1.3 Binary Relations
1.3.11 Quiz 5
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UNIT 4 SAFETY AND EMERGENCY PROVISIONS IN
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especially in mixed use premises and where unrelated occupiers, who live independently from one another, share common areas of the same building.
2.0 OBJECTIVES
At the end of this unit, you should be able to:
define safety in housing
enumerate reasons for the need for safety precautions in housing
explain safety and emergency provisions in housing
discuss method for carrying out a risk assessment in houses
explain the general principles of fire safety.
3.0 MAIN CONTENT 3.1 Definition of Safety
Safety according to Encarta dictionary refers to freedom from danger:
protection from, or not being exposed to, the risk of harm or injury or lack of danger, inability to cause or result in harm, injury, or damage or a place or situation where harm, damage, or loss is unlikely.
Safety in relation to housing refers to a situation and/or condition in a dwelling place of man where all facilities, equipments, devices and structures provided are placed and manipulated to support healthful living of man and the environment. It implies that all devices and equipments that can help to reduce hazards due to unforeseen situations and circumstances must be put in place and ensured that it is all working in perfect order. Such devices and instruments include safe stairs, dry and smooth floor, fire extinguishers, warning signs and labels, ample sources of light etc.
3.2 Reasons for the Need for Safety Precautions in Housing
A lot of resources are used to build up a house for self and family or for renting and take huge resources also to provide the facilities and equipments in the house. These facilities must be protected against all form of partial or total damage, therefore there is the need to provide additional resources to provide some services such as maintenance of electricity facilities, plumbing system, building structure and to also procure those devices and equipments that could be used to either prevent completely or reduce the negative effect that might challenge those planned facilities when there is emergency situation in the premises. Therefore the main reasons for providing these safety facilities among others are:195
to eliminate all forms of risks that has potentials for injury, disease or/death
to reduce, to the barest minimum, any damage or risk arising from failure of any system in the premises
to safeguard the resources invested in the premises so as to maximise its utilisation
to be able to have some form of alert that will help dwellers prepare or take measures against risks and dangers
You may wish to consider the reasons in the following way:
1. Moral
duty of reasonable care in the house
unacceptability of putting health and safety of residence/occupants at risk
society’s attitude to moral obligations of protecting lives and property
making the moral case to owners and managers of houses and estates.
2. Legal
the preventive (enforcement)
punitive (through criminal sanctions)
And compensatory effects of law.
3. Economic
Direct and indirect costs associated with incidents and/or unhealthy houses and their impact on the insurers, owners and managers (includes insured and un-insured costs)
3.3 List Safety and Emergency Provisions in Housing
Barry (1999), in “The Construction Buildings” discussed these provisions which is adopted here explained that fire safety regulations are concerned to assure a reasonable standard of safety in case of fire outbreak. The application of the regulations is directed to the safe escape of people from buildings in case of fire rather than the protection of the building and its contents.
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The requirements to the building regulations are concerned to:
3.3.1 Means of Escape
The requirements for means of escape from one and two storey houses are that each habitable room either opens directly on to a hallway or stair leading to the entrance, or that it has a window or door through which escape could be made and that means are provided for giving early warning in the case of fire. With increased height and size, where floors are more than 4.5 m above ground, it is necessary to protect internal stairways or provide alternative means of escape. Where windows and doors may be used as a means of escape their minimum size and the minimum and maximum height of window must be defined.
3.3.2 Smoke Alarms
To ensure the minimum level of safety it is recommended that all new houses should be fitted with self-contained smoke alarms permanently wired to a separately fused circuit at the distribution board. Battery-operated alarms are not acceptable. Where more than one smoke alarm is fitted they should be interconnected so that the detection of smoke by any one unit operates in all of them. Some mechanism should be developed for rural areas since the above may not be applicable.
3.3.3 Internal Fire Spread (Linings)
Fire may spread within a building over the surface of materials that encourage spread of flame across their surfaces, when subject to intense radiant heat, and those which give off appreciable heat when burning.
There is the need to have some classification of the performance of linings relative to surface spread of flame over wall and ceiling linings and limitations in the use of thermoplastic materials used in roof lights and lighting diffusers since we are yet to develop such in the country for now.
3.3.4 Internal Fire Spread (Structure)
The premature failure of the structural stability of a building during fires is restricted by specifying a minimum period of fire resistance for the elements of the structure. An element of structure is defined as part of a structural frame, a load bearing wall and a floor.
The requirements are that the elements should resist collapse for a minimum period of time in which the occupants may escape in the event of fire. Periods of fire resistance vary from 30 minutes for dwelling houses with a top floor not more than 5 m above ground, to 120 minutes
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3.3.5 Resistance to the Passage of Heat
Before the advent of oil and then gas as fuels for heating, it was possible to heat individual rooms by means of solid fuel burning open fires or stoves and people accepted the need for comparatively thick clothing for warmth indoors in winter.
With the adoption of oil and gas as fuels for heating it was possible to dispense with the considerable labour of keeping open fires and stoves alight and the considerable area required to store an adequate supply of solid fuels. With the adoption of oil and gas as fuel for heating it was practical to heat whole buildings and there was no longer the inconvenience of cold corridors, toilets and bathrooms and the draughts of cold air associated with open fireplaces. The population increasingly worked in heated buildings, many in sedentary occupations, so that tolerance of cold diminished and the expectation of thermal comfort increased.
Of recent years the expectation of improved thermal comfort in buildings, the need to conserve natural resources and the increasing cost of fuels have led to the necessity for improved insulation against transfer of heat. To maintain reasonable and economical conditions of thermal comfort in buildings, walls should provide adequate insulation against excessive loss or gain of heat, have adequate thermal storage capacity and the internal face of walls should be at a reasonable temperature.
For insulation against loss of heat, lightweight materials with low conductivity are more effective than dense materials with high conductivity, whereas dense materials have better thermal storage capacity than lightweight materials.
Where a building is continuously heated it is of advantage to use the thermal storage capacity of a dense material on the inside face of the wall with the insulating properties of a lightweight material behind it.
Here the combination of a brick or dense block inner leaf, a cavity filled with some lightweight insulating material and an outer leaf of brick against penetration of rain is of advantage.
Where buildings are intermittently heated it is important that inside faces of walls warm rapidly, otherwise if the inside face were to remain cold, the radiation of heat from the body to the cold wall face would make people feel cold. The rate of heating of smooth wall surfaces is
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improved by the use of low density, lightweight materials on or immediately behind the inside face of walls.
The interior of buildings is heated by the transfer of heat from heaters and radiators to air (conduction), the circulation of heated air (convection) and the radiation of energy from heaters and radiators to surrounding colder surfaces (radiation). This internal heat is transferred through colder enclosing walls, roofs and floors by conduction, convection and radiation to colder outside air.
3.4 Suggested Method for Carrying Out a Risk Assessment in Houses
The process can be broken down into five steps:
identify fire hazards
identify people at risk
evaluate, remove or reduce risk and protect against remaining risk
record, plan and inform or train
review.