I run most of the indexing for our company. I was curious about the coefficient of friction. The machine gives the gap in MM and " and the coefficient of friction. How is this number configured? And what range is acceptable? I have had guys to tell me to spray the skirts with silicone but if this is a friction test that seems to be defeating the purpose of the test. I look for the gap to be below 5mm. I haven't had a inspector fail any of my units but I'm just curious.

the A17.1-2004-8.11.4.2.19 edition of the code came up with the requirement for escalator, step/skirt performance index. The reason inspectors pass your units is they probably don't know what is a pass and what is a fail. The index is derived through a complicated engineering formula located in the A17.1 code book. As for the Gap, and co-efficient,it depends on the age and makeup of the Skirt material. 1955 thru 1970; 3/16in with both sides not exceeding 1/4in.1971 thru 1979;3/8in on each side.1980 thru 1999;3/16in on each side.2000 and later .2in(5mm). The Skirt material tells you whether to spray or not. If the Skirts are made of low friction material you do not spray silicone, those skirts made before 1982 should be sprayed, and after 1982 spray if they are not made of low friction material such as stainless or enamel. YIKES it is a Mechanics nightmare. When in doubt ask the Boss man.

Thanks for the info John. Asking the bossman isn't much help in my situation. Bossman calls me and asks these questions. All he wants is good numbers for them to pass. I don't mind running indexing on overtime but now I get pulled off my resident job and sent to run the annuals on the escalators on straight time. My job is labor intensive being that its a level 1 trauma center with old equipment and tons of traffic. As we all know when someone comes to cover they only answer calls and I show up the next day with multiple units lo/to. ***rant over**

Been there,done that. Hospital was low bid, which means not enough money to have a second Mechanic, or a Maintenance Helper. The equipment was run to death 24/7. I feel your pain Brother.

Speaking of skirt panels, does anyone know of a company that resurfaces them, when they no longer pass the indexing.