Saturday, December 17, 2011

Railing on and on

My friends at Simplified Safety posted an interesting blog entry at http://simplifiedsafety.com/blog/safety-on-the-set-theatrical-guardrail/.  It shows the use of Kee Klamps and schedule 40 pipe to build a guardrail on a theatre set.  It is a well-intentioned application, however, it also clearly shows that the set designer / constructor did not fully understand the building codes and OSHA requirements for railings.
Railing along upstage platform.
Railings are intended to prevent people and objects from falling over an elevated edge.  To be successful they must not only stop someone from falling over the edge should their center of gravity extend past the edge, but they must also prevent someone from slipping under the railing AND they must prevent objects from being knocked / kicked off of the edge.

Translation:
  • The Upper Railing must be at least 42" above the platform (per International Building Code and OSHA). The railing in the picture scales to about 36" tall.
  • There must be a Toe-board (Kick-plate) that is 4" tall and the bottom of the Kick-plate must be no higher than 1/4'" above the platform.  There is no kick-plate present.
  • There must be intermediate railings or infill such that an sphere that is 21" diameter cannot pass through it (this limitation drops to a 4" if the railing is in a public place).  If the top of the top rail is at 42" and is 1.9" diameter, and the kick plate is 4" tall, then this leaves 36.1" of open space.  Installing an intermediate railing midway between the top of the kick plate and the bottom of the upper railing will satisfy this requirement.  There is no intermediate railing present.
  • Uprights for Railings must be in place ant no more than 8' intervals.  Just because you have a 20 foot piece of pipe doesn't mean that you can just install upright supports at the ends. The uprights in this application  appear to meet this requirement.
An additional requirement is that railing must support a load of at least 200 pounds pulling any direction.
  • Upwards:  Will it pull the railing right up out of the fittings or tear the bolts / pins / screws out?
  • Downwards:  Will it buckle and collapse under severe loading?
  • Sideways:  Will it collapse in a parallelogram?
  • Inwards or Outwards:  Will it support the weight of performers pulling or pushing on it, or falling against it, or leaning over it?
Kee Klamps can be a great tool to build frameworks, railings, platform supports, lighting towers, and many other elements in a theatre production.  As with any tool or fabrication, you must take the time to understand the building codes and do a structural analysis so that your finished product is strong enough to perform safely.

The Building Codes and OSHA do not differentiate between five seconds, five minutes, five days, or five years.  The objects you build, be they stairs, railings, platforms, or whatever must meet the requirements set forth -- regardless of how long they will be in service.

Well, at least it wasn't like this 8' unguarded drop behind the performer . . .

2 comments:

  1. Uncle Derek's reference is to the International Building Code (IBC), Chapter 1, Section 105.2 - "Work exempt from permit." The Code says: "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."

    For clarification: This only says that the need to get a construction permit is exempted - not the need to obey the Building Code. Check with your local building code Authority Having Jurisdiction (AHJ) to see what building code your venue operates under.

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