external access and evacuation technologies

[J N]

Any views:
The recent NIST Final Report Comment Submission dated September 13, 2005
Chapter 9.2 - NIST's Recommendations for "Improving the Safety on Buildings, Occupants, and Emegergency Responders"
9.26 Group 6 - Improved Emergency Response -
Pg 211, Recommendation 17, paragraph c, 1st sentence:
 
"If protected/hardened elevators are provided for emergency responders but become unsuable during emergency, due to a malfunction or a conventional treat whose magnitude exceeds the magnitude consider in design, sufficient means of evacuation and access capacity should be provided to ensure timely emergency responders access to buildings that are undergo full evacuation. Such capacity could be provided either via dedicated stairways for fire service use or by building sufficient stairway capacity (i.e., number and widths of stairways and/or use of scissor stairs credited as a single stair) or by external access and evacuation technologies to accomodate the evacuation of building occupants while allowing emergency access to emergency responders with minimal hindrance from occupant counterflow."
 
My questions and concern are:
 
Would Fire Chiefs allow their emergency responders to use the external access and evacuation technologies up the building if, protected/hardened elevators become unsuable during emergency?
 
Or would it be safer for emergency responders to climb up the stairways if its still passable?
 
Imagine in the worst case scenario, if both the protected/hardened elevators and the stairways are unpassable, and if the external access and evacuation technologies is still operational via power source, should Fire Chiefs allow their emergency responders to use such system to gain access to the building to fight fire or to perform search and rescue operations?
 
I would imagine under such extreme situations (probably the blaze gets out of control), the occupants entrapped above the fire floor(s) should attempt to use whatever external evacuation devices that are available to get out alive!
 
Many lessons were learned by FDNY from the WTC incidents, and would this NIST Recommendation 17 paragraph c, of Pg 211, formed the basis of revised  procedures for future high-rise rescue operations?
 
Any views or comments?

[Apollo_SG]

I am no fire-fighter... but my understanding is that the fire-fighters will be required to use staircases as a means of entering the fire floor, nevermind it is 50 storey up.

The basis for high rise fire-fighting is essentially based on internal fire-fighting not external.

To facilitate fire-fighters, the local regulations in Singapore requires all risers within each floors to be equipped with additional fire hoses, which is universal to the Service's equipment. So far, I have not come across incidents where such hoses are stolen.

Fireman access panels are generally used more for external fire-fighting when flaming may spread from lower floor to upper floor.

The 9/11 incident is abnormal and I don't suppose being risk adverse will really help in this context.  Most regulations eg NFPA 101 will require a minimum of 2 staircases which are usually spaced at more than 10m apart. And usually all floors are designed with re-entry so if one level is unpassable, you can proceed laterally to the other staircase.