Exit capacity - Revision history

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2026-11-02T17:14:33Z

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	Flow is therefore small at both low and very high densities and reaches a peak at an intermediate density of around 2 persons per m².<ref name="Proulx-3-346" /> Nelson and Mowrer use a linear relation between speed and density for densities between 0.54 and 3.8 persons per m². Below that range people walk at their own pace, and above it nobody moves until the crowd has thinned out.<ref name="NM-3-370">Nelson and Mowrer (2002), p. 3-370.</ref> In their method the flow per metre of width reaches its maximum at a density of 1.9 persons per m².<ref name="NM-3-371" /> The book ''Introduction to Fire Safety Engineering'' shows the same pattern with data from the London Transport Board of 1958. The capacity of an escape route rises up to a density of about 4.5 persons per m² and then drops sharply as congestion sets in.<ref name="VR-7.4" />		Flow is therefore small at both low and very high densities and reaches a peak at an intermediate density of around 2 persons per m².<ref name="Proulx-3-346" /> Nelson and Mowrer use a linear relation between speed and density for densities between 0.54 and 3.8 persons per m². Below that range people walk at their own pace, and above it nobody moves until the crowd has thinned out.<ref name="NM-3-370">Nelson and Mowrer (2002), p. 3-370.</ref> In their method the flow per metre of width reaches its maximum at a density of 1.9 persons per m².<ref name="NM-3-371" /> The book ''Introduction to Fire Safety Engineering'' shows the same pattern with data from the London Transport Board of 1958. The capacity of an escape route rises up to a density of about 4.5 persons per m² and then drops sharply as congestion sets in.<ref name="VR-7.4" />

			[[File:fse-exit-capacity-v1.svg\|thumb\|upright=1.5\|alt=Line chart: specific flow against crowd density, three arch-shaped curves peaking at 1.9 persons per square metre, highest for corridors and doors.\|Specific flow against crowd density for corridors and doorways and for a steep and a shallow stair. Based on Nelson and Mowrer (2002), pp. 3-370 to 3-371.]]

	Flow per unit of width is called [[specific flow]]. Nelson and Mowrer give maximum values of 1.3 persons per second per metre of effective width for corridors, aisles, ramps and doorways. For stairs the maximum ranges from 0.94 for steep stairs (190 mm risers, 254 mm treads) to 1.16 for shallow stairs (165 mm risers, 330 mm treads).<ref name="NM-3-371" /> Observations of total evacuations of office buildings gave an optimum on stairs of 1.18 persons per second per metre of effective width, at 2.0 persons per m² and 0.5 m/s along the stair.<ref name="Proulx-3-347" /> On a typical stair 1,120 mm wide this meant one person per second, each person occupying slightly less than two treads and descending one storey every 15 seconds.<ref name="Proulx-3-346" />		Flow per unit of width is called [[specific flow]]. Nelson and Mowrer give maximum values of 1.3 persons per second per metre of effective width for corridors, aisles, ramps and doorways. For stairs the maximum ranges from 0.94 for steep stairs (190 mm risers, 254 mm treads) to 1.16 for shallow stairs (165 mm risers, 330 mm treads).<ref name="NM-3-371" /> Observations of total evacuations of office buildings gave an optimum on stairs of 1.18 persons per second per metre of effective width, at 2.0 persons per m² and 0.5 m/s along the stair.<ref name="Proulx-3-347" /> On a typical stair 1,120 mm wide this meant one person per second, each person occupying slightly less than two treads and descending one storey every 15 seconds.<ref name="Proulx-3-346" />
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	== Effective width ==		== Effective width ==
	People walking through an exit route keep a small clearance from walls, handrails and other obstacles, to allow for body sway and to keep their balance. The useful or effective width is therefore the clear width minus a boundary layer on each side.<ref name="NM-3-368">Nelson and Mowrer (2002), p. 3-368.</ref> The boundary layers are 15 cm at stair walls and doors, 20 cm at corridor walls, 9 cm at handrails, 10 cm at obstacles and 46 cm in wide concourses. Next to theatre chairs and stadium benches the boundary layer is zero.<ref name="NM-3-369">Nelson and Mowrer (2002), p. 3-369.</ref>		People walking through an exit route keep a small clearance from walls, handrails and other obstacles, to allow for body sway and to keep their balance. The useful or effective width is therefore the clear width minus a boundary layer on each side.<ref name="NM-3-368">Nelson and Mowrer (2002), p. 3-368.</ref> The boundary layers are 15 cm at stair walls and doors, 20 cm at corridor walls, 9 cm at handrails, 10 cm at obstacles and 46 cm in wide concourses. Next to theatre chairs and stadium benches the boundary layer is zero.<ref name="NM-3-369">Nelson and Mowrer (2002), p. 3-369.</ref>

			[[File:fse-exit-capacity-v2.svg\|thumb\|upright=1.5\|alt=Three plan views of a door, a corridor and a stair, each with shaded strips along the edges and a narrower effective width in the middle.\|Effective width of a door, a corridor and a stair: the clear width minus a boundary layer on each side. Based on Nelson and Mowrer (2002), pp. 3-368 to 3-369.]]

	For stairs this means that the effective width is 300 mm less than the nominal width credited in building codes. A stair with a nominal width of 1,120 mm has an effective width of about 812 mm.<ref name="Proulx-3-347" /> The boundary layer concept explains why capacity is not simply proportional to the measured width. In New Zealand, C/VM2 (second edition, 2025) uses the same boundary layer values to calculate the effective width of doors, stairs and corridors.<ref name="MBIE-33">Ministry of Business, Innovation and Employment (2025b), p. 33.</ref>		For stairs this means that the effective width is 300 mm less than the nominal width credited in building codes. A stair with a nominal width of 1,120 mm has an effective width of about 812 mm.<ref name="Proulx-3-347" /> The boundary layer concept explains why capacity is not simply proportional to the measured width. In New Zealand, C/VM2 (second edition, 2025) uses the same boundary layer values to calculate the effective width of doors, stairs and corridors.<ref name="MBIE-33">Ministry of Business, Innovation and Employment (2025b), p. 33.</ref>
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	The book gives a worked example for 300 people leaving a space by four stairs: two of 2.4 m and two of 1.6 m wide. It uses the Dutch flow capacity of 45 persons per metre per minute for stairs, a walking speed of 1 m/s and an equal split of 75 people per stair.<ref name="VR-7.5" /> A stair 1.6 m wide then passes 1.6 × 45 = 72 persons per minute, or 1.2 persons per second, so the narrow stairs govern. The flow time is 75 / 1.2 = 63 s, rounded up. The first person needs 5 s to reach the stair and the last person 10 s from the stair to the exit, so the evacuation time is 5 + 63 + 10 = 78 s.<ref name="VR-7.5" />		The book gives a worked example for 300 people leaving a space by four stairs: two of 2.4 m and two of 1.6 m wide. It uses the Dutch flow capacity of 45 persons per metre per minute for stairs, a walking speed of 1 m/s and an equal split of 75 people per stair.<ref name="VR-7.5" /> A stair 1.6 m wide then passes 1.6 × 45 = 72 persons per minute, or 1.2 persons per second, so the narrow stairs govern. The flow time is 75 / 1.2 = 63 s, rounded up. The first person needs 5 s to reach the stair and the last person 10 s from the stair to the exit, so the evacuation time is 5 + 63 + 10 = 78 s.<ref name="VR-7.5" />

			[[File:fse-exit-capacity-v3.svg\|thumb\|upright=1.5\|alt=Plan of a hall with 300 people and four stairs, 75 people each; a timeline adds 5 s walking, 63 s flow time and 10 s walking to 78 s.\|Hand calculation of evacuation time for 300 people and four stairs: the 1.6 m stairs govern, giving 5 + 63 + 10 = 78 s. Based on Van Rossum (2027), §7.5.]]

	The same stair can be checked with the values of Nelson and Mowrer. With a boundary layer of 0.15 m on each side, the effective width is 1.3 m. With maximum specific flows of 0.94 to 1.16 persons per second per metre for stairs, the flow is 1.2 to 1.5 persons per second.<ref name="NM-3-369" /><ref name="NM-3-371" /> The flow time for 75 people then lies between 50 and 62 s, close to the book's result. Both methods assume ideal conditions. Nelson and Mowrer stress that real evacuations are usually slower than the modelled time, for example because some exits are overloaded while others are hardly used.<ref name="NM-3-368" />		The same stair can be checked with the values of Nelson and Mowrer. With a boundary layer of 0.15 m on each side, the effective width is 1.3 m. With maximum specific flows of 0.94 to 1.16 persons per second per metre for stairs, the flow is 1.2 to 1.5 persons per second.<ref name="NM-3-369" /><ref name="NM-3-371" /> The flow time for 75 people then lies between 50 and 62 s, close to the book's result. Both methods assume ideal conditions. Nelson and Mowrer stress that real evacuations are usually slower than the modelled time, for example because some exits are overloaded while others are hardly used.<ref name="NM-3-368" />
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	In New Zealand, C/VM2 calculates the flow through a door with the same equation as Nelson and Mowrer, with a density of 1.9 persons per m². For a standard door leaf with a self-closer, the flow is capped at 50 persons per minute. This corresponds to a door 0.95 m wide with an effective width of 0.65 m.<ref name="MBIE-33" /><ref name="MBIE-34">Ministry of Business, Innovation and Employment (2025b), p. 34.</ref> The cap reflects the way a self-closing door leaf gets in the way of the people passing through it. If the door is held open or has no self-closer, the full flow from the equation applies, and an automatic sliding door counts with its full effective width once it is open.<ref name="MBIE-34" /> A double door with self-closers on both leaves can pass at most 100 persons per minute.<ref name="MBIE-34" />		In New Zealand, C/VM2 calculates the flow through a door with the same equation as Nelson and Mowrer, with a density of 1.9 persons per m². For a standard door leaf with a self-closer, the flow is capped at 50 persons per minute. This corresponds to a door 0.95 m wide with an effective width of 0.65 m.<ref name="MBIE-33" /><ref name="MBIE-34">Ministry of Business, Innovation and Employment (2025b), p. 34.</ref> The cap reflects the way a self-closing door leaf gets in the way of the people passing through it. If the door is held open or has no self-closer, the full flow from the equation applies, and an automatic sliding door counts with its full effective width once it is open.<ref name="MBIE-34" /> A double door with self-closers on both leaves can pass at most 100 persons per minute.<ref name="MBIE-34" />

			[[File:fse-exit-capacity-v4.svg\|thumb\|upright=1.5\|alt=Line chart: door flow rising linearly with effective width, about 79 persons per minute per metre, with a horizontal cap at 50 persons per minute.\|Flow through a doorway against effective width in C/VM2, with the cap of 50 persons per minute for a self-closing door leaf. Based on Ministry of Business, Innovation and Employment (2025b), pp. 33–34.]]

	C/VM2 also limits how people may be assumed to spread over the exits. A main entrance must be designed for half of the occupants, and without a main entrance no exit may be given more than half of the occupants.<ref name="MBIE-32" /> Doors on escape routes used by more than 50 occupants must open in the direction of escape.<ref name="MBIE-32" />		C/VM2 also limits how people may be assumed to spread over the exits. A main entrance must be designed for half of the occupants, and without a main entrance no exit may be given more than half of the occupants.<ref name="MBIE-32" /> Doors on escape routes used by more than 50 occupants must open in the direction of escape.<ref name="MBIE-32" />

Daan: New FSE wiki article: Exit capacity (written by Claude Opus 5.5)

2026-11-01T22:48:37Z

New FSE wiki article: Exit capacity (written by Claude Opus 5.5)

New page

'''Exit capacity''' is the number of people that an exit, stair, door or corridor can pass in a given time, or the number of people for whom it is designed. It is usually expressed per metre of width, for example as persons per metre per minute or persons per second per metre of effective width.<ref name="NM-3-371">Nelson and Mowrer (2002), p. 3-371.</ref><ref name="VR-7.4">Van Rossum (2027), §7.4.</ref> Together with walking speed, exit capacity determines the evacuation time of a building. When many people reach an exit at once, the time they need to pass it, the flow time, usually decides how long the evacuation takes.<ref name="Proulx-3-347">Proulx (2002), p. 3-347.</ref>

Measured flows reach about one person per second through a typical office stair 1,120 mm wide, and up to about 1.3 persons per second per metre of effective width through doors and corridors.<ref name="Proulx-3-346">Proulx (2002), p. 3-346.</ref><ref name="NM-3-371" /> Building regulations translate this into simple rules. Examples are a fixed number of persons per metre of door or stair width in the Netherlands, or units of exit width in the United States.<ref name="VR-7.4" /><ref name="Averill-18">Averill et al. (2005), p. 18.</ref> Performance-based design calculates flow times directly and adds them to the other parts of the required safe egress time.<ref name="MBIE-32">Ministry of Business, Innovation and Employment (2025b), p. 32.</ref>

== Flow, speed and crowd density ==
The movement of a crowd through an exit is described by three quantities: speed, density and flow. Proulx gives the basic relation: the flow equals the speed times the density times the width of the walkway, with the speed measured along the slope for stairs.<ref name="Proulx-3-346" /> Speed depends on density. When there is less than about 0.5 person per m², people walk at about 1.25 m/s, their normal unrestricted speed. At higher densities they slow down, and at 4 or 5 persons per m², comparable to a crowded lift, movement stops.<ref name="Proulx-3-346" />

Flow is therefore small at both low and very high densities and reaches a peak at an intermediate density of around 2 persons per m².<ref name="Proulx-3-346" /> Nelson and Mowrer use a linear relation between speed and density for densities between 0.54 and 3.8 persons per m². Below that range people walk at their own pace, and above it nobody moves until the crowd has thinned out.<ref name="NM-3-370">Nelson and Mowrer (2002), p. 3-370.</ref> In their method the flow per metre of width reaches its maximum at a density of 1.9 persons per m².<ref name="NM-3-371" /> The book ''Introduction to Fire Safety Engineering'' shows the same pattern with data from the London Transport Board of 1958. The capacity of an escape route rises up to a density of about 4.5 persons per m² and then drops sharply as congestion sets in.<ref name="VR-7.4" />

Flow per unit of width is called [[specific flow]]. Nelson and Mowrer give maximum values of 1.3 persons per second per metre of effective width for corridors, aisles, ramps and doorways. For stairs the maximum ranges from 0.94 for steep stairs (190 mm risers, 254 mm treads) to 1.16 for shallow stairs (165 mm risers, 330 mm treads).<ref name="NM-3-371" /> Observations of total evacuations of office buildings gave an optimum on stairs of 1.18 persons per second per metre of effective width, at 2.0 persons per m² and 0.5 m/s along the stair.<ref name="Proulx-3-347" /> On a typical stair 1,120 mm wide this meant one person per second, each person occupying slightly less than two treads and descending one storey every 15 seconds.<ref name="Proulx-3-346" />

For design, Proulx refers to the levels of service of Fruin, which range from A, with little chance of congestion, to F, with much congestion. For emergency movement in limited space, levels C, D and E are recommended. These correspond to flows of about 0.5 to 1.4 persons per second per metre of effective width on level walkways and 0.4 to 0.9 on stairs.<ref name="Proulx-3-347" /> Ramps with slopes up to about 5 % do not reduce walking speed. An upward slope of 10 % reduces it by about 10 %, and an unusually steep upward slope of 20 % by about 25 %.<ref name="Proulx-3-347" />

== Effective width ==
People walking through an exit route keep a small clearance from walls, handrails and other obstacles, to allow for body sway and to keep their balance. The useful or effective width is therefore the clear width minus a boundary layer on each side.<ref name="NM-3-368">Nelson and Mowrer (2002), p. 3-368.</ref> The boundary layers are 15 cm at stair walls and doors, 20 cm at corridor walls, 9 cm at handrails, 10 cm at obstacles and 46 cm in wide concourses. Next to theatre chairs and stadium benches the boundary layer is zero.<ref name="NM-3-369">Nelson and Mowrer (2002), p. 3-369.</ref>

For stairs this means that the effective width is 300 mm less than the nominal width credited in building codes. A stair with a nominal width of 1,120 mm has an effective width of about 812 mm.<ref name="Proulx-3-347" /> The boundary layer concept explains why capacity is not simply proportional to the measured width. In New Zealand, C/VM2 (second edition, 2025) uses the same boundary layer values to calculate the effective width of doors, stairs and corridors.<ref name="MBIE-33">Ministry of Business, Innovation and Employment (2025b), p. 33.</ref>

== Calculating flow time ==
The time needed for a group of people to pass a point in an exit route follows directly from the flow rate. Nelson and Mowrer write it as the number of people divided by the calculated flow, which is the specific flow times the effective width.<ref name="NM-3-371" /> The book uses the same relation in step 6 of its hand calculation, with the flow capacity per metre of width, the width and the number of people.<ref name="VR-7.5">Van Rossum (2027), §7.5.</ref>

<math display="block">t_\text{flow} = \frac{P}{F_s \, W_e}</math>

{| class="wikitable"
! Symbol !! Description !! Unit
|-
| <math>t_\text{flow}</math> || flow time: time for the whole group to pass the exit || s
|-
| <math>P</math> || number of people assigned to the exit || persons
|-
| <math>F_s</math> || specific flow, the flow per metre of effective width || persons/(s·m)
|-
| <math>W_e</math> || effective width of the exit (clear width minus boundary layers) || m
|}

The relation is the core of the [[hydraulic evacuation model]]. It assumes that all people start at the same moment, that the flow is not interrupted by individual decisions, and that nearly everyone can keep up with the group.<ref name="NM-3-367">Nelson and Mowrer (2002), p. 3-367.</ref> Where a route narrows or two flows merge, the outgoing flow cannot exceed the maximum specific flow times the effective width of the next element. If more people arrive, a queue forms.<ref name="NM-3-372">Nelson and Mowrer (2002), p. 3-372.</ref> In a time-based analysis, the evacuation time of a space is the larger of the walking time to the exit and the flow time through it.<ref name="MBIE-32" /> The flow time then becomes part of the [[required safe egress time]].<ref name="MBIE-32" />

The book gives a worked example for 300 people leaving a space by four stairs: two of 2.4 m and two of 1.6 m wide. It uses the Dutch flow capacity of 45 persons per metre per minute for stairs, a walking speed of 1 m/s and an equal split of 75 people per stair.<ref name="VR-7.5" /> A stair 1.6 m wide then passes 1.6 × 45 = 72 persons per minute, or 1.2 persons per second, so the narrow stairs govern. The flow time is 75 / 1.2 = 63 s, rounded up. The first person needs 5 s to reach the stair and the last person 10 s from the stair to the exit, so the evacuation time is 5 + 63 + 10 = 78 s.<ref name="VR-7.5" />

The same stair can be checked with the values of Nelson and Mowrer. With a boundary layer of 0.15 m on each side, the effective width is 1.3 m. With maximum specific flows of 0.94 to 1.16 persons per second per metre for stairs, the flow is 1.2 to 1.5 persons per second.<ref name="NM-3-369" /><ref name="NM-3-371" /> The flow time for 75 people then lies between 50 and 62 s, close to the book's result. Both methods assume ideal conditions. Nelson and Mowrer stress that real evacuations are usually slower than the modelled time, for example because some exits are overloaded while others are hardly used.<ref name="NM-3-368" />

== Exit capacity in regulations ==
In the Netherlands, building regulations have set requirements for the width of escape doors since 1992. After the limit for the flow capacity of escape doors was questioned, TU Delft carried out laboratory experiments in 2009. In 13 of the 16 experiments the average measured capacity of a doorway was higher than 135 persons per minute.<ref name="VR-7.4" /> Lower values were found with an open door, with a wide opening of 275 cm, and with a group that included people who could not move unaided. With 5 % of such people, the capacity was 10 % below 135 persons per minute, the lowest result.<ref name="VR-7.4" />

The results were included in the Dutch building decree (Bbl), which expresses flow capacity in persons per metre of clear width. The most common value is 90 persons per metre for a doorway. A stair has 45 persons per metre when it bridges a height of more than 1 m and 90 persons per metre for 1 m or less. Other passages, including sliding doors, have 135 persons per metre.<ref name="VR-7.4" /> The book lists these rules as the simplest way to determine evacuation time. More detailed options are a calculation of holding and flow capacity, a hand calculation and evacuation simulation.<ref name="VR-7.5" />

In New Zealand, C/VM2 calculates the flow through a door with the same equation as Nelson and Mowrer, with a density of 1.9 persons per m². For a standard door leaf with a self-closer, the flow is capped at 50 persons per minute. This corresponds to a door 0.95 m wide with an effective width of 0.65 m.<ref name="MBIE-33" /><ref name="MBIE-34">Ministry of Business, Innovation and Employment (2025b), p. 34.</ref> The cap reflects the way a self-closing door leaf gets in the way of the people passing through it. If the door is held open or has no self-closer, the full flow from the equation applies, and an automatic sliding door counts with its full effective width once it is open.<ref name="MBIE-34" /> A double door with self-closers on both leaves can pass at most 100 persons per minute.<ref name="MBIE-34" />

C/VM2 also limits how people may be assumed to spread over the exits. A main entrance must be designed for half of the occupants, and without a main entrance no exit may be given more than half of the occupants.<ref name="MBIE-32" /> Doors on escape routes used by more than 50 occupants must open in the direction of escape.<ref name="MBIE-32" />

In the United States, codes have long used units of exit width. The New York City code of 1938 allowed 30 persons per unit of exit width, and the code of 1968 allowed 60. That change effectively halved the required capacity of new buildings.<ref name="Averill-18" /> The International Building Code of 2003, as compared in the World Trade Center investigation, allows 0.005 m of exit width per person in fully sprinklered buildings. The New York code, the International Building Code and the Life Safety Code all allow the capacity of each stair to be doubled when two stairs are located in separated areas of refuge.<ref name="Averill-47">Averill et al. (2005), p. 47.</ref><ref name="Averill-48">Averill et al. (2005), p. 48.</ref> The required capacity is based on the [[occupant load]] of the area served, so capacity rules are always linked to occupant density assumptions.<ref name="Averill-47" />

Those assumptions can differ widely from reality. Studies in Canadian office buildings found that each occupant had on average about 25 m² of gross rentable area, whereas codes traditionally assume 9.3 m² per person. Code estimates of the number of occupants may therefore be wrong by a factor of more than two.<ref name="Proulx-3-355">Proulx (2002), p. 3-355.</ref>

== Experience from tall buildings ==
In tall buildings, exit capacity is a matter of time rather than of a single floor. NIST noted that the egress capacity required by building codes follows from calculations for a single floor, independent of the height of the building. It does not consider the time needed for a full building evacuation.<ref name="NIST-xxxix">National Institute of Standards and Technology (2005), p. xxxix.</ref> In the World Trade Center towers on 11 September 2001, the buildings were only a third to half occupied. The flow of people had slowed considerably some 20 minutes before each tower collapsed, which showed that the stair capacity was adequate that morning.<ref name="NIST-xxxviii">National Institute of Standards and Technology (2005), p. xxxviii.</ref><ref name="NIST-xxxix" />

NIST estimated that with 20,000 occupants per tower, evacuation by the stairs would have taken just over three hours. About 14,000 people might then have died, because the stairs could not have carried that many people in the available time.<ref name="NIST-xxxix" /> A fourth stair, which the New York code required because of the assembly spaces at the top of each tower, would probably have reduced this shortfall.<ref name="NIST-xxxix" /> During the bombing of 1993 the stairs met the code requirements for exit capacity, but they did not allow all occupants to leave quickly. Stair doors were held open by the crowd, which increased the airflow up the stairs caused by the stack effect.<ref name="FS-59">Ferreira and Strege (2005), p. 59.</ref>

== Limits of capacity calculations ==
Capacity values describe ideal flows. Nelson and Mowrer distinguish the modelled evacuation time from the actual time and introduce an apparent evacuation efficiency. It accounts for delays caused by wardens directing people, stopping and restarting at merging points, people delaying their own start, and unbalanced use of the exits.<ref name="NM-3-368" /> Drills confirm the last point. In 1972, a total evacuation of a 15-storey office building by four stairs took between 6.6 and 9.3 minutes per stair, mainly because the demand on the stairs was unequal.<ref name="Proulx-3-356">Proulx (2002), p. 3-356.</ref>

The way people are divided over the exits is uncertain. The book notes that both an equal split and a split in proportion to capacity are very optimistic assumptions.<ref name="VR-7.5" /> People prefer the route by which they entered the building and routes that look attractive, so some exits may be little used.<ref name="VR-7.3">Van Rossum (2027), §7.3.</ref> Capacity also falls when the group includes people who cannot walk unaided.<ref name="VR-7.4" /> C/VM2 therefore requires the egress analysis to cover the whole length of the [[means of escape|escape route]], so that the flow is not restricted at some point closer to the final exit.<ref name="MBIE-33" />

== See also ==
* [[Travel distance]]
* [[Walking speed]]
* [[Protected escape route]]
* [[Evacuation modelling]]

== Notes ==
<references />

== References ==
* Averill, J. D., Mileti, D. S., Peacock, R. D., Kuligowski, E. D., Groner, N., Proulx, G., Reneke, P. A., & Nelson, H. E. (2005). ''Occupant behavior, egress, and emergency communications'' (NIST NCSTAR 1-7). National Institute of Standards and Technology.
* Ferreira, M. J., & Strege, S. M. (2005). ''Smoke management systems'' (NIST NCSTAR 1-4D). National Institute of Standards and Technology.
* Ministry of Business, Innovation and Employment. (2025b). ''Verification Method C/VM2: Framework for fire safety design'' (2nd ed.).
* National Institute of Standards and Technology. (2005). ''Final report on the collapse of the World Trade Center towers'' (NIST NCSTAR 1).
* Nelson, H. E., & Mowrer, F. W. (2002). Emergency movement. In P. J. DiNenno, D. Drysdale, C. L. Beyler, W. D. Walton, R. L. P. Custer, J. R. Hall Jr., & J. M. Watts Jr. (Eds.), ''SFPE handbook of fire protection engineering'' (3rd ed., pp. 3-367–3-380). National Fire Protection Association; Society of Fire Protection Engineers.
* Proulx, G. (2002). Movement of people: The evacuation timing. In P. J. DiNenno, D. Drysdale, C. L. Beyler, W. D. Walton, R. L. P. Custer, J. R. Hall Jr., & J. M. Watts Jr. (Eds.), ''SFPE handbook of fire protection engineering'' (3rd ed., pp. 3-342–3-366). National Fire Protection Association; Society of Fire Protection Engineers.
* Van Rossum, E. (2027). ''Introduction to Fire Safety Engineering''. Fire Safety Academy.

[[Category:Human Behaviour & Evacuation]]