Appendix 6. Ventilated workstation and biosafety cabinet

Update: October 2023

6.1 Ventilated workstation

To ensure a safe work environment when natural or mechanical ventilation is not adequate, WHO recommends the use of a ventilated workstation (VWS) for procedures that do not generate significant amounts of aerosols:

• Preparation of sputum smear for microscopy
• Loading of Xpert cartridges

The VWS is a partially enclosed workspace from which air is drawn inward and exhausted outside of the laboratory.

It is intended to be placed on a work-bench. It can be made according to WHO instructions a Citation a. For more information, see: CDC, GLI, IUATLD A. Ventilated Workstation Manual for AFB Smear Microscopy. 2011.
https://www.stoptb.org/gli-ventilated-workstation-manual-afb-smear-microscopy .

6.2 Biosafety cabinet

WHO recommends the use of a biosafety cabinet (BSC) Class II A2 [1] Citation 1. World Health Organization. Tuberculosis laboratory biosafety manual. World Health Organization. Geneva, 2012.
https://www.who.int/publications/i/item/9789241504638 for procedures that may generate significant amounts of aerosols such as decontamination, homogenisation or centrifugation.

Class II A2 BSCs are also required for inoculation of culture media and any procedure requiring manipulation of highly concentrated mycobacteria (e.g. strain identification, drug susceptibility testing).

Installation, certification, monitoring and maintenance should be performed by qualified technicians.