Hi Sundus,

the use of a hood, independently of the type, has more to do with the culture of the lab you are in than to the necessity. I have worked many years doing PCRs in a regular lab bench an I never have problem with contaminations. I have also worked in labs where PCRs were always prepared in a laminar flow hood. Of course if you are working with potentially dangerous material, like when tittering viruses or with human blood, an extra barrier might be useful or even required.

Hope this helps,

Ezequiel

thanks Ezequiel. i also used laminar flow hood during my research. now i have to buy a safety cabinet for my own lab, where we do molecular biology  and isolation (organic chemistry) work in same lab for this i need both fume hood and laminar flow.  is its possible that class 2 fume hood will used for both?