2 ms·

Not a statistics expert by any measure (I'm sure many people here are) - but doesn't effect size play a role here: https://www.ncbi.nlm.nih.gov/pmc/articles/PM

Not a statistics expert by any measure (I'm sure many people here are) - but doesn't effect size play a role here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5878948/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5878948/ If N95 masks in a virus laden environment are akin to parachutes when falling from an airplane - that's great news. I'm super happy to be educated on this given my unbroken record of never having been indoor in 18+ months without one. Happy to know that it's been making an absolute difference.

323 5y ago
> Upgrading face masks to filtering face piece (FFP3) respirators for healthcare workers on covid-19 wards produced a dramatic reduction in hospital acquired SARS-CoV-2 infections, according to research carried out at Addenbrooke’s Hospital in Cambridge. > Once FFP3 respirators were introduced [as opposed to simple surgical masks], the number of cases attributed to exposure on covid-19 wards dropped dramatically—in fact, our model suggests that FFP3 respirators may have cut ward based infection to zero. https://www.bmj.com/content/373/bmj.n1663 https://www.bmj.com/content/373/bmj.n1663 FFP3 is a bit better than N95 (it's equivalent to N99). N95 masks came from industry, but there were no RCT studies there. People just noted that they obviously worked, through arguably one can easily feel that a saw dust mask works as opposed to one against viruses.
- ghshephard 5y ago
  I wonder if an N95 that's been tested to filter 99%+ is roughly equivalent to a FFP3? https://www.armbrustusa.com/pages/mask-testing?mask=-review https://www.armbrustusa.com/pages/mask-testing?mask=-review
  - 323 5y ago
    I've done extensive research on this subject, for coronavirus purposes N95 is equivalent to FFP3. The most important aspect is having head bands (as opposed to ear loops) to secure a tight fit. N95 typically have head bands. FFP2/KN95 (filtering equivalent to N95) typically don't, which is why FFP3 are sometimes preferred. There are also regulatory reasons to use FFP3. 3M also manufactures FFP3 masks. Not sure if they sell them outside EU though. https://www.amazon.co.uk/3M-9330-Aura-Unvalved-Respirator/dp/B00VAT74NG https://www.amazon.co.uk/3M-9330-Aura-Unvalved-Respirator/dp...

323 5y ago

> Upgrading face masks to filtering face piece (FFP3) respirators for healthcare workers on covid-19 wards produced a dramatic reduction in hospital acquired SARS-CoV-2 infections, according to research carried out at Addenbrooke’s Hospital in Cambridge. > Once FFP3 respirators were introduced [as opposed to simple surgical masks], the number of cases attributed to exposure on covid-19 wards dropped dramatically—in fact, our model suggests that FFP3 respirators may have cut ward based infection to zero. https://www.bmj.com/content/373/bmj.n1663 https://www.bmj.com/content/373/bmj.n1663 FFP3 is a bit better than N95 (it's equivalent to N99). N95 masks came from industry, but there were no RCT studies there. People just noted that they obviously worked, through arguably one can easily feel that a saw dust mask works as opposed to one against viruses.

ghshephard 5y ago
I wonder if an N95 that's been tested to filter 99%+ is roughly equivalent to a FFP3? https://www.armbrustusa.com/pages/mask-testing?mask=-review https://www.armbrustusa.com/pages/mask-testing?mask=-review
- 323 5y ago
  I've done extensive research on this subject, for coronavirus purposes N95 is equivalent to FFP3. The most important aspect is having head bands (as opposed to ear loops) to secure a tight fit. N95 typically have head bands. FFP2/KN95 (filtering equivalent to N95) typically don't, which is why FFP3 are sometimes preferred. There are also regulatory reasons to use FFP3. 3M also manufactures FFP3 masks. Not sure if they sell them outside EU though. https://www.amazon.co.uk/3M-9330-Aura-Unvalved-Respirator/dp/B00VAT74NG https://www.amazon.co.uk/3M-9330-Aura-Unvalved-Respirator/dp...