One result of the recent trend toward open office environments is that smoke from office fires is not contained or isolated as effectively as in less open designs. Open office designs allows smoke to spread quickly and the incorporation of many synthetic and other combustible material in office fixtures (such as furniture, rugs, drapes, plastic wastebaskets, and vinyl covered walls) often makes "smoky" fires. In addition to being smoky, many synthetic materials can emit toxic materials during a fire. For example, cyanide can be emitted from urethane which is commonly used in upholstery stuffing. Most burning materials can emit carbon monoxide. Inhalation of these toxic materials can severely hamper an office worker’s chances of getting out of a fire in time. This makes it imperative for office workers to recognize the signal to evacuate their work area and know how to exit in an expedient manner

The vital necessity in layout planning is to provide a safe and easily identifiable means of egress for all the floor occupants by means of aisles to the exit stairs in case of fire or other emergency. It is absolutely vital that all aisles form naturally flowing paths and that they be continuously maintained free of all impediments. Furniture or furnishings including screens, coat racks, potted plants which may be upset under emergency conditions are to be kept out of the path of exit travel in the aisles.

Aisles are to conform to the following requirements:

Main aisles are to be provided on all floor areas to provide access to at least 2 exits, and arranged to minimize any possibility that both exit routes may be blocked by fire or other emergency conditions.
Subsidiary aisles are to be provided to give access to main aisles.
The travel distance from any point on a floor area to an exit, measured along the path of travel, including subsidiary and main aisles shall not exceed 40 m.
The travel distance from any point on a floor area to an exit, measured along the path of travel, including subsidiary and main aisles shall not exceed 45m, provided the floor area is sprinklered.
Main aisles are to be a minimum clear width of 1100 mm.
Subsidiary aisles are to be of a minimum clear width of 900 mm.
The maximum permissible length of a dead end aisle is 7.5 m.
Every individual work area is to be located adjacent to an aisle or subsidiary aisle.
Main aisles and subsidiary aisles are to be located to facilitate access to fire alarm pull stations, emergency telephone, first­aid and fire fighting equipment.
Main aisles and subsidiary aisles are to be continuously maintained and kept free from all obstructions.
All aisles are to be equipped with an illumination level of not less than 50 lx.
Floor layouts of main and subsidiary aisles are to be posted on all floors together with the Fire Orders for the building.
Walking surfaces are to be kept in good repair and free from tripping hazards.

Exit Marking
All exits doors, other than a main entrance to a room or building, are required to be identified by illuminated exit signs. Where such signs are not readily visible from main and subsidiary aisles due to obstructions, or when there is any possible doubt as to the means of egress, passageways shall be provided with a suitable arrow or pointer indicating the direction of egress.

Interior Finish Materials
The interior finish material has to conform to the Building Code,1995.

Interior finish includes that for walls, partitions of the fixed or movable types, ceilings, floors, and other exposed interior surfaces of buildings. It includes interior cladding of plaster, wood or tile; surfacing of fabric, paint, plastic, veneer or wallpaper; doors, windows and trim; lighting elements such as light diffusers and lenses forming part of the finished surface of the ceiling, and carpet material.

The characteristics of interior finish materials that are relevant to the fire problem are their ability to spread fire (flame spread rating), contribute fuel to a fire, and the quantity of smoke they develop (smoke developed classification) when burning. The generation of toxic gases as part of the burning process is also recognized as a life hazard.

Light Diffusers and Lenses
Diffusers or lenses must have a flame spread rating and smoke developed classification in conformance with CAN/ULC-S102.2-M88, 'Standard Method of Test for Surface Burning Characteristics of Flooring, Floor Covering, and Miscellaneous Materials and Assemblies'. The fixtures must also be designed so that the lens will drop out before it ignites when exposed to heat from a fire. The material must, therefore, also meet the criteria set out in the standard CAN/ULC-S102.3-M82, 'Standard Method of Fire Test of Light Diffusers and Lenses' as stipulated by the Building Code.

Screens and Partitions
Movable partitions or screens, including acoustical screens, must not have a flame-spread rating greater than the requirement for the interior finish of the area in which they are located. Movable partitions and screens must have a flame spread rating not exceeding 150 and a smoke developed classification not exceeding 300 when tested in accordance with CAN/ULC-S102-M89, 'Standard Method of Test for Surface Burning Characteristics of Building Materials and Assemblies'.

Floor Finish
Linoleum and vinyl asbestos tiles used as flooring materials have an excellent fire record. They have been rarely involved in office fires except under total burn­out conditions. In office areas in high buildings the flame spread rating of the floor surface must not exceed 25 and the smoke developed classification must not exceed 50.

Furnishings and Decorations
All furnishings and decorations, including curtains or drapes, artificial plants and other decorative material are required to conform to CAN/ULC-S109-M87, 'Flame Tests of Flame-Resistant Fabrics and Films'.