Explain what is meant by permeability and describe how to interpret the permeability ratings of vapor retarders.
What will be an ideal response?
The permeability of vapor retarders is rated in perms, a measure of the rate of transfer of water vapor through a material. Vapor retarders have permeability ratings of 1.0 or lower. Materials with a perm rate of ( 1 to 10 perms) semi-permeable, and (>10 perms) permeable.
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When possible, set the shielding gas flow rate on GMA, GTA, and ____ welding processes at the lower end of the flow rate range to reduce the shielding gas cost.
A. FCA B. GFCI C. FOW D. EPA
Technician A says that multipulse injection can result in smoother engine operation. Technician B says that multipulse injection today can mean breaking up fuel injection into up to 7 events per cycle. Who is correct?
A. Technician A only B. Technician B only C. Both A and B D. Neither A nor B
The FFA ____________________ Career Development Event has students practicing application of the Soil Conservation Service classification system
Fill in the blank(s) with correct word
What units are most commonly used to measure large quantities of heat quantity in the United States?
A) Therms B) Degrees Fahrenheit C) Kilocalories D) Joules