BMBL Appendix A - Table 1 Comparison of Biological Safety Cabinets

BMBL Appendix A - Table 1 Comparison of Biological Safety Cabinets Biosafety in Biomedical and Microbiological Laboratories

BMBL Appendix A - Table 1

Comparison of Biological Safety Cabinets

Type	Face velocity (lfpm)	Airflow Pattern	Radionuclides/ Toxic Chemicals	Biosafety Level(s)	Product Protection
Class I * open front	75	In at front; rear and top through HEPA filter	No	2,3	No
Class II Type A	75	70% recirculated through HEPA; exhaust through HEPA	No	2,3	Yes
Type B1	100	30% recirculated through HEPA; exhaust via HEPA and hard ducted	Yes (Low levels/volatility)	2,3	Yes
Type B2	100	No recirculation; total exhaust via HEPA and hard ducted	Yes	2,3	Yes
Type B3	100	Same as IIA, but plena under negative pressure to room and exhaust air is ducted	Yes	2,3	Yes
Class III	NA	Supply air inlets and exhaust through 2 HEPA filters	Yes	3,4	Yes

* Glove panels may be added and will increase face velocity to 150 lfpm; gloves may be added with an inlet air pressure release that will allow work with chemicals/radionuclides.

BMBL Table of Contents

CDC Home Page

NIH Home Page

This page last reviewed: June 17, 1999

For information about this site, please contact DS Web Coordinator, KH21K@nih.gov
National Institutes of Health Bethesda, MD 20892