Dan Middleton Technical Officer at the BMC writes,
"This is one of the things we tried to achieve with the BMC Know Your Stuff conference, which was sold out and was very well received by those who attended. One of the sessions looked at the strength of worn and damaged tape webbing, showing that abrasion can be much worse (whilst looking less serious) than a cut. One really useful source of information is the Petzl website, they've always been good when it comes to information supplied with their products and in their catalogue but this goes to another level. There is a whole section devoted to inspection of equipment, with movie clips, downloadable inspection forms, and examples of different kinds of damage and how to deal with them. "
Dan gave us this link at the Petzl website. Click on 'harnesses' and witness a short clip on how to inspect your harness.