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Re: railings

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In a message dated 12/11/98 8:03:57 PM EST, jonj(--nospam--at)spectraustin.com writes:

<< On a related matter, has anyone else had difficulty convincing an architect
 that 1 1/4-inch diameter standard pipe guardrail posts do not accommodate
 the code required concentrated force of 200 pounds or a uniform load of 50
 pounds per foot at the top of the rail (at a height of 3'-6")?  
 
 Using ASD, we've determined that it's necessary to utilize 1 1/2-inch
 diameter extra-strong pipe at a maximum spacing of 4'-6" on center.  The
 architects don't like this because the outside diameter of 1 1/2-inch pipe
 is 1.90 inches.  They prefer to keep the O.D. to 1 1/2 inches (even though
 the O.D. of 1 1/4-inch pipe is 1.66"!).
 
 I continue to see drawings prepared by other architects or A/E's that
 overlook this requirement.  Although railing systems are generally
 addressed on the architectural drawings and/or specifications, we feel duty
 bound to bring this to their attention.
 
 Jon D. Jelinek, P.E.
 SPECTRA Consulting Engineers
 Austin, TX
 
 jonj(--nospam--at)spectraustin.com
  >>

You can reduce the 200 pound load if you have a two span railing or more.  The
theory is that as one stanchion deflects, the railing will distribute the load
to the next adjacent stanchion.  There are reduction factors (end posts: 85%,
intermediate posts : 65%)  which you can use.  See if you can get ahold of the
National Association of Architectural Metal Manufacturers (NAAMM) manual on
pipe railing. My manual is from 1977 and has the association located in Oak
Park, ILLinois.  The testing was done in the late 1970's I believe by Wiss,
Janey, Eliser (sp?).

As far as the size of the handrail being limited to 1-1/2" round, this was
suppose to be nominal which means you could use 1-1/4 (o.d. = 1.66) and 1-1/2
(o.d. = 1.90).  Julius Blum which is a major manufacturer of stair components
in New Jersey has a letter from the General Counsel for the Access Board
which provides technical assistance with respect to the American with
Disabilites Act Accessiblility Guidelines stating that 1-1/4 and 1-1/2 pipe
are acceptable for handrails.  But he also includes a disclamer  that the
Department of Justice is responsible for enforcement of certain titles of the
act and that his letter only provides informal guidance. That the letter is
not a determination of ones legal rights or responsibilities under the ADA and
is not binding on the Access Board or the Department of Justice.

I guess that translates into that only the Supreme Court can decide if 1-1/4
or 1-1/2 inch pipe is acceptable, which means someone would have to bring a
lawsuit over using too large of a pipe diameter for the handrail.  The
architects I have spoken with don't want to take a chance on being this
particular  test case.

Mike Cochran