OSHA req'mnts for stair loading 2

[ELI07]

thread507-56989

I have the same question from this old thread with respect to the loading requirements for an industrial stair per OSHA which says "five times the normal live load anticipated but never of less strength than to carry safely a moving concentrated load of 1000 pounds"

I have always used 100 psf live for stairs, but do I have to use 5 times 100psf = 500psf, it seems a lot to me, and spread over the stair treads/platform? what about the 1000lb moving load, should I just apply it once at the worst location?

 

[Bagman2524]

no. The live load anticipated in OHSA is not 100 psf. It's the number of people you expect on the stair x their average weight.
check for 100 psf and 1000 lbs. and 5 x anticipated load all applied as independent loads and use the most severe load case.
There are several sections in 1910.23 & 24 that are easily misunderstood and need to be clarified by OSHA.

 

[ELI07]

thank you!!! I appreciate it a lot, will do that. Couldn't find any examples and it was hard to understand the OSHA requirement.

 

[Once20036]

Since OSHA doesn't weigh in on safety factors, allowable design stresses, etc, and these loads are well beyond what the design would typically necessitate - I check these criteria with a load factor = 1.0, the full fy of the material, and no deflection checks.

 

[boo1]

Fixed industrial stairs.1910.24(c)

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=standards&p_id=9716

"Stair strength." Fixed stairways shall be designed and constructed to carry a load of five times the normal live load anticipated but never of less strength than to carry safely a moving concentrated load of 1,000 pounds.

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=23731

 

[ELI07]

thank you all for your help.... this is an awesome forum!!!