12 Jan A complex network of systems and components
Visitors to any major city throughout the world will see some of the most beautiful buildings glistening in the sun with their seemingly endless matrix of reflective glass and trim. These massive structures are true engineering marvels both in terms of their breathtaking architecture and their powerful structural presence. What it took to design and construct these iconic masterpieces is nothing short of magnificent. While they stand strong and quiet in the midst of everyday life, high-rise buildings also pose unique challenges for the protection of their occupants. In his article, Len Swantek, Director of Global Regulatory Compliance, Victaulic takes a closer look at the complex network of fire safety systems and components and how each is maintained in accordance with local and regional codes.
On a macro-level, most modern building codes set minimum requirements for the use of individual components, systems and their materials of construction based on such factors as building type and height, occupancy type and occupancy levels and the fire-resistance ratings of building materials and the furnishings. Other known or perceived risks include environmental, natural hazards (weather extremes and potential seismic considerations) as well as proximity to heavily forested areas, where the spread of fire has had historical consequences. Interior wall panel and door construction, hallway and stairwell design, elevators and their protective concrete shafts as well as protective fire walls in major egress areas all have specific code and material specification requirements.
The water supply mains to the building, the sizing of fire pumps, the number fire protection risers and number of individual sprinklers required per floor or per room are confirmed through hydraulic calculations performed by the fire protection system designer and are checked on-site during construction by the local Authority Having Jurisdiction (AHJ), fire marshall or other authority working collaboratively with the building owner and their contractors.
All aspects of heat and smoke detection and the adjoining alarm systems must comply with local and/or regional fire codes and are tested thoroughly and frequently throughout the build. Emergency back-up power supplies must be properly located and have their own independent and often specialised compartmental fire protection systems.
High-rise buildings (typically defined as 23m, 75 ft and higher) require additional time for the building occupants to egress, as well as additional fire protection equipment like fire pumps and multiple sprinkler/standpipe risers to supply water throughout the building. Additionally, firefighters must have clear stairwell access to each floor. These systems and specific materials are also designed to protect the building structure to maintain its integrity in the event of a real a fire event.
The building codes require fire alarms; sprinkler systems; standpipe systems and sufficient water available to ensure that the fire protection systems will function properly. While the codes reference installation standards for these systems, the fire code and the installation standards also require that these fire protections systems are inspected, tested, and maintained on a routine schedule. Performing these inspections, tests, and periodic maintenance increases the reliability of these life safety systems.
The UAE Fire and Life Safety Code is one example of a requirement for the inspection of these systems. This code recognises that high-rise buildings have unique hazards and therefore require the most restrictive provisions and fire protection system requirements applied to all portions of the building. Since these buildings can have hundreds and even thousands of occupants employed in various businesses, as well as residential properties and hotels, it is common that the fire systems are equipped with multiple wet risers for redundancy.
The code will reference which installation standards are required. For automatic sprinklers a typically reference may include NFPA 13, Standard for the Installation of Sprinkler Systems. The wet riser systems for a combined sprinkler/standpipe systems will also reference NFPA 13 and NFPA 14, Standard for the installation of Standpipes and Hose Systems. The water supply for these systems will reference NFPA 20, Standard for the Installation of Stationary Pumps for Fire Protection, NFPA 22, Standard for the Installation of Water Tanks for Private Fire Protection, and NFPA 24, Standard for the Installation of Private Fire Service Mains and Their Appurtenances. The Fire Alarm will follow the requirements of NFPA 72, National Fire Alarm and Signal Code. NFPA 72 includes requirements for both the installation and the inspection, testing and maintenance.
Inspection, testing and maintenance
These NFPA codes will mandate that the systems are inspected, tested, and maintained in accordance with NFPA 25, Standard for the Inspection, Testing, and Maintenance of Water-Based Fire Protection Systems. While these requirements are the responsibility of the building owner, it is more common for the owner to delegate these tasks to a designated representative such as a fire protection contractor or private inspection services provider.
NFPA 25 specifies which inspections, tests, and maintenance (ITM) are required for each type of system. Here are some of the critical inspections required for sprinklers, standpipes, fire mains, fire pumps and water tanks.
The inspection, testing and maintenance of a building’s fire protection systems is vital to its performance for the life span of the building. These checks are conducted on a periodic schedule with notification to the tenants and business owners that specific systems will be tested and possibly in specific locations within the build and on a certain date and that alarms or other signalling devices will be activated as part of the inspection. When the occupants are notified in advance, there is a sense of assurance when a test alarm sounds in the hallways that the systems designed for their protection are working as intended.
However, and equally important, when these inspections and system tests are performed and any type of problem or malfunction is discovered, it is the responsibility of the inspector to ensure the affected component is removed and replaced with the same model or a model having the same performance ratings and agency certifications (ex. UL, FM, VdS and/or LPCB). The component manufacturers also play a role in these inspections by providing technical support for their product or system that is under review, which may require further corrective action. Depending on the age of the component, the inspector may require certain parts to be replaced throughout the building based on the criticality of the component and its overall function in supporting the complete system.
The inspections are certainly undertaken with great care and can be quite time-consuming when checking individual components throughout the building (as one example – control valves on each floor are tested for their supervisory function in the open position by closing the valve and confirming a signal is transmitted to the fire alarm control panel). It is this level of ongoing surveillance and system maintenance that most building occupants don’t often think about and may not be aware of. However, these procedures were established through the various codes to ensure safety as well as the protection of the building itself and the craftsmanship built into every detail.