Since MarcH the SSAIB haS been RUNNING a series of workshop and training days throughout the United Kingdom covering the implementation and use of DD243.
The training days have been extremely successful with both SSAIB members and non-members being welcome to attend and prepare for DD243. The initiative taken by the SSAIB to keep their members informed has been seen by the industry as a most useful exercise having attracted not only industry installation personnel but also police, manufacturers and insurers.
‘Industry taken back 20 years!’
Around 900 installers, surveyors and service personnel have attended the courses and a number of significant questions have been raised. Therefore in this article I will answer some of the most frequently asked questions.
The general feeling in the industry regarding the requirements of DD243 is that they have taken the industry back 20 years, particularly in terms of unsetting systems from outside the protected premises utilising shunt locks (More of this later). Also a major concern for many is that two of the unsetting methods most commonly used will disable all form of confirmation.
The most frequently asked question is:
This really depends on the needs and expectations of the customer. The first issue to tackle before decid-ing on the design of a security system is to conduct a structured risk analysis and evaluate the risk.
Dependant on the risk assessed you will then be in a position to complete a system design. DD243 states that one of the following is to be implemented:
a) An effective confirmation facility throughout the whole of the protected premises. The whole of the intruder alarm system should be designed and configured such that when an intruder enters any part of the protected premises:
b) An effective confirmation facility throughout specified parts of the protected premises. In this case the intruder alarm system should be designed and configured such that when an intruder enters specified parts of the protected premises:
The second most frequently asked question is:
For an intruder alarm system to be regarded as sequentially confirmed the intruder alarm system should be:
a) Configured so that at least two separate alarm conditions are reported, each originating from an independent detector within the confirmation time and,
b) the two detectors should be (i) different technologies or, (ii) same technology and not have overlapping areas of coverage. Two detectors of different technologies having overlapping areas of coverage are permitted to cause a sequentially confirmed alarm. However in the case of two movement detectors, at least one should be a dual technology detector.
It is permissible for two independent dual technology movement detectors incorporating the same two technologies to have overlapping areas of coverage. Individual movement detectors should be located to minimise the possibility of false alarms so careful consideration should be given to locating detectors where there are any overlapping areas of coverage.
Movement detectors should therefore be located some distance apart.
Even where there is no overlapping area of coverage, care should be taken to locate movement detectors far enough apart to minimise the possibility of sequentially confirmed alarms being false alarms (environmental conditions).
Where movement detectors are configured for the purpose of providing sequential confirmation, regular walk testing is important. To be regarded as independent, each detector should report alarm conditions separately to the control indicating equipment. The confirmation time – that is the time within which the two detectors are required to operate – should be not less than 30 minutes and not more than 60 minutes.
Not sequentially confirmed
Examples of configurations not regarded as offering sequentially confirmed alarm conditions are; two single technology movement detectors with overlapping areas, a double knock configuration, a dual technology detector, two or more vibration detectors with overlapping areas, two or more break-glass detectors with overlapping areas, two or more protective switches fitted to the same door.
The third most frequently asked question is:
Unsetting from outside the protected premises is now permitted using portable ancillary control equipment.
One of the most contentious parts of DD243 is the means of unsetting an intruder alarm system. DD243 permits a number of unsetting methods but care is needed in their selection as some of the methods disable all means of confirmation throughout the protected premises.
The following are the means of unsetting.
a) Unlocking the initial entry door unsets the whole or unsets part of the system facilitating the following:
