Design 
  Community 
  Architecture 
  Discussion 
 

Message - WTC locked stairwells - "Crossover Landings"?

    Responses | Architecture Forum | Architecture Students | Architecture Scrapbook | ArchitectureWeek    
   

Posted by  Mike Barkley on November 20, 2001 at 16:53:55:

I've been collecting accounts of locked stairwells and other
evacuation barriers from the WTC outrage at my website,
http://www.mjbarkl.com/locked.htm , and ran across the following
from the 1993 Bombing:

http://www.usfa.fema.gov/pdf/usfapubs/tr-076.pdf
"TR-076,The World Trade Center Bombing:
Report and Analysis"

[PDF p 151] "...2. Confusion on the stairs.
"Lack of familiarity with the stairs caused a number of problems.
One person noted that she stumbled at the stair landings in the
darkness, in part because the handrails did not continue the full
length of the stair flight. Other complaints involved not being
aware of the following: the existence of interior convenience
stairs; no reentry from the stairway for
security reasons (the locked doors frightened many people); and
"crossover" or extended landings, which, given the poor-visibility
conditions, made people fear they might be trapped (some crossovers
extended 50 feet and required going through a door).

"One person reportedly counted out loud the number of steps as
people were using them to evacuate. This let visually impaired
people know what to expect and was said to have a calming effect
on them. This is also how it was discovered that the flights of
stairs had inconsistent numbers of steps, adding to the confusion
of some with disabilities. (We later went into one of the stair
towers to see what was being described. At our point of entry,
there was a flight with 11 steps followed by flights with
Page 145
[PDF p 152]
six, eight, seven, nine, and five steps; followed by a crossover
measuring approximately 20 feet separated from the next flight by
a door; followed by flights of six steps, 13 steps, and so on.)..."

Does anybody know what these "crossover landings" were for?

--Mike Barkley, 161 N. Sheridan Ave. #1, Manteca, CA 95336
(H) 209/823-4817 - mjbarkl@inreach.com - MS is not Microsoft.

 
 
Search      ArchWeek      Buildings      Architects      Types      Places      Pix      Free 3D Models      Store      Library

Search GreatBuildings.com by name of Building, Architect, or Place:   
Examples:  "Fallingwater",  "Wright",  "Paris"           Advanced Search

Responses:




Post a Response -

Name:
E-Mail:

Subject:


 
Home | Great Buildings | CAD Outpost | DesignWorkshop | Free 3D | Gallery | Support | Search | ArchitectureWeek
This document is provided for on-line viewing only. /discussion/9096.html