The use of these procedures regarding rules pertaining to nonroad engines or vehicles is mandated by section 307(d)(1)(R) of the Clean Air Act.
Section 307(d)(1)(R) of the Clean Air Act contains the procedures concerning the rules.
Section 307(d)(1)(R)  of the Clean Air Act contains no provisions concerning nonroad engines and vehicles.
There are two mothers talking to kids.
A boy was in a snowball fight.
The man is outdoors
dog is in the water.
The dog is doing activities outside.
the men are sitting on their back porch playing outside while their hair is blowing in the wind