u/Gumart1

I cut the drywall in the basement ceiling of my 1968 built house with a sawzall to access/fix a rattling duct. Little did I know I was also cutting deep into these ceiling tiles. Guessing from the looks that these were installed between 1968 and the mid-seventies. In the pic of the vent cut-out, I'm thinking that may be the mastic used to glue those tiles. Wore an N95 mask but know that's not enough and also, my entire basement is covered in a fine dust layer. If it can get any worse, my basement is open to the first floor. I haven't run the HVAC for 24 hours but I'll need to soon. I just sealed the only basement return vent with plastic. Am I cooked? Will be sending out a sample for testing tomorrow.