fixed ladder attached to steel tanks 1

[bhart192]

we have a number of tanks at out facility,these were installed some time ago , we want to make sure we're ok with OSHA I see rules for fixed ladder in 1910.27 which seems to address platforms do these same rules apply to tank tops

 

[JStephen]

A short history on some of this:
Long ago, OSHA had their General Industry ladder, stairway, and handrail standards. These were based on ANSI standards. The ANSI standards were updated and changed, the corresponding OSHA requirements were not.
About 20 years ago, OSHA published a proposed revised rule governing all of this. The proposed rule never was actually enacted, but, OSHA has stated that compliance with the proposed rule was a "de minimis" violation that won't be cited, etc.
Several years later, they republished a proposed revised rule. Once again, it never has actually been adopted.
The result is that right now, if you go to the OSHA website and look up the "OSHA Laws and Regulations", you get the "old" rule as currently in the CFR. But if you look up OSHA Publication 3124, you get the "new" rule, based on the proposed revisions, which conflicts with the old. So in effect, there are two different conflicting rules out there.

With that background, here is an interpretation issued a number of years ago on the issue:

https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=INTERPRETATIONS&p_id=25100

With the latest revision of the "proposed" rules, a tank roof could either be a walking/working surface or could be treated like the roof on a building, depending on how often it was accessed.
MY interpretation is that if it's a walking/working surface, it should be enclosed by handrails (not just having handrails close to the ladder), but this seems to not be an issue with OSHA. Maybe they don't enforce that until somebody falls off.

 

[MJCronin]

Another possibility is to arrange tank roof nozzles so that a small shell mounted platform is located nearby, at the top of a ladder.

Nozzles such as vents and gauge hatches can be mounted at the edge of the shell allowing access, next to the small platform.

If the entire roof must be accessed, it would still be possible from the small platform.

The small platform concept will typically cost less than the cost of handrail around the entire edge of the roof.

http://www.thesaharian.com/education/fixed-and-floating-roof-storage-tanks/

MJCronin
Sr. Process Engineer