TABLE OF CONTENTS The examples below are intended to illustrate concepts presented in Chapter 8.
In a wastepaper basket, a fire starts due to a discarded cigarette, which smolders for several minutes and eventually leads to ignition of the contents and wastebasket in a hospital waiting room. This fire radiates sufficient energy to ignite an adjacent couch constructed of wood and polyurethane foam. The fire grows enough to ignite an adjacent wooden wardrobe that provides sufficient heat to cause the room to flashover. Most nonstaff occupants are nonambulatory and are not familiar with the exits or evacuation procedures. The staff has been trained with regard to emergency procedures during a fire incident.
Consider the design of a smoke detection system and a failure analysis to identify ways in which the detection system might not perform as expected. Ambient conditions, such as thermal layering, local heat sources, or the air flow generated by the HVAC system, might prevent smoke from reaching the detector. Thermal layering (e.g., in a tall space such as an atrium) might be sufficient to prevent an automatic sprinkler head from operating with a fire at the first-floor level. Maintenance conditions might also affect the ability of a detection system to perform as expected.
Each of these possibilities might then be considered as parts of fire scenarios. If these fire scenarios were used as design fire scenarios, the impact of these possible failures might be considered. If the detection system were used as part of a...
