While I don't know about the use of masks for DTT, one of the issues that occurs to me when removing it from a fume hood is the exposure to proximal colleagues or those walking by. Even if you are within a personal room, the fumes are also likely to linger for a given time after you have packed up and left.

Thanks Dr Williams for your reply. I can actually book the whole lab for only myself for the days that I need to work with DTT if it was necessary. Do you know if it would still be dangerous for others after one day if I do that?

I'm not sure what problems are presented by a fume hood. You can have walk-in ones as well as benchtop versions. If it is handling, then possibly a glove-box would be acceptable. In general, if something requires PPE for any reason, it is NOT a good idea to release it into any common areas.

Best regards,

Steven