...............I have seen problems with code officials on this as they may see the pipe as a
safety railing for the
catwalk with the associated maximum
spacing requirements, which typically precludes that large of an open space between rails.
This is an old and ongoing issue between
AHJ's/architects and
Theatre consultants/users/technicians. I once had an architect insist that he had to put a 4" square steel mesh between the pipe hanging
rail and the
rail below it because the gap between them was too big for code. I politely pointed out that it would be a tad difficult to hang a lighting
instrument there with the
wire mesh. They didn't listen and they paid to have the mesh added. Then the owner tried to use the space and they paid weekend double over time to have a crew come in and take it back out in time for the grand opening of the space.
There is an International Building Code exception to railings.See exception 5.
I posted off of the exceptions since so many deal with theatres, arenas,
etc. It also points out the uniqueness of our spaces. Where else but a
stage can you
hoist loads over people's heads? Lighting catwalks and loading bridges seem like the very definition of "special purpose runways". To paraphrase, there are no business buildings like show business buildings.
"1013.1 Where required. Guards shall be located along
open-sided walking surfaces, mezzanines, industrial equipment
platforms, stairways, ramps and landings that are located
more than 30 inches (762 mm) above the floor or grade below.
Guards shall be adequate in strength and attachment in accordance
with Section 1607.7. Where glass is used to provide a
guard or as a portion of the guard
system, the guard shall also
comply with Section 2407. Guards shall also be located along
glazed sides of stairways, ramps and landings that are located
more than 30 inches (762 mm) above the floor or grade below
where the glazing provided does not meet the strength and
attachment requirements in Section 1607.7.
Exception: Guards are not required for the following locations:
1. On the loading side of loading docks or piers.
2. On the audience side of stages and raised platforms,
including steps leading up to the
stage and raised platforms.
3. On raised
stage and
platform floor areas, such as runways,
ramps and side stages used for entertainment or
presentations.
4. At vertical openings in the performance area of stages
and platforms.
5. At elevated walking surfaces appurtenant to stages
and platforms for access to and utilization of special
lighting or equipment.
6. Along
vehicle service pits not accessible to the public.
7. In assembly seating where guards in accordance with
Section 1025.14 are permitted and provided."
The
NFPA Life
Safety Code is similar:
12.2.11.1.6 Locations Not Requiring Guards.
Guards shall not
be required in the following locations:
(1) Guards shall not be required on the audience side of
stages, of raised platforms, and of other raised floor areas
such as runways, ramps, and side stages used for entertainment
or presentations.
(2) Permanent guards shall not be required at vertical openings
in the performance area of stages.
(3) Guards shall not be required where the side of an elevated walking surface is required to be open for the normal
functioning of special lighting or for access and use of
other special equipment.
I'm sure most of us who regularly inspect theatres see that most lighting catwalks do not have
OSHA compliant guards. The number of catwalks that have provisions like a
track or zip
line is growing, though the use of it not so much. Most modern lighting (a.k.a Source 4's) of 19 degree or more, seem to function fine in a 22"
clear space between rails, so often that does not cause concern versus the building and fire codes 21" and
OSHA's 19" sphere rule. If we leave adequate space for 10 and 5 degree units or movers, then it is a different story.
Bottom
line, the codes do allow for lighting bridges and catwalks to be built in a usable manner, but you have to be vigilant during the planing and constriction
stage and present the correct information at the right time to the right people.