Understanding the impact of fire or firefighting, and the signs of collapse, on the various types of structural elements and structural frames should assist in dealing with fires in buildings.
Risk assessments should consider the effects of the fire’s duration and intensity and of firefighting activity on structural elements or structural frames. Incident commanders should consider the tactical actions shown in the tables below.
| Structural element |
Tactical actions |
| Air supported structure |
- Due to the potential for collapse, consider the use of defensive firefighting techniques
|
| Arches |
- Consider the impact of fire (duration and intensity) or firefighting actions (use of jets) on the integrity of arches
- Consider the age and condition of arches
- Consider the potential effects of arch failure on the structure
- Monitor for signs of cracking, spalling or potential failure of arches
|
| Beams |
- Consider the potential effects of beam failure on the structure
- Monitor for signs of deflections or distortions in floors, indicating potential failure of beams
- Be aware that smoke may conceal signs of deflection or potential failure of beams
- Consider water cooling of affected beams to prevent collapse, having considered the properties of the structural materials used
|
| Columns |
- Consider the potential effects of column failure on the structure
- Monitor for signs of cracking, spalling or potential failure of columns
- Consider water cooling of affected columns to prevent collapse, having considered the properties of the structural materials used
|
| Connections |
- Consideration should be given to the type (for example, modern or historic) and condition of connections
- Consider the potential effects of connection failure on the structure
- Monitor for signs of connection failure
- Consider water cooling of connections to prevent collapse
|
| Floors |
- Consider the type and condition of floors involved in fire
- Consider the potential effects that collapse of floors may have on other parts of the structure
- Investigate floors involved in fire for stability and undetected firespread
|
| Load bearing walls |
- Consider the condition of the walls involved
- Investigate walls involved in fire for structural integrity
- Consider the potential of secondary collapse
|
| Lintels |
- Consider the potential for localised or secondary collapse
- Consider using alternative access routes to avoid potentially weakened lintels
|
| Trusses |
- Consider the type and condition of trusses, particularly if they have been involved in fire
- Consider the potential for localised or secondary collapse
- Consider the potential effects of trusses supporting decorative features, such as false chimneys and renewable energy systems
|
| Structural frame |
Tactical actions |
| Demountable structures |
- Due to the potential for rapid structural failure, consider the use of defensive firefighting techniques
|
| Masonry |
- Consider the age, condition and build quality of masonry
- Consider the potential for and impact of collapse, which can happen in the later stages of a fire or after the fire has been extinguished
|
| Modules |
- Monitor all adjacent compartments for firespread
|
| Portal or rigid frame |
- Due to the potential for rapid structural failure, consider the use of defensive firefighting techniques
|
| Steel frame |
- Due to the potential for collapse, consider the use of defensive firefighting techniques
- Identify whether steel has been protected from the effects of fire by cladding, and if so assess the condition of the cladding
- Assess what temperature the steel has been subjected to and for how long
- Monitor adjacent compartments or structures for conducted heat transfer
|
| Timber frame |
- Consider the presence of timber framed construction in new buildings
- Due to rapid firespread and the potential for early collapse in timber framed buildings under construction, consider the use of defensive firefighting techniques
- Consider the presence of concealed spaces and the potential for undetected firespread
- Consider the age and condition of the timber
- Consider the effects of the fire’s duration and intensity on the timber
|
