Article 2: Establishing Exit Requirements [C26-601] SS.1 27-357 Exit conditions The occupancy group classification of the building, the number of people, the floor area, the travel distance to an exit, and the capacity of the exits, as specified in table 6-1 and herein, should be used to determine the exit requirements for a building. If these criteria are not met, then other factors such as location, design, construction, and maintenance must be considered.
Example 1: A two-story, 20,000 square foot office building has one exit on each floor. There is no stairway access between floors. Determine the required number of exits for this building.
The required number of exits is one per 2000 square feet of floor space. Since the total floor area of the building is 20,000 square feet, it meets the requirement for one exit per 2000 square feet of floor space.
Example 2: An eight-story, 200,000 square foot office building has one exit on each floor except for the top three floors which have two exits.
Since there are only four floors with single exits, they meet the requirement for one exit per 2000 square feet of floor space. However, since the top three floors have less than two exits per floor area, they do not meet the requirement for six exits per 1000 square feet of floor space.
In general, the number of needed exits is calculated by the building official depending on the kind of use and occupant load of the structure or area. 10 of the California Building Code or by contacting the Community Planning and Building Department. The number of exits should be adequate for the type of business carried on at any given time.
The required number of exits are divided into two categories: access and service. Access exits are those that provide egress from the premises for all employees and customers. These must be provided for each floor served by a single elevator. Service exits are those that provide egress for specific groups within the building. For example, a hospital might have service exits for doctors, nurses, patients, and other staff members. These should be provided for each floor served by a separate elevator.
The required number of exits are also divided into public and private areas. Public areas are those where the general public is allowed. These include entrances, lobbies, corridors, and parking lots. Private areas are those where only authorized persons are allowed including offices, treatment rooms, and storage facilities. These require a different level of security than public areas but can usually be accessed by anyone with authorization.
Public areas need to be cross-matched against possible threats. This means checking to see which doors lead outside and which don't. Some possibilities include ground-level doors, windows, and fire escapes.
(a) In the case of an emergency, every building or useable component of a facility must have at least two exits to enable for the timely evacuation of employees and other building occupants.
(b) For new construction, all buildings over 7,500 square feet (70 m2) must have at least one additional exit for each 10,000 pounds (4.5 t) of floor area exceeding 7,500 square feet (70 m2). Exits may be by way of staircases, fire escapes, and/or emergency vehicles. Doors must be clear of obstructions that would prevent an occupant from exiting quickly.
The National Fire Protection Association (NFPA) recommends that all facilities have at least two ways out for each room. If a fire breaks out somewhere in the building, people need to be able to escape easily without waiting for anyone else. The association also recommends that you provide fire extinguishers in all rooms, including offices, and that you test them at least once a year.
In conclusion, all buildings need two exits for each room to ensure employee safety in cases of fire. Additional exits are recommended to provide freedom of movement for people wishing to evacuate large areas such as floors or entire buildings.
Only one exit is necessary in a single-family house, and exits from a second floor or basement may proceed via contiguous rooms if the method of escape fulfills the code standard (stairs must meet minimum code at time of construction). If there are more than three floors above ground level, then multiple exits are required.
In other words, only one way out should be difficult or impossible under emergency conditions.
The American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) recommends that basements have two ways out: one from each floor above ground. The National Fire Protection Association (NFPA) suggests two ways out for basements. Both organizations recommend using caution not to create dead ends in hallways.
The NFPA also recommends fire doors to separate living areas from hallways and storage from cooking areas. Fire doors should be self-closing and lockable from both sides to prevent children or pets from becoming trapped.
Basement fires are most likely to start with smoking materials, such as cigarettes, cigars, and wood products. Keep cigarettes and other smoking materials away from kids and pets. Make sure to use ashtrays when smoking in the home. Basements are often used for storage, so keep toxic items out of reach of small children and animals.