shazapple wrote:I think it's an excellent tool... when used properly, which includes thinking about what happens after you fall. You can't assume you or your helper can save you and you can't assume the fire department can get there in time. You need a rescue plan that consists of trained people and expensive equipment, which i think are out of the realm of the average DIYer. Even most roofing companies avoid harnesses in favour of simpler methods.
The best method to protect yourself from falling is proper setup and use of scaffolding or ladders. Good guardrails and planks for your scaffolding that is anchored to the building. Proper setup for your ladder; 1:4 slope, solid ground, both rails supported, 3 rungs above the supporting surface, tied off at the top (I've seem people use locking pliers on metal flashing and tied to the ladder to stop it from sliding). Keep your weight between the rails, 3 points of contact when you are ascending/descending, keep your boots and ladder clean. Finally, buy a decent grade 1 or 2 aluminum ladder, not the grade 3 home depot special.
I agree with most everything Shazapple wrote. But even with proper setup and use of scaffolding and ladders, accidents happen. Bad accidents. Often, these accidents happen to people who were 100% certain that they had set everything up properly, even if if they were later revealed to have been mistaken. OSHA is satisfied by either "fall prevention" systems (guard rails, safety nets, safety belts etc) or "fall arrest" systems (body harness and anchors). On a fixed ladder, over 24 feet, one or more of these methods must be employed. On a portable ladder, this is not required.
That said, for me, some thought needs to be given to "what would happen if I fell from here" even if OSHA does not require it. If the answer is "certain death", then, for me, I'd rather be wearing a harness and take my chances with the dangling. I used to be an avid climber back in my late teens and early 20's, and I've had my share of fall arrests - some significantly higher then the drop you'd be likely to encounter with a properly used fall arrest system. So I look at it like this: Seat belts, even when used properly, can cause injuries. Still, I buckle up every single time, because I'd rather take my chances with an injury from the belt then be ejected from the car. So too, I'd rather have airbags, even if in some cases, I run a risk of being injured by them. The same necessary evaluation is true for the use (or not) of a harness, IMO.
here are some potentially useful links:
http://www.worksafebc.com/publications/ ... ection.pdfhttp://www.osha.gov/pls/oshaweb/owadisp ... p_id=23870http://www.oseh.umich.edu/pdf/guideline/guidslfp.pdfhttp://www.osha.gov/SLTC/etools/constru ... rrest.htmlhttp://www.orosha.org/pdf/pubs/2824ce.pdfChris
http://www.saracenihouse.com