In the first chapter of Fire protection systems, You can read about types of sensors that are currently in use. Today we will focus on different systems arrangements of Fire Protection.
How to arrange sensors in Fire protection systems?
You know already which components are effectively detecting smoke and heat. Now is the right time to describe how fire systems are designed. The different fire protection systems are always built by sensors. The question is only how many sensors we need to protect the vessel? This depends on the spaces. The most common use system is to install a group of sensors that are divided into loops. Loops are placed in zones. A single zone is one deck or part of the deck divided by fire doors and firewalls from other equipment. This kind of configuration gives us double safety. In case of any technical issue or damage in one loop, other loops still stay active. The crew has time to repair issues and place them closely around are still protected. Not great, not terrible. Loops are connected to fire central, which is the heart of our system. From this place, we acknowledge alarms and manage fire fighting teams. These parts are the absolute minimum to run fire protection systems. Which is the fire alarm system.
In the picture up, is shown how proper place sensors at fire plan. Of course, in reality, the deck will have more space, more rooms, more doors, and more loops, but this is just an example. The whole drawing is the zone. In this zone, we have 2 loops created, blue and green. Colors are in use to easily follow the configuration and easier reed the graph. In both loops are different kinds of sensors, thermal and smoke detectors. 2 different types of sensors in accommodation, have to be used because of different usage of the compartment. In the smoking-room, the smoke detector will be not effective. The sensor will activate the alarm every single time when someone smokes a cigarette. In this case, is good to use the thermal detector in every room where smoke is allowed. Additionally, smoke detectors also will be not effective in the galley. Much better is to protect these areas by temperature protection. All other rooms and places are protected by smoke detectors.
Fire protection systems for Cargo Holds
Different kinds of systems You can use at cargo hold. Is it possible to use thermal and smoke detectors sensors, but there is also a solution with an air suction pump. The air pump is sucking air from cargo holds or different spaces and push it through the ultrasonic sensor. The unit is doing constant airflow analysis. If the unit can detect any changes and report them immediately. The big advantage of this system is that the suction point can be installed at the lower place. For example, if You have in 10 meters high cargo hold, suction pipes can be placed at a high of 3, 6, and 9 meters. By that arrangement, air can be sucked in different levels in cargo holds. This solution is very accurate and can be a really good solution for some types of vessels. How does it work? Look at the animation below. Air suction pipes are connected to the box with ultrasonic sensors. Every exhaust pollution which will be sucked from cargo spaces to the sensor will be detected by an ultrasonic sensor and a fire alarm will appear.
Other types of fire protection systems are active systems. More about these types of systems in the next chapter which You can find here!
Here You can find more details about procedures of fire extinguish at different type of cargo vessels.