Ch 19 485-485 concrete floors, wire cables

Sprinkler systems are often added last in a building project, with heads positioned after ceilings are completed.

Standpipe riser and outlets must reach within two floors of the highest point of construction.

Standpipes in cellars are used for drainage and must be manually shut off in emergencies.

Standpipe systems in buildings under construction are typically non-automatic dry systems.

Fire Department Connections (FDCs) are crucial water sources for fire fighting and should be clearly marked and accessible.

Floor outlet valves are often left open during construction, which can lead to operational issues.

The first-arriving fire unit should check the first-floor outlet; no water indicates a potential problem in the system.

Check each outlet as you ascend through the building.

An open riser top renders the system ineffective.

Riser sectional valves can create testing zones; closed valves render the system non-operational in that zone.

Buildings under construction have a higher risk of collapse due to incomplete structures and missing flooring or roofing.

Load-bearing walls are more stable than free-standing walls due to support from floors and ceilings.

Missing fireproof coatings on steel components can lead to rapid heating and structural failure.

Temporary steel bracing cables provide essential support but are vulnerable to fire exposure.

Heavy fires can threaten these cables, potentially causing extensive structural collapse if not cooled or evacuated promptly.

Tensioning cables in post-tensioned concrete are crucial for structural integrity but are vulnerable during construction.

Fire during the tensioning period can lead to catastrophic collapse if the steel is unprotected.

Poured reinforced concrete structures are very vulnerable to collapse when fresh concrete is curing, especially in the first 48 hours.

The weight of the unhardened concrete is significant and increases the risk of failure during this time.

Support structures like 4x4 wooden posts are essential while concrete cures, preventing collapse during the critical period.

After 48 hours, plywood formwork is removed, but floors must remain braced for 16-20 days after pouring.

Any fire in or above braced areas poses a high risk of structural collapse.

New construction methods often use aluminum posts and fiberglass forms, but the safety principles of required support during curing remain the same.

Disruption to supports can lead to catastrophic structural failures, especially during firefighting operations.

Sprinkler system heads are located on the ceilings for maximum coverage, but their installation is completed after the ceilings are built.

Standpipe riser lengths can be adjusted to suit the height of a building, allowing firefighters to access water sources at different levels.

While standpipe systems are generally dry during construction, they can be tested with water to ensure everything functions properly and that there are no leaks.

A crucial component of standpipe systems, fire department connections (FDCs) require clear markings and open access for firefighters.

During construction, floor outlet valves are often left open, which can lead to operational issues with the standpipe system.