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Matthew's avatar

Masks and Breathing Deeper:

Thank you for your comment!

Tidal volume increases in response to the obstruction of air flow, as each breath must be longer to pull in fresh air from outside the mask or respirator. It seems possible a person could actually be pulling unwanted pathogens further into their respiratory tract when wearing a mask or respirator.

The greater the "protection", the more it obstructs air flow and the longer and deeper breathing becomes.

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Harry's avatar

What fools mankind was to invent face masks. Firefighters, spray painters, take note of this wisdom.

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TB's avatar

There's a time and a place. When working around dust or particles (sanding, grinding, cutting) a mask will keep nasty crap out of your nose and mouth. Against smoke and viruses, not so much.

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Harry's avatar

The cat bases his evaluations on lots of data, so here's some for my mask (https://envomask.com/why-envo-mask/)

https://envomask.com/wp-content/uploads/2019/04/Filter-Penetration-Test-Report.pdf

Summary from page 3:

"Filter Test Procedure: Prior to testing, respirators were taken out of their packaging and placed in an

environment of 85 ± 5% reiative humidity (RH) and 38 ± 2,5°C for 25 ± 1 hours.

The filter tester used in testing was a TSI® CERTITEST® Model 8130 Automated Filter Tester that is

capable of efficiency measurements of up to 99.999%. It produces a particle size distribution with a count

median diameter of 0.075 ± 0.020 microns (pm) and a geometric standard deviation not exceeding

1,86 pm. The mass median diameter was approximately 0.26 pm, which is generally accepted as the

most penetrating aerosol size. The reservoir was filled with a 2% NaCI solution and the instrument

allowed a minimum warm-up time of 30 minutes. The main regulator pressure was set to 75 ± 5 pounds

per square inch (psi). The filter holder regulator pressure was set to approximately 35 psi. The NaCI

aerosol generator pressure was set to approximately 30 psi and the make-up airflow rate was set to

approximately 70 liters per minute (L/min).

The NaCI concentration of the test aerosol was determined in mg/m^ by a gravimetric method prior to the

load test assessment. An entire respirator was mounted in the sponsor-supplied test fixture, placed into

the filter holder, and the NaCI aerosol passed through the outside surface of the test article at a

continuous airflow rate of 85 ±4 L/min. In accordance with NIOSH policy, three respirators were

challenged until 200 ± 5 mg of NaCI had contacted each test article. Based upon the load pattern of

NIOSH Type 2, the initial penetration reading of the remaining 17 respirators was recorded"

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