the actual data on mask effectiveness

Steven Petty (B.S.Ch.E. M.S.Ch.E. M.B.A.), Industrial Hygiene & PPE expert, "goes through the actual data on mask effectiveness" during his senate testimony to New Hampshire (US) Health and Human Services (5th April 2022).

Xposted from Ivor Cummins' channel:

https://www.youtube.com/@IvorCumminsScience
https://www.youtube.com/watch?v=ZFjLFqESxY0

Ep 141 The Ultimate PPE Expert with Incredible Insights into Mask Science
11 May 2022

"Here is a document with references which he [Stephen Petty] and a team submitted to NIH and CDC:

https://thefatemperor.com/wp-content/uploads/2022/05/CDC-Response-Letter-February-22-2022-Correct-Walenski-Zip-Code-and-Dates.pdf