More of these signs are popping up all the time, around Boise. This one is about 48 hours old; they installed it in a public parking lot across the street from my house.
When another sign up the road says Regular Unleaded is $2.799, is this sign really needed? (Why would a motorist not turn off his engine? Gotta keep that A/C blowing?)
And, how far does the clean air extend? Will these "clean air zones" eventually be placed close enough together that I can take a deep breath and dash for the nearest one, to grab another breath of clean air?