the fire department protocol:

来源: 于 2022-09-22 14:01:09 [博客] [旧帖] [给我悄悄话] 本文已被阅读：次

when you stand on a ladder, stretch out your arms to grab a rung, your body should not be leaning back. This is about a 2: 5 or 2:4 ratio. So from the base of the ladder to the gutter is about 23*sqrt(5^2+2^2) /5 etc.. = 24 or 25 ft. 

I never use extension ladder to the maximum...

Get a 32 footer.