Hi all, I have a rather naive question to ask about the shutting down of a Class II safety cabinet.
After turning off the flow, the air takes substantial time to stabilised (may be due to old equipment),
and therefore, after shutting down the sash, the pressure still within the hood would pull the sash inwards and has the danger of creating cracks to the glass (it has happened once). So I was advised to leave a gap (~0.5cm) when shutting down the sash to prevent this from happening.
May I know if it is still safe to turn on UV afterwards and whether this practice is ok?