Useful Tips

Laminar Airflow & Safety Cabinet Tips

Define your needs before purchasing

Vertical laminar flow cabinets look, at first glance, like a microbiological safety cabinet. There are very important differences concerning protection.

In a vertical laminar flow cabinet, sterile filtered air protects the samples and items in the chamber by showering them in the clean air. No air from the environment can contaminate them. The clean air can, however, pick up aerosols (solid or liquid air-borne particles) from the contents of the chamber. A proportion of the air then exits the chamber by the gap below the front window; the rest is recycled and filtered again, extending the life of the filter.

In a microbiological safety cabinet, the sterile filtered air protects the samples and items as above. None of the air exits by the front gap. Approximately two-thirds of the air is recycled and one-third is exhausted after being sterile filtered. It is the entry of replacement, external air through the front gap, drawn immediately down through the slots and around to the sterilizing filter, that creates a barrier that prevents the escape of air from the chamber and the entry of external air to the working area. So a microbiological safety cabinet protects the samples, the operator and the environment.

Good laboratory practice

Create a working sequence starting with initial components, samples and materials on one side of the cabinet and ending with the finished products on the other side of the cabinet. Keep the contents away from the front 20 cm of the work area.

Minimize contamination potential

Sterilize and remove all items and containers from the cabinet immediately the work has finished. Do not allow items and waste to build up in the cabinet.

Optimize operation

Set the cabinet to half speed and fit the closing panel when leaving the instrument for short periods, such as coffee and lunch breaks. The air will be recirculated and very little new air will enter the cabinet. When you want to restart work, reset the airflow to full speed and remove the closing panel. The cabinet will reach safe operating conditions in just a few minutes when the airflow stabilizes. Starting a stopped and open cabinet will require a wait of 15 minutes to reach the same conditions. The life of the filter will not be reduced by running at half speed, because the same filtered air will be recycled.

Some Useful Tips information provided is based on publicly available sources. NÜVE provides it in good faith ‘as is’ in a service to our customers, but cannot take responsibility for its use. We strongly recommend scientists to check this information elsewhere before using it.