How many steps make a flight?

[blugosi]

In a fully sprinklered building with MNS, I have a corridor a 125 cm wide corridor, with three steps in the middle, connecting two levels with a small elevation difference.

I am calculating the capacity at 0.15 inch (3.8 mm) per person.

Do the three steps require adjusting the capacity factor to 0.2 inch (5.1 mm) use for stairways?

If yes, I should replace the steps with a ramp.

Where do we stop counting steps as "means of egress components other than stairways" from IBC ed 2021, 1005.3.2 ?

 

[steveray]

Never…but i never thought about ramps having it easier but i guess i makes a little sense..Dies it need to be accessible? How are you getting out of a ramp in the first place…

 

[walker.t]

with three steps in the middle, connecting two levels with a small elevation difference.

Yes, your three risers are considered a stairway, therefore you must use the capacity factor in 1005.3.1 Stairways.

Definitions from 2021 IBC Chapter 2 (emphasis added):
Flight
A continuous run of rectangular treads, winders or combination thereof from one landing to another.

Stair
A change in elevation, consisting of one or more risers.

Stairway
One or more flights of stair, either exterior or interior, with the necessary landings and platforms connecting them, to form a continuous and uninterrupted passage from one level to another.

ICC commentary on 2021 IBC Chapter 2 definition of “Stair”
All steps, even a single step, are defined as a stair. This makes the stair requirements applicable to all steps unless specifically exempt in the code.

If yes, I should replace the steps with a ramp.

Remember to confirm you have the floor space for the 60” landings at the top and bottom of the ramp.

 

[Yankee Chronicler]

I'm not sure if "three steps" means four treads and three risers, or three treads and two risers. Either way, in my opinion that's a flight of stairs.

IBC 2021 definitions:

[BE] FLIGHT. A continuous run of rectangular treads, winders
or combination thereof from one landing to another.

[BE] STAIR. A change in elevation, consisting of one or more
risers.

IBC Commentary on the definition of "Stair":

All steps, even a single step, are defined as a stair.
This makes the stair requirements applicable to all
steps unless specifically exempt in the code.