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General Note on Suitability

The Automist range is an alternative to fire sprinklers with much lower water consumption. Its low water usage and rapid installation allow it to be used in situations where sprinklers are impractical. Automist projects fall into three categories:

  1. Automist Smartscan is used in a standard residential/domestic sprinkler applications (as per EW534).
  2. Automist Fixed Wall Head for Loft conversions (as per EW171).
  3. Nonstandard, custom projects where the use of a sprinkler system to enable the layout is not supported by guidance, but specialist fire engineering skills are applied to demonstrate that the appropriate safety level can be achieved using Automist in conjunction with other safety measures. Normally such projects will require a fire engineered solution based on the probabilistic risk assessement techniques of PD7974-7.

Some examples from these different categories are detailed in the following sections.

LABC Registered Detail for Smartscan

Automist Smartscan is an LABC Registered Solution (EW534) and is suitable to be used in any application where a BS 8458:2015 compliant watermist system is deemed to be acceptable as a code-compliant automatic water fire suppression system, for example in accordance with the recommendations of BS 9991:2015.

 Property Type


Required Automist Smartscan coverage

Common deviations
Not supported by guidance but in practice are sometimes approved where suitable fire engineering expertise justifies the deviation

Open-plan flat


A flat with habitable rooms, normally bedrooms, off one of the living areas, where the floor is above 4.5m from the ground outside.

BS 9991 sections 0.2.6 and 9.7 indicates that use of a suppression system throughout* can allow the creation of habitable "inner rooms".

Approved Document B does not provide detailed guidance; a common practice prior to BS 9991 has been to provide suppression to the open plan living area only, in cases where a probabilistic risk assessment indicates that this is appropriate.

Four- or more storey house

Houses with two or more floors that are more than 4.5m above ground level, where there is no alternative escape route from upper floors


A relatively common deviation is to allow some departure from full-house coverage in areas of the property unlikely to compromise the escape route, based on a probabilistic risk assessment.

Accommodation more than 45m from the road

Where a property is built more than 45m from the road



LABC Registered Detail for the Fixed Wall Head

Automist Fixed Wall Head is described in an LABC Registered Detail (EW171) for use in open plan layouts in loft converted houses in England and Wales. The Registered Details scheme allows UK building control officers to approve a project without a long and detailed investigation. Additional Registered Details are in development for new products scheduled for launch during 2015.

 Property Type


Required Automist Fixed Wall Head coverage

Common deviations
Not supported by guidance but in practice are sometimes approved where suitable fire engineering expertise justifies the deviation

Open-plan 3 storey house
(as described in Registered Detail EW171)

The ground floor area of a three-storey house has the living area open to the staircase.

Automist Fixed Wall Head coverage in open plan living area

In addition, the following are required:

  • A cut-off fire door to keep first floor clear of smoke
  • Escape windows at first floor
  • Kitchen separated by fire resisting construction
A relatively common deviation from Approved Document B is to permit the kitchen to be combined with the open plan area, in cases where this does not compromise the overall safety of the project.

Nonstandard Applications

These applications deviate signficantly from the guidance but are sometimes approved based on the application of fire engineering skills.

 Property Type


Typical Automist coverage
Must be judged on a case-by-case basis


Property without escape windows


A two storey house or bungalow where the windows are too small to be deemed an escape window, and the living area is open to the escape route from an inner room (for example a two-storey holiday cottage with open plan staircase).


Neither the building regulations nor BS 9991 mention this layout, however an equivalent layout is allowable for flats under BS 9991. The LACoRS guide also indicates in section 26.8 that fire suppression systems can in principle be used in lieu of a secondary means of escape; therefore where backed up by a risk assessment, existing rented properties may be able to use Automist to comply with the Housing Act and/or Fire Safety Order.

Open-plan 3 storey house with reduced fire separation

The ground floor area of a three-storey house has a living area open to the staircase and no fire door on the staircase.

Automist coverage in open plan living area

In addition, the following are generally required:

  • A cut-off fire door to keep first floor clear of smoke
  • Interlinked smoke detection throughout the property
  • Escape windows at first floor

A common criticism of the approach to open plan three storey houses in the guidance is that fire separation between ground and first floor by means of a fire door is ineffective because the door is likely to be left open. Critics further argue that the use of enhanced detection (i.e. in all rooms of the property) is preferable as it requires no human intervention. This layout may be accepted where a fire engineering argument demonstrates that, for a particular property, an appropriate level of safety is achieved.

Flat with no internal protected lobby or protected hallway

A flat where the entrance door from a communal stairwell or hallway opens directly into a living area

The room that opens directly onto the communal area

This layout is sometimes accepted when a building is being converted into flats, based on a probabilistic risk assessment.

Studio with kitchen by exit


This layout is commonly requested for student accommodation as it confers a better view to the living area of the flat

Entire studio area

This layout is sometimes accepted based on a probabilistic risk assessment.


* Note - BS 9251 defines fire suppression "throughout" as having the following exceptions:

  • bathrooms with a floor area of less than 5 m2;
  • [small] cupboards and pantries [with suitable fire protection]
  • non communicating, attached buildings such as garages, boiler houses, etc.;
  • crawl spaces."


Fire Engineered Solution

A custom fire engineered justification can be in the form of a "formal statement of suitability" or a "technical evaluation and fire development simulation". Fire safety engineering is a recognised method of achieving adequate fire safety in a building. It is sometimes the only viable method of achieving a satisfactory standard of fire safety in open or complex homes.

Fire Testing by BRE and Exova Warrington UKAS Laboratory

For the FIxed Wall Head, Plumis verified the effectiveness of Automist with live burns in a series of different scenarios. The test was based on BS EN 1869:1997, DD 8458-1:2010, and the criteria of Scandinavian SRSA/DSB "Easily installed automatic extinguishing systems". Critically, Fractional Effective Dosage (FED) measurements and "free burn" control tests were included to allow a complete and objective assessment. These tests were run in BRE Global's Watford (UK) Burn Hall and mimicked both furniture and kitchen fires.

The technical guide distils this fire test data into a useful tool for fire engineers and approval bodies (such as local authorities) to evaluate and accept Automist as a compensatory feature or where building regulations guidance proposes fire suppression.

The recent introductions of BS 9991 and PD 7974-7 illustrate the limitations of an approach to fire safety driven wholly by product categories; the new standards have a broader reach, allowing Fire Engineering skills to be applied to residential fire safety strategy, inherently embracing the use of Innovations in fire safety through rigorous analysis of limitations and solutions.

Automist Smartscan® has met the fire performance standards outlined in BS 9252 and BS 8458. Automist has also been tested in a range of realistic fire scenarios like oil pan fires, obstructions and shielding, to assess its fire fighting performance. In addition, Automist Smartscan® has been internally tested against all relevant UL 2167 clauses in preparation for listing.

BSi Verification Certificate

Independent third party confirmation (BSi Verification Certificate - VC 712581) issued that Automist Smartscan meets the performance requirements of BS 8458:2015 as verified in the Exova Warrington test report. As a fully UKAS Accredited Certification Body, BSI has always been at the vanguard of the testing and certification industry.


PAVUS is a notified body which carries out certification of fire protection products in the Czech Republic. Automist has been issued Certificate Number C-13-0072 E / S declaring it satisfies the relevant requirements of CSN 730873, CSN EN 12845 and BS EN A2 de 1869.

CE Marked

Automist has been tested and verified to meet the EU consumer safety, health & environmental requirements for the EU Low Voltage Directive (LVD) (2006/95/EC), Electromagnetic Compatibility Directive (EMC) (2004/108/EC) and Machinery Directive (2006/42/EC).