What kind of travel path is this located along?

ADA will definitely come into play.

ADA will have nothing to do with it. It is in a process area of an industrial plant.

If you don't put stairs in people will be cussing you. 18" is too much for a traveled area.

Without regard to ADA, you have code-mandated egress requirements. As jgailla noted, 18" is too much for a traveled area. It is an obstruction and must be accommodated by steps or an opening to allow free movement.

Without regard to ADA, you have code-mandated egress requirements. As jgailla noted, 18" is too much for a traveled area. It is an obstruction and must be accommodated by steps or an opening to allow free movement.

Per OSHA "interpretations" this wall is not considered an obstruction until it reaches 4' tall. In other words, OSHA does not consider the 18" wall an egress impairment. Please understand that it is because they addressed this specific issue. Don't apply it to buildings and other situations. They just don't seem to have anything about stairs in the same area.

If people need access between the two areas, 18" is too large to be stepping up, and more importantly down. At 27 years old, I stepped down about 18" and came down on my knee too hard, I felt it for the next two weeks... If you're expecting people to do this on a regular basis, an injury is inevitable. It's not a matter of whether or not there is a specific code or OSHA requirement for steps, it's a matter of limiting your liability. One workers comp claim is going to be a lot more expensive than adding the steps.

I am not sure why you would assume the process area of an industrial plant is exempt from ADA requirements.


303 Changes in Level
303.1 General. Where changes in level are permitted in floor or ground surfaces, they shall comply with 303.

EXCEPTIONS:

1. Animal containment areas shall not be required to comply with 303.

2. Areas of sport activity shall not be required to comply with 303.

303.2 Vertical. Changes in level of 1/4 inch (6.4 mm) high maximum shall be permitted to be vertical.

@Twinkie,
ADA requirements only apply where a disabled person is likely to go. Where hazardous chemicals are present, an accident can cause a healthy individual to crawl on their hands and knees just to get to a safety shower. How would a wheelchair bound person get to the safety shower when one or both of their arms are impaired through chemical damage and they have no use of their legs? For reasons such as this, the disabled are not allowed into such hazardous areas.

If you've never been in a heavy industrial plant, you won't understand.

@ameyer...
The 18" height is not a step up/step down situation. This is simply: raise your leg and step onto the other side, then raise your other leg to step onto the other side, then proceed. I'm looking for something analogous to a retaining wall vs. knee wall vs. curb. Yes, a knee wall retains earth. But the forces are simply too small to really worry about it even if it falls. And a concrete curb may not fall over even if the concrete completely breaks off at the bottom.

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What I seem to be getting is that no one has heard of any such standard that addresses this condition. Is that correct?

Why not just put a step on each side of the wall and be done with it? You don't need a code, just common sense.

What is the width of the barrier?

If this is just a simple barrier (ie secondary containment) that has a width of a standard curb (4 inches), then you probably don't need a step. And I doubt you would find a standard / specification / regulation addressing this specific need. I'm also assuming that the only people walking into this area have direct business in there & those that do not can easily move around the area (or would not use it as a short-cut).

If the barrier's width is larger such that someone would be likely to step on top of the barrier, then put in a step. I don't know of any regulations addressing this need, either, although I'm sure there is one somewhere.