Adding Temporary Stairs, Front of Stage into Aisle

[Jason M Wagner]

Railing Need??

We have a company that has built a set of stairs leading up from our audience area onto the stage. Normally, the only way to the stage is to walk around to the sides and enter onto the far sides of the apron.

The height of the stage from the floor- 41.5"

Stairs the client has built-
4 steps, plus 1 to the stage (landing)
Height- 32.25"
Width- 36"
Rise- 8" (last step from stairs to stage 9.25")
Tread- 10"
Travel angle- 41.4 deg

The dancers will be choosing and assisting audience members up onto the stage.

The question is! Do I need a railing?

Thank you,

Wags

 

[Footer]

Audience on it? Yes, you need a railing.

 

[BillConnerFASTC]

The unequal rises and the in excess of 7" rise and less than 10" run make this not code compliant. Yes it needs a handrail. If I were in your position, I'd either not allow it or insist the group that built and installed it have insurance and admit they are liable in writing.

The "cost" to society from falls on stairs is greater than the cost of vehicular accidents, I think by a factor of 10. I remember watching the Tony Awards one year - long ago - and seeing Boris Aronson fall on similar steps to the stage to accept the award. He died in 1980 so quite a while ago, and before everything was on youtube apparently

 

[Jason M Wagner]

Thank you for your advice.

However I wonder about the "excess of 7" rise and less than 10" run" you mention. The table below seems to state the rise and run are acceptable for a stairway of 41-44 deg horizontal angle.

Am I misreading??

According to 1910.24(e) (https://www.osha.gov/pls/oshaweb/owadisp.show_document?p_table=STANDARDS&p_id=9716):

" 'Angle of stairway rise.' Fixed stairs shall be installed at angles to the horizontal of between 30 deg. and 50 deg. Any uniform combination of rise/tread dimensions may be used that will result in a stairway at an angle to the horizontal within the permissible range. Table D-1 gives rise/tread dimensions which will produce a stairway within the permissible range, stating the angle to the horizontal produced by each combination. However, the rise/tread combinations are not limited to those given in Table D-1.
Table D-1
____________________________________________________________________
| |
Angle to horizontal | Rise (in inches) | Tread run (in inches)
__________________________|__________________|______________________
| |
30 deg. 35'...............| 6 1/2 | 11
32 deg. 08'...............| 6 3/4 | 10 3/4
33 deg. 41'...............| 7 | 10 1/2
35 deg. 16'...............| 7 1/4 | 10 1/4
36 deg. 52'...............| 7 1/2 | 10
38 deg. 29'...............| 7 3/4 | 9 3/4
40 deg. 08'...............| 8 | 9 1/2
41 deg. 44'...............| 8 1/4 | 9 1/4
43 deg. 22'...............| 8 1/2 | 9
45 deg. 00'...............| 8 3/4 | 8 3/4
46 deg. 38'...............| 9 | 8 1/2
48 deg. 16'...............| 9 1/4 | 8 1/4
49 deg. 54'...............| 9 1/2 | 8
__________________________|__________________|______________________
"


Concerning the lack of a handrail and mis-sized last step, I agree.


Thanks again!

 

[lighthouse]

Residential building codes restrict the rise to 7 3/4" (as of 2009, anyways). I expect similar restrictions exist for publicly used stairways in a commercial building.

 

[BillConnerFASTC]

Both the International Building Code and the Life Safety Code limit stars to maximum 7" rise and minimum 11" run - and note run does not included adding for a nosing - just the clear projected plan space. There are exceptions, but not many and not for stairs to a stage in an assembly occupancy.

You left out the application of that OSHA section: "This section contains specifications for the safe design and construction of fixed general industrial stairs. This classification includes interior and exterior stairs around machinery, tanks, and other equipment, and stairs leading to or from floors, platforms, or pits. This section does not apply to stairs used for fire exit purposes, to construction operations to private residences, or to articulated stairs, such as may be installed on floating roof tanks or on dock facilities, the angle of which changes with the rise and fall of the base support."

These stairs are a part of the means of egress and are regulated by the building and fire codes, not OSHA.

And based on the research I've seen - imagine spending days at conferences on stair safety over many years and having one of the top 3 or 4 experts on stairs in the world as a friend http://www.bldguse.com/Welcome.html - a good stair would be more like 6 1/2" max rise and 13" min. run. 7/11 is code minimum - meaning you pass with a grade of D-.

 

[Jason M Wagner]

Thank you so much for the info. This is all very helpful. I appreciate you pointing out the "application" part.

 

[BillConnerFASTC]

And handrails on both sides.

From IBC:

1011.5 Stair treads and risers. Stair treads and risers shall
comply with Sections 1011.5.1 through 1011.5.5.3.
1011.5.1 Dimension reference surfaces. For the purpose
of this section, all dimensions are exclusive of carpets,
rugs or runners.
1011.5.2 Riser height and tread depth. Stair riser
heights shall be 7 inches (178 mm) maximum and 4 inches
(102 mm) minimum. The riser height shall be measured
vertically between the nosings of adjacent treads. Rectangular
tread depths shall be 11 inches (279 mm) minimum
measured horizontally between the vertical planes of the
foremost projection of adjacent treads and at a right angle
to the tread’s nosing. Winder treads shall have a minimum
tread depth of 11 inches (279 mm) between the vertical
planes of the foremost projection of adjacent treads at the
intersections with the walkline and a minimum tread depth
of 10 inches (254 mm) within the clear width of the stair.

AND

1011.5.4 Dimensional uniformity. Stair treads and risers
shall be of uniform size and shape. The tolerance between
the largest and smallest riser height or between the largest
and smallest tread depth shall not exceed 3/8 inch (9.5 mm)
in any flight of stairs. The greatest winder tread depth at
the walkline within any flight of stairs shall not exceed the
smallest by more than 3/8 inch (9.5 mm).

 

[JerseyMatt]

Honestly I think the 1 1/4" difference at the top step is a bigger trip/fall hazard than the non-conforming rise/run.

 

[BillConnerFASTC]

Honestly I think the 1 1/4" difference at the top step is a bigger trip/fall hazard than the non-conforming rise/run.

I agree, close to lack of handrail.

 

[BillConnerFASTC]

Pardon me but what's a "lavk"?
Toodleoo!
Ron Hebbard

A fat fingered smart phone "lack". Corrected.