What does a large-scale fire protection project entail?
By Alan Josué Vázquez Zárraga*
Participating in a project whose objective is to guarantee the safety and integrity of people will always be a challenge that will not have room for any type of error, especially if it is a large number of people who must be insured.
Reducing the risks of a building being affected by a devastating accident, such as a fire, is an obligation that involves numerous technologies, standards and safety protocols. However, we have witnessed, for one reason or another, tragedies that make visible the importance of having an adequate fire protection system, such as the one that occurred in the Conagua building in Mexico City last year, or the unfortunate fire in the East Tower of the Central Park of Caracas in 2004.
Although in such cases there were no deaths or affectations that transcended the material, the economic losses represented by these events, among many others of the same nature, are usually millions of pesos, sufficient reason to pay greater attention to issues related to fire prevention and protection.
Passive and active systems
A fire protection system consists of both passive and active systems. While passive systems are those materials and procedures that are applied in constructions to reduce the possibility of fires (intumescent paint, fire-resistant finishes and materials, etc.), active systems are systems that require manual or automatic activation, and are divided into detection systems and suppression systems.
Detection and suppression systems
Detection systems use electronic devices to detect possible sources of fires, before which they emit an alert signal (smoke detectors and sprinklers controlled from a control panel); on the other hand, suppression systems are used to directly extinguish fires (fire extinguishers, pumping system with prefilled water pipe networks, sprinklers, preaction systems, foam systems, etc.).
In addition, it is important to have mechanical ventilation, that is, fan systems that allow the evacuation areas to be smoke-free in case of suffering a fire inside a building.
Renovation of the Scotiabank Tower
In SISSA Infrastructure, one of the three main divisions of SISSA (in addition to SISSA Digital and SISSA Monitoring Integral), we are dedicated to developing and implementing technological fire protection solutions for all types of environments, working on projects ranging from the simplest to the most complex, such as the integration of technological solutions that we will develop in the renovation project of the Scotiabank Tower, located at Blvd. Manuel Ávila Camacho 1, Lomas de Chapultepec, Migue Hidalgo, CDMX.
For this project, it is contemplated to implement in the core of the building two main networks: a network of sprinklers and a network of hydrants. However, it is also considered to implement foam systems for the helipad area, diesel tanks and a preaction system for the IDF's located in a basement and on one of the 21 levels of the building. In addition, this project complies with NFPA 10/13/14/20 regulations, as well as Mexican specifications and UL/FM approvals.
Pumping system
A set of two pumping packages that work independently is contemplated: one for the network of sprinklers and hydrants and another to feed the foam system in the helipad and the diesel tanks. Each of these packages are composed of an electric pump and a diesel pump as a redundant system in case the first one fails, both with a capacity of 500 gpm at 300 psi.
Spray
The sprinkler system is calibrated to activate its operation once they detect a temperature of 135°F, causing the glass bulb to break and a discharge of water from the network is generated, so that the pumps start automatically and the operation of the entire system begins.
Hydrants
The hydrants feature a 30 m long and 38 mm diameter hose, bronze chiflon, hose holder, 10 lb extinguisher and bronze wrench. The operation of these hydrants consists in that when the valve is opened the system detects a drop in pressure that initiates the operation of the pumping equipment with a flow of 100 gpm at 65 psi.
Foam system
The foam system is considered to act in cases where there is a possibility of fuel spills (such as the helipad and diesel storage tanks).
Mechanical foam is achieved by mixing air in a water solution containing a foam concentrate through properly designed equipment, allowing it to flow freely over a burning liquid surface to form a continuous blanket that excludes air and seals volatile combustible vapors; that is, leaving the fire without oxygen, suffocating it and extinguishing it.
Preaction system
Finally, the preaction system will be used in computer areas or where file information such as IDFs is stored, to avoid damaging both the information and the equipment that contains it.
This system uses a valve called a deluge and a network of sprinklers pressurized with air or gas, whose main function is to prevent an accidental discharge of water. The deluge valve will be filled with water when there is a risk alert, however, it will allow the exit of the water only if the smoke detectors confirm the possibility of fire.
It is important to mention that this project represents an important challenge for SISSA, since in addition to being a building of around 55 thousand m2 of construction, work will be done in its 4 basements, ground floor, 21 levels, roof and heliport without disabling its spaces, that is, working in a "living" building.
SISSA Infraestructura has a large team of highly trained professionals and uses the best technology on the market to provide first-class integration and implementation solutions, which adapt to the needs, requirements and possibilities of each of its customers.
* Alan Josué Vázquez Zárraga, Content Editor of SISSA Monitoring Integral
