User Manual

Siemens Switzerland Ltd

Building Technologies Division

2. Fire protection in historical buildings

2.1. Fire basics

Awareness of how fires start and how they spread can help to reduce the risk of fire quite significantly. It is

common knowledge that it takes an ignition source, fuel and oxygen for a fire to occur.

The basic fire protection objectives are to try to control all three of these factors:

· Reduce the likelihood of fire by controlling potential ignition sources

· Minimize the potential effect by reducing the fire load (i.e. fuel)

· Inhibit fire development by limiting the oxygen supply

2.1.1. Controlling ignition sources

The probability of a fire occurring can be greatly reduced by managing the potential ignition sources and taking

appropriate preventative measures. As we have seen in Table 1 (above), a surprising number of damaging fires

have been caused during renovation work. In most cases this was a direct result of a lack of due care and

attention by the building contractors involved and a lack of appropriate supervision.

So-called “hot work” is the most frequent cause of fire during repair or renovation activities and includes the

following:

· Welding, brazing or soldering

· Cutting and grinding

· Paint removal using a heat source (blow-torch, hot iron etc.)

Such activities need to be regulated by a “hot work” permit system, which must be strictly enforced. Such activities

may only be carried out when all relevant fire protection measures are fulfilled: e.g. all flammable materials in the

immediate proximity are protected, the area is carefully inspected at the end of each hot work session and a fire

watch is organized (with a readily available fire extinguisher) that extends at least half an hour beyond the end of

the hot work session.

Other measures that should be implemented:

· Check all electrical installation and equipment and ensure that they meet current safety standards

· Portable heaters should not be used

· Electrical equipment should be switched off as soon as it is not being used

· Appropriate fire-proof metal containers should be provided for cleaning rags, cotton waste etc.

· Combustible materials and liquids (used in cleaning, painting, etc.) should be stored in appropriate

containers