The width of landings shall not be less than the width of stairways they serve. Every landing shall have a minimum dimension measured in the direction of travel equal to the width of the stairway. Such dimension need not exceed 48 inches (1219 mm) where the stairway has a straight run.
Bolding mine.Most jurisdictions that adopt and enforce a building code in the US
base it on the International Building Code, which is developed by the
International Code Council, who are in the majority building
officials. The IBC includes:
"105.2 Work exempt from permit. Exemptions from permit requirements of
this code shall not be deemed to grant authorization for any work to be
done in any manner in violation of the provisions of this code or any
other laws or ordinances of this jurisdiction. Permits shall not be
required for the following:
8. Temporary motion picture, television and theater stage sets and scenery."
The model code may be amended in the normal legislative process of the
jurisdiction so you would have to look at the actual legislation for
your jurisdiction to see if this exemption is deleted in the area
where you work.