This article, presents a pretty good argument in favor of not allowing gas in a BSC. Many companies utilize gas in the BSC (Biological Safety Cabinet) to sterilize their loops. As consultants we need to bring these potential issues up to our clients when discussing how they will be using the BSC.
• The flame creates turbulence in the laminar flow of air minimizing product protection.
• Heat could melt HEPA filter bonding agents which destroys the filters effectiveness and loss of containment.
• If flame goes out gas will be distributed into the space possibly reaching explosive limits. ( use of an class II -A2 70% recirculation)
The BMBL states open flames are not required in the near microbe- free environment of a BSC and that touch plate micro burners could be used minimizing turbulence and heat buildup.
The CDC states if a flame is necessary there are products that are safer than the Bunsen burner. Attached is one of these and check out the video link on how it works.