ignite alcohol vapour or damage the HEPA filter.
- Alcohol disinfectants are flammable. Let surfaces dry and do not spray towards the filter.
- Discard cultures and contaminated materials as biohazardous waste and decontaminate them by autoclaving.
In LimsPulse · Calibration Management
Keep every LAF in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.