Evacuate the room  immediately

Leave the BSC  operating and do not re-enter the room for at least four hours. This will provide  considerable dilution of the infectious droplet nuclei. Also, evacuation of the air through the HEPA filter system should reduce the potential of people outside the building becoming infected

Fog the room using a fogging machine and appropriate disinfectant. Allow the fog to settle

Decontaminate the BSC  using formaldehyde as described earlier