Blower Door Depressurization and the Human Ear

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Permalink Reply by Sean Lintow Sr on August 24, 2012 at 5:30am

Here is a chart I did showing the pressures:

Unit to pascal	25 Pa	50 Pa	75 Pa
1 atmosphere = 101,325 Pa	0.000 247	0.000 49	0.000 74
1 bar = 100,000 Pa	0.000 25	0.000 50	0.000 75
1 PSI = 6,894.76 Pa	0.003 63	0.007 25	0.0108
1 in Hg = 3,386 Pa	0.007	0.015	0.022
1 in H2O = 249 Pa	0.10	0.20	0.30
1 mm Hg = 133 Pa	0.19	0.38	0.56
1 millibar = 100 Pa	0.25	0.50	0.75
1 PSF = 47.88 Pa	0.52	1.05	1.56

That is not enough to affect a baby (nor break window seals, etc...) but with that said I also would not want to do a blower door test with an infant or very small child in the house as one is not sure what containiments one might be pulling in, nor how healthy that infant is.

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Permalink Reply by Bud Poll on August 24, 2012 at 7:31am

I agree with Sean about "the other contaminants" and in general, whether they understand how slight 50pa is or not, that doesn't stop them from telling everyone you did bad.

But, here is another example of how small 50 pa really is.  When you drive to a higher elevation, you can feel your ears pop.  A change in elevation is understood to be associated with a change in pressure.  Walk from a basement to the second floor and you will experience about 50 pa decrease in pressure.  Walk back to the basement and it increases by the same.

Our manometers cannot see this shift in atmospheric pressure, their design does not allow it, but that is another thread.  But explaining to a home owner that the 50 pa is about the same as top to bottom of a 2-story house might help.

Atmospheric pressure near sea level decreases about 3.5 pa per foot you go up.

Bud

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Permalink Reply by Sean Lintow Sr on August 24, 2012 at 12:05pm

Nice point Bud & I might have to actually add that to the article assuming you don't mind

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Permalink Reply by Bud Poll on August 24, 2012 at 12:15pm

Not at all.

Bud

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