Microtherm® solutions for fire safety.

Passive fire protection (PFP) – with Microtherm®

Fire protection has been described as a series of opportunities to intervene against a hostile fire.

These opportunities start with prevention by the selection of materials that will prevent fire spread.  Amongst these are common endothermic materials including gypsum board and concrete. These contain chemically bound water which absorbs incoming heat as a phase change occurs and the water becomes steam through the process of sublimation.  The steam is released from the material. Common sense dictates the use of non-combustible materials wherever possible.

Early detection of a fire is another fire prevention method that allows fast extinction by active fire protection systems. There are various stages of active fire protection - suppression and extinction according to the severity and duration of the fire.  The most common is a sprinkler system.

The final element of protection is containment of the fire such that evacuation of a building (or boat, train, or aircraft) can safely take place.  This is where the efficiency of Microtherm® insulation is invaluable.

The aim of passive fire protection (PFP) is to contain fires or to slow the spread, through the use of fire resistant walls, floors, and doors.  This fire resistance is conventionally achieved through either the protection of a surface insulation covering, or by an intumescent or ablative coating.

Passive fire protection systems require the very best thermal insulation performance for maximum protection duration.  The same principles apply whether the protection is for a building or for some form of passenger transport.  Passive Fire Protection, whether by insulation protection or a surface coating, is intended to contain a fire in the area where it starts and limit the spread of fire and smoke to adjoining compartments or rooms for a defined period of time.  As a system, it is likely to include a number of components such as fire resistant walls, ventilation dampers, fire stop doors etc., all individually fire rated and all interacting to achieve the desired level of protection.

Passive fire protection is also applied to the main structural components of large buildings with the objective of preventing building collapse before full evacuation can take place.


Hydrophobic flexible panels of Microtherm® applied as passive fire protection to a main structural beam of a large building in an exposed location.

The water repellency of the insulation allowed fast installation irrespective of prevailing weather conditions.


Microtherm® offers a series of products that are perfect for inclusion in passive fire protection systems combining the lowest thermal conductivity with non-combustibility. Our glass cloth covered microporous insulation materials are certified for zero spread of flame while being up to four times more thermally efficient than conventional insulation materials. All products are non toxic and maintain integrity through a fire exposure test irrespective of whether mounted vertically or horizontally. Microtherm® Overstitched flexible insulation panels achieved AI classification in the new European Single Burning Item (SBI) test, EN13823.  Because Microtherm® is the best performing thermal insulation currently available, all Microtherm® PFP systems are lightweight and extremely thin. The systems are also fast and clean to fit and easily examined during ongoing periodic maintenance inspections.  Microtherm® products will not deteriorate with time.

Insulation for fire rated lift shaft doors in building applications also benefits from a Microtherm® PFP system. Microtherm® Slim&Light panels are available in dimensions up to 2300 mm length, 500 mm width, and thickness varying between 15 mm and 30 mm which help to reduce installation time and cost. Microtherm® insulation makes elevator fire safety much easier to achieve.

In marine applications, Microtherm® PFP systems certified by See-Berufsgenossenschaft for aluminium and steel vessels for A60 protection to decks and bulkheads, meet in full both EU and USCG requirements. A Microtherm® "air gap" protection system is the lightest currently available. Microtherm® PFP systems have also been approved by the Maritime and Coastguard Agency for full 60 minute protection to both laminate and sandwich GRP composite vessels. Microtherm® contact systems are the thinnest currently available.


Microtherm® passive fire protection on the vehicle deck of an aluminium high speed ferry.

Railway insulation protection. The same Microtherm® benefits have been applied to PFP systems for rail applications and tested to ASTM E119 and the new European regulation EU 45/454.

Aerospace insulation designers also use lightweight Microtherm® systems for personnel protection. Microtherm® provides compact heat shields protecting the pilot from engine heat.

Although normally associated with protection of human life, passive fire protection is also utilized for the protection of valuable combustible items such as computer media and documents.

Microtherm® PFP systems have been successfully used in document safes and cabinets for general office use as well as for archival storage of valuable old documents at libraries and museums.

A fire safe represents the classic thermal challenge of the “closed box”.  Heat pours in from six faces with nowhere to go – it must all be absorbed by the contents and inner structure of the box.   For the most difficult performance specifications, the exceptional protection from the Microtherm® can be further enhanced by the inclusion of a phase change material (PCM) chosen for a transition temperature just below the safe exposure temperature of the contents to be protected.

Dataloggers both for industry and for event recorders for ships, trains, and aircraft (flight recorders, sometimes known as black box recorders) are made more compact and more efficient by the use of Microtherm®.   Voyage data recorders are now common on all forms of passenger transport.


Aircraft flight recorder.