CHAPTER ONE
INTRODUCTION
1.1 BACKGROUND OF PROBLEM
Fire detection system are safety system. They monitor rooms and buildings continuously for indication of fire outbreak and give alarm directly if one occurs.
Both the British Factory Acts 1961 and the officers shops and railway premises Acts 1963 stiputed minimum requirements in the case of fire that there shall be clear and audible warning throughout the building. Also, an earlier statutory requirement (section 36[7] of the factories Acts 1937) states that in any factory, hospitals, market places, homes etc. Where more than 20 persons are employed that place should be effective provision for giving warning signal in case of fire outbreak and that it shall be clearly audible throughout the building.
STRUCTURE OF THE PROBLEM
The alarm is given locally (visually and audibly) in order to mobilize internal auxiliary personal e.g the works fire brigade) and inform them as to the seat of the fire. A control center performs the organization of the alarm, that is, it makes available operational aids for the fire fighting measures and automatically bring the fire protection equipment into operation. Fire detection system must be tailored to the geographical and operational conditions in each individual case fore detection system, and must be installed in accordance with the relevant regulations.
OBJECTIVE OF THE STUDY
In the past and present years now, there have been serious occurrences of fire outbreaks, each of which causes destruction of articles work millions of naira. In the past few months, there was fire outbreak in NITEL Exchange building at Apapa and Ikeja all in Lagos, destroyed materials estimated to be about N2.5 million.
These ugly situation of fire outbreak always result in frustration, instabilities and disconsolations to the individuals involved and the country at large.
It is therefore, on the recognition of this fact that we initiated the idea of constructing the fire alarm system, which is to alert the security men or fire service men in the event of any fire outbreak.
SCOPE AND LIMITATION
There are two main parts of fire alarm systems:
(a) The public fire alarm system
(b) The private fire alarm system.
The public fire-alarm boxes are connected to the fire station by dedicated lines. These alarms boxes also perform the function of relaying calls initiated from private fire detection system to the fire station automatically. The private fire alarm detections system are used to monitor particular limited properties. They are installed in among other places, offices and business premises, industrials and commercial undertakings, theatres, cinemas department stores, schools, old people homes, hospitals and hotels.
Fire detection system consist of the control centre including its power supply (mains equipment and battery) with the principal functions of indication control activating alarms and system management, the alarm units connected through call circuits, the monitored and unmonitored lines for controlling the local alarm and information equipment, the fire protection equipment and the circuit to the fire brigade.
Fire alarm units are in the form of automatic fire detectors or of press bottom alarm boxes. Base of these, we extended our attention on the form and nature of a fire alarm system that will give the desired result. Careful study was extended also to such areas as choice of components, portability, durability, economic choice and of course engineering efficiency. We also did our very best to ensure that the circuit wiring conformed with set standards with regard to requirements rules and regulations of electrical installation.
The position of the sensory unit of fire alarm system found convenient on the corridors, rooms, bath rooms or any strategic position where it is likely to be any fire outbreak. However, the sensory unit of the system should be kept at some convenient distance from the kitchen, because of the thermal characteristics of some of the relay component. Although, if installed in the kitchen should be well safeguarded against the heat that normally comes from the kitchen and should be at least 1.5 meters above the floor to avoid children’s reach.