unobstructed platform adjacent to stepped aisle

[sunyaer]

The following is from Ontario Building Code, Division B, Part 3
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3.3.2.4. Aisles
...
(26) If a step is used at the entry to a row of seats from a stepped aisle, an unobstructed platform not less than 800 mm
square shall be provided adjacent to the aisle.
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I can't imagine how the platform would look like in real situations where there is a stepped aisle. When there is a stepped aisle, the rows of seats would be on successive tiers, how would this situation accommodate a flat platform? (the 800mm platform would extend two to three treads of the stepped aisle, so the interface between the platform and aisle would look like this (cut a section along the stepped aisle), am I correct?

 

[bill1952]

I think the condition is rare, and most often is a step down into a row of seats from an aisle tread. The 800 mm square could be the space in a row in front of seats.

The only time I've done this is where a landing is required in a stepped aisle to change direction. Enter a balcony from side and landing for a 90 degree turn is in line with first row, but needs to be 1 step to second row, first row is a step or 2 down. (A better design is to let the landing project forward of the first row, which is not hard in a site built theatre, but you get into problems with factory grandstand and bleacher systems where "irregularities" are expensive.)

 

[Inspector Gadget]

You're thinking of a standard step = think of an arena or theatre where the steps are, like, 90 cm apart.

 

[bill1952]

You're thinking of a standard step = think of an arena or theatre where the steps are, like, 90 cm apart.

The op May be but I'm not. I'm very specifically addressing upper seating levels, stadia and arenas and performing arts balconies, where three 12" or 13" steps per 33" or 36" row is common, and having to have a landing to turn the aisle. You can't interrupt the seating pitch for sightlines, so that landing forces you to step down to rows in line with and below it.