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Fully charged BS 5839-6: Changes to the recommendations for fire detectors in the principal habitable rooms of domestic premises
• sheltered housing, including both the dwelling units and common areas. Class of buildings considered as domestic premises by BS 5839-6 include, for example, bungalows, multi-storey houses, individual flats and maisonettes. It should be noted that for a building containing flats or maisonettes BS 5839-6 does not apply to the communal areas. For a full description of the class of domestic premises covered by BS 5839-6 see clause 1 (Scope). Changes relating to the type of detector
A revised edition of BS 5839-6, the code of practice for fire alarm systems in domestic premises came into effect on 31 May 2013. This 2013 edition does not constitute a full revision of BS 5839-6; however, it does supersede BS 5839-6: 2004, which has been withdrawn.
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t first glance it is evident that the Standard has been renamed. Compared to BS 5839-6: 2004, the title of the 2013 edition includes the addition of the words ‘commissioning’ and ‘domestic premises’, where the later replaces the word dwelling. The full title is now ‘Fire detection and fire alarm systems for buildings – Part 6: Code of practice for the design, installation, commissioning and maintenance of fire detection and fire alarm systems in domestic premises’. The Foreword of the 2013 Standard reveals that a number of the technical changes have been introduced, and one such technical change, the subject of this article, regards the type of detector recommended for installation in the principal habitable room of domestic premises. Other technical changes will be discussed in future Connections articles. Definition given in BS 5839-6 Principal habitable room – a room that is normally the most frequently used room for general daytime living purposes. Scope of BS 5839-6: 2013 BS 5839-6: 2013 applies to new and existing buildings used as domestic premises that are: • designed to accommodate a single family, • houses in multiple occupation that comprise a number of self-contained units, each designed to accommodate a single-family, and
For protection of life in new or materially altered buildings commonly used as domestic premises the information given in Table 1 of BS 5839-6: 2013 recommends that to provide the earliest practicable warning of fire to occupants, fire detection and fire alarm systems should incorporate a smoke detector installed in every principal habitable room. This is a change to the recommendations given in Table 1 of the 2004 edition of BS 5839-6 which recommended heat detectors should be installed in every principal habitable room. It should be noted that Table 1 of the 2013 edition still recommends heat detectors should be installed in every kitchen of new or materially altered premises. Detectors in principal habitable rooms As previously mentioned Table 1 now recommends smoke detectors are installed in every principal habitable room. Smoke detectors employed in domestic premises are generally of two types: optical detectors (OD) and ionization detectors (ID). Either may be used in the principal habitable room. However: • Optical detectors are less likely than ionisation detectors to respond to fumes from cooking. Thus, ODs are more suitable in rooms or areas into which kitchen cooking fumes may discharge. • Ionisation detectors are less likely than optical detectors to respond to tobacco smoke. Thus, IDs are more suitable in rooms or areas where smoking is likely. To limit false alarms, the response of ODs and IDs should not be overlooked when designing a fire alarm system. Unwanted alarms can have a detrimental effect on a fire alarm system, such as when the frequency of unwanted alarms results in occupants ignoring the fire alarm system signal (clause 12 (Limitation of false alarms) refers). Connections Spring 2015
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