Understanding the Differences Between Active and Passive Fire Protection Systems

Every building needs both active and passive fire protection systems to maximize protection. These two systems work together to stop and contain the threat of a fire. While each system can be effective alone, they offer the best combined protection.

An active fire protection system means that some form of action is being taken. This action can be manual, meaning that a person or people may engage in it, or it may be automatic, activating once fire, smoke, or heat is detected. Active systems are mainly designed to directly combat the fire and work to help extinguish it. An example of an active fire suppression system is what the fire department will use once they arrive. Most buildings are also equipped with active systems that can be deployed on-site in the event of a fire. These can include:

• Smoke detectors, which will activate with noise and light to alert the building occupants
• Fire extinguishers, which can be manually operated to help put out small fires
• Sprinkler systems, which will automatically activate to help put out the fire while building occupants move to safety
• Some ventilation systems, which help to direct smoke out of the building and away from occupants or areas where it may cause the most damage

Active fire protection systems are typically installed based on criteria such as occupancy and building size. For example, a specific number of sprinkler heads per feet will be required. It's also generally considered a good idea to add extra active systems in areas that may contain more sensitive equipment or have a higher than average risk, such as areas with flames or kitchens.

Many people believe that active systems are the best way to protect a building from fire. However, active systems have their limitations. While they can contain or suppress the fire, there are areas that they cannot reach. In such cases, the building could be at risk and the fire may spread beyond the control of even the best active systems. This is why including passive fire protection systems is crucial for comprehensive building protection.

Passive Fire Protection Systems

In a passive system, stationary materials are designed to prevent the spread of fire or smoke, containing the fire and preventing it from spreading throughout the building. When combined with an active system, a passive system can help extinguish a fire more quickly and minimize damage.

Passive fire protection systems are typically integrated into the building during construction. This can involve using fire retardant materials for the floors, walls, and ceilings of the building. These are made of materials you are familiar with such as brick, concrete, plasterboard etc

Other passive systems may be added later, after the actual construction of the building has ceased, such as fire-resistant glass partitions. These systems also include items like smoke and fire curtains, which can incorporate both active and passive elements. Fire and smoke curtains may deploy after a fire or smoke has been detected, and then become part of the passive fire suppression system.

Smoke curtains can be used in permanent positions at the tops of warehouses and other tall, open spaces. The objective of a passive system is to contain smoke and flames in one area or channel them out of the building. If smoke and flames are confined, they are easier to extinguish, fewer people are affected, it's safer for people to evacuate the building, and there's less equipment damage. It's recommended to install passive fire protection systems throughout a building. The use of flame-retardant materials in construction is advisable. Additionally, sensitive areas such as stairwells and lift shafts should have an additional layer of passive smoke protection, such as smoke curtains.

They must work together

Buildings ideally need both active and passive fire protection systems to maximise safety. Active systems can assist in evacuations and firefighting, but they have moving parts that can malfunction. For example, if sprinkler pipes freeze, they become inoperative. Therefore, it's important to also install passive systems throughout buildings.

Passive and active fire protection systems can work together to enhance building safety. For instance, passive smoke curtains can help direct smoke toward vents for removal, while passive materials can contain flames and smoke, enabling fire suppression systems to quickly extinguish the fire. Newer buildings are incorporating passive, flame-resistant materials, while older buildings can be retrofitted with smoke curtains and panels to enhance existing active systems.

Summary

Smoke detectors and sprinkler systems are important for detecting and controlling fires, it's the passive systems that physically block smoke and flames. By combining both types of systems, you can better contain and limit the spread of fire in your building, reducing damage and costs. Whether you're constructing a new building or updating an old one, it's important to incorporate fire suppression systems that work together effectively. Including both passive and active fire protection systems in your building design gives you the best protection against the threat of fire.