THE DOCUMENTATION PROVIDED ON AND THROUGH THIS PAGE IS FOR INFORMATION PURPOSES ONLY AND SHOULD NOT BE CONSTRUED AS LEGAL ADVICE.   IT IS SOLELY THE WORK OF ITS AUTHOR, WARREN F. DAVIS, AND HAS NOT BEEN APPROVED, ADOPTED OR SANCTIONED BY ANY OTHER ENTITY INCLUDING, BUT NOT LIMITED TO, ANY PEDESTRIAN DOOR MANUFACTURER, THE AMERICAN ASSOCIATION OF AUTOMATIC DOOR MANUFACTURERS (AAADM), THE BUILDERS HARDWARE MANUFACTURERS ASSOCIATION (BHMA), AND/OR THE AMERICAN NATIONAL STANDARDS INSTITUTE (ANSI).   THE AUTHOR AND DAVIS ASSOCIATES, INC., ASSUME NO RESPONSIBILITY WHATSOEVER FOR CONSEQUENCES OF ANY KIND OR NATURE THAT MAY ARISE FROM USE OF THE MATERIALS AND INFORMATION CONTAINED HEREIN.   THE USER ACCEPTS FULL AND COMPLETE RESPONSIBILITY FOR EVALUATING THE RELEVANCE AND APPLICABILITY OF THE INFORMATION CONTAINED HEREIN, AS WELL AS ITS ACCURACY AND VALIDITY AND, BY VIEWING OR DOWNLOADING ANY OF THE INFORMATION OR DOCUMENTATION CONTAINED HEREIN AGREES TO BE BOUND BY THESE TERMS, PROVISIONS AND CONDITIONS. |
The American National Standard for Power and Manual Operated Revolving Pedestrian Doors, ANSI/BHMA A156.27-2003, published and
copyrighted by the Builders Hardware Manufacturers Association, Inc., (BHMA) and approved by the American National Standards Institute,
Inc., (ANSI) on June 5, 2003, sets minimum standards applicable within the U.S. for the operation of manual and
automatic revolving pedestrian doors.   In particular, the Standard mandates limits based on user safety on the maximum rotational
kinetic energy that can be carried by such doors, and requires, in most cases, that if the kinetic energy of the door exceeds 2.5 lb-ft
(pound-feet) it must be equipped with so-called wing sensors either to stop the door, or at least to decrease its energy to less than
2.5 lb-ft to prevent injury to users as a consequence of being struck by the door.
ANSI A156.27-2003 contains an Appendix in which equations and a table are provided intended to enable users of the Standard to determine when, and if, the kinetic energy of a door meets or exceeds the 2.5 lb-ft limit.   Unfortunately, the equations and the table derived therefrom are incorrect and can result in significant underestimation of the kinetic energy carried by a door.   One possible consequence is failure to include mandated wing sensors on the door, with the result that a door user could be struck and seriously injured, or even killed. This web page links to an article describing the nature of the kinetic energy errors incorporated in ANSI A156.27-2003, and also presents the correct equations and energy table.   Yet further, the article presents the kinetic energy equation applicable to large 2-wing revolving doors that are equipped with "showcases", which are not covered by ANSI A156.27-2003 though such doors are equally subject to the kinetic energy limits imposed by the Standard. For those interested in the detailed mathematical derivation of the correct equations that should appear in the Appendix of the ANSI A156.27-2003 standard, click here. For those interested in the detailed mathematical derivation of the kinetic energy equations applicable to large 2-wing revolving doors equipped with a showcase at the outer end of each wing, click here.   Also available are derivations of the kinetic energy equations pertaining to 3-wing and 4-wing revolving doors with a polygonal core, and revolving doors with an arbitrary number of wings attached to a cylindrical core. |
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