Fire Alarm System
A fire alarm system warns people when smoke, fire, carbon monoxide or other fire-related emergencies are detected. These alarms may be activated automatically from smoke detectors and heat detectors or may also be activated via manual fire alarm activation devices such as manual call points or pull stations. Alarms can be either motorized bells or wall mountable sounders or horns. They can also be speaker strobes which sound an alarm, followed by a voice evacuation message which warns people inside the building not to use the elevators. Fire alarm sounders can be set to certain frequencies and different tones including low, medium, and high, depending on the country and manufacturer of the device. Most fire alarm systems in Europe sound like a siren with alternating frequencies. Fire alarm electronic devices are known as horns in the United States and Canada and can be either continuous or set to different codes. Fire alarm warning devices can also be set to different volume levels.
Essex (/ˈɛsɪks/) is a county in the East of England. One of the home counties, it borders Suffolk and Cambridgeshire to the north, the North Sea to the east, Hertfordshire to the west, Kent across the estuary of the River Thames to the south and Greater London to the south and south-west. The county town is Chelmsford, which remains the only city in the ceremonial county until Southend-on-Sea is formally accorded city status. For the purposes of government statistics, Essex is placed in the East of England region.
There are four definitions of the extent of Essex, the widest being the ancient county. Next largest is the former postal county, followed by the ceremonial county with the smallest being the administrative county – the area administered by the County Council, which excludes the two unitary authorities of Thurrock and Southend-on-Sea and the areas administered by the Greater London Authority.
The ceremonial county occupies the eastern part of what was, during the Early Middle Ages, the Anglo-Saxon Kingdom of Essex. As well as rural areas, the county also includes London Stansted Airport, the new towns of Basildon and Harlow, Lakeside Shopping Centre, the port of Tilbury and the borough of Southend-on-Sea.