How to Inspect the Exterior, 23.5 error.

[dtaylor6 (Darren Taylor)]

How to Inspect the Exterior, 23.5 states:

“For example, according to the psychrometric chart, air at 68º F (20º C) with 0.216 ounces of water (H2O) per pound of air (14.8g H2O ÷ kg air) has a 100% RH. The same air at 59º F (15º C) reaches 100% RH with only 0.156 ounces of water per pound of air (10.7g H2O ÷ kg air). The colder air holds about 28% of the moisture that the warmer air does.”

This isn’t quite right. The colder air holds 28% LESS moisture than the warm air. Not 28% of the warm air moisture. 28% of the arm air moisture would only be .06 ounces of water per pound of air.

[ktarasenko (Kate Tarasenko)]

Hi, Darren –

We’ll look into this and correct the course as needed – thanks for the heads-up!

[bgromicko (Ben J. Gromicko)]

@dtaylor6

How to Inspect the Exterior, 23.5 states:

“For example, according to the psychrometric chart, air at 68º F (20º C) with 0.216 ounces of water (H2O) per pound of air (14.8g H2O ÷ kg air) has a 100% RH. The same air at 59º F (15º C) reaches 100% RH with only 0.156 ounces of water per pound of air (10.7g H2O ÷ kg air). The colder air holds about 28% of the moisture that the warmer air does.”

This isn’t quite right. The colder air holds 28% LESS moisture than the warm air. Not 28% of the warm air moisture. 28% of the arm air moisture would only be .06 ounces of water per pound of air.

You’re correct, Darren.
156 divided by 216 equals 72%
We’ll fix the course.
We’ll send you a box of inspector goodies in the mail.
Thanks!