When assessing the adequacy of the means of escape you will need to take into account:
• the findings of your fire risk assessment;
• the size of the workplace, its construction, layout, contents and the number and width of the available escape routes;
• the workplace activity, where people may be situated in the workplace and what they may be doing when a fire occurs;
• the number of people who may be present, and their familiarity with the workplace; and their ability to escape without assistance.”
7.0 What is a Means of Escape? The phrase 'means of escape' is seemingly self-explanatory; however, the variables involved with properties and structures in achieving the ‘best means of escape’ result in no singular answer. Some of the variables to be considered appear as you work through other sections of this element.
Given the exact nature of some of the information, in particular date and calculations, the information is directly extracted from regulation and legislation sources or guidelines for such documents.
Means of Escape is a structural means, whereby a safe route is provided for persons to escape in case of fire, from any point in a building to a place of safety, clear of the building, without outside assistance.
7.2 The principles of means of escape and general requirements Legislation requires that all buildings must be provided with adequate means of escape, so that, in the event of the fire, occupants of the building can escape to a place of safety beyond the building. To achieve this, the structural measures that constitute the means of escape (escape routes, staircases, and fire exits) must be supported by other measures, such as emergency escape lighting, fire warning systems, and fire safety signs
Wherever practicable, people should be able to turn their back on any fire and walk away towards a place of safety. Ideally, therefore, from any location, there should be at least two directions of escape leading to different exits that are unlikely to be affected by the same fire. Where this is not possible (e.g. small rooms with one exit, buildings with a single staircase and corridors that form 'dead ends'), it is necessary to impose certain additional restrictions.
It is necessary to consider the following when planning the means of escape:
• The maximum distance between any point and the nearest exit.
• The number of people for whom exits must be provided.
• The capacity of exits and staircases.
Travel distance is the maximum distance that people need to walk between any point in a story of the building and the nearest exit from the story. All design codes limit travel distance. In offices, where there are two alternative escape routes, the maximum travel distance is typically 45m. However, this is reduced to 18m if there is only one direction of escape.
The number of exits from any story and their width affects the total time taken to evacuate the story. Similarly, the number and width of staircases will affect the speed with which people on upper floors reach the ground floor level. Design codes, such as BS 5588-11, provide guidance on the number and width of exits and staircases, based on the number of people who will occupy the building.
For people on the upper stories of a building, there will be three stages of escape, involving:
• travel within rooms;
• horizontal travel to an exit from the story;
• vertical travel down staircases.
7.3 Alternative escape routes There is always the possibility of the path of a single escape route being rendered impassable by fire, smoke or fumes.
In certain conditions, a single direction of escape (a dead end) can be accepted as providing
associated fire risk, the size and height of the building, the extent of the dead end, and the numbers of persons accommodated within the dead end.
The basic principles for the design of means of escape are:
a. that there should be alternative means of escape from most situations;
b. where direct escape to a place of safety is not possible, it should be possible to reach a place of relative safety, such as a protected stairway, which is on a route to an exit, within a reasonable travel distance.
In such cases, the means of escape will consist of two parts, the first being unprotected in accommodation and circulation areas, and the second in protected stairways (and in some circumstances protected corridors).
In the event of a fire in a building, it is the smoke or fumes from the fire that can pose the greater threat. In particular, during the evacuation, people will have moved or been moving away from the place of the actual fire. We have just mentioned the provision of protected areas; a fundamental aspect of such areas is ventilation.
“The ultimate place of safety is the open air, clear of the effects of the fire. However, in modern buildings which are large and complex, reasonable safety may be reached within the building, provided suitable planning and protection measures are incorporated.”
7.4 Stairwell Ventilation Ventilators may be installed within a stairwell to create a safe exit route for occupants and a safe means of entry for fire-fighters.
In most residential applications, corridor ventilation, lobby ventilation, and stairwell ventilation work together to provide maximum smoke protection.
Vents showed in red.
• the findings of your fire risk assessment;
• the size of the workplace, its construction, layout, contents and the number and width of the available escape routes;
• the workplace activity, where people may be situated in the workplace and what they may be doing when a fire occurs;
• the number of people who may be present, and their familiarity with the workplace; and their ability to escape without assistance.”
7.0 What is a Means of Escape? The phrase 'means of escape' is seemingly self-explanatory; however, the variables involved with properties and structures in achieving the ‘best means of escape’ result in no singular answer. Some of the variables to be considered appear as you work through other sections of this element.
Given the exact nature of some of the information, in particular date and calculations, the information is directly extracted from regulation and legislation sources or guidelines for such documents.
Means of Escape is a structural means, whereby a safe route is provided for persons to escape in case of fire, from any point in a building to a place of safety, clear of the building, without outside assistance.
7.2 The principles of means of escape and general requirements Legislation requires that all buildings must be provided with adequate means of escape, so that, in the event of the fire, occupants of the building can escape to a place of safety beyond the building. To achieve this, the structural measures that constitute the means of escape (escape routes, staircases, and fire exits) must be supported by other measures, such as emergency escape lighting, fire warning systems, and fire safety signs
Wherever practicable, people should be able to turn their back on any fire and walk away towards a place of safety. Ideally, therefore, from any location, there should be at least two directions of escape leading to different exits that are unlikely to be affected by the same fire. Where this is not possible (e.g. small rooms with one exit, buildings with a single staircase and corridors that form 'dead ends'), it is necessary to impose certain additional restrictions.
It is necessary to consider the following when planning the means of escape:
• The maximum distance between any point and the nearest exit.
• The number of people for whom exits must be provided.
• The capacity of exits and staircases.
Travel distance is the maximum distance that people need to walk between any point in a story of the building and the nearest exit from the story. All design codes limit travel distance. In offices, where there are two alternative escape routes, the maximum travel distance is typically 45m. However, this is reduced to 18m if there is only one direction of escape.
The number of exits from any story and their width affects the total time taken to evacuate the story. Similarly, the number and width of staircases will affect the speed with which people on upper floors reach the ground floor level. Design codes, such as BS 5588-11, provide guidance on the number and width of exits and staircases, based on the number of people who will occupy the building.
For people on the upper stories of a building, there will be three stages of escape, involving:
• travel within rooms;
• horizontal travel to an exit from the story;
• vertical travel down staircases.
7.3 Alternative escape routes There is always the possibility of the path of a single escape route being rendered impassable by fire, smoke or fumes.
In certain conditions, a single direction of escape (a dead end) can be accepted as providing
associated fire risk, the size and height of the building, the extent of the dead end, and the numbers of persons accommodated within the dead end.
The basic principles for the design of means of escape are:
a. that there should be alternative means of escape from most situations;
b. where direct escape to a place of safety is not possible, it should be possible to reach a place of relative safety, such as a protected stairway, which is on a route to an exit, within a reasonable travel distance.
In such cases, the means of escape will consist of two parts, the first being unprotected in accommodation and circulation areas, and the second in protected stairways (and in some circumstances protected corridors).
In the event of a fire in a building, it is the smoke or fumes from the fire that can pose the greater threat. In particular, during the evacuation, people will have moved or been moving away from the place of the actual fire. We have just mentioned the provision of protected areas; a fundamental aspect of such areas is ventilation.
“The ultimate place of safety is the open air, clear of the effects of the fire. However, in modern buildings which are large and complex, reasonable safety may be reached within the building, provided suitable planning and protection measures are incorporated.”
7.4 Stairwell Ventilation Ventilators may be installed within a stairwell to create a safe exit route for occupants and a safe means of entry for fire-fighters.
In most residential applications, corridor ventilation, lobby ventilation, and stairwell ventilation work together to provide maximum smoke protection.
Vents showed in red.
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