Fire alarm and fire extinguishing.
I do not want to criticize the domestic regulatory framework in the field of fire safety. It is really far from ideal, but it is gradually improving. On the contrary, I want to note that there are sections of the notorious SP-5 that are quite clear and unambiguous — these are the sections describing the construction of fire extinguishing systems. Of course, even here it was not without a considerable lag behind the development of technology. I am not talking about the latest technologies such as finely atomized water or the features of the use of different gases. I am talking about integrated security systems. Everyone has been sick of it for about 10 years now: security systems must be integrated. What do we have with fire extinguishing?
The classic fire extinguishing systems described in SP-5 are intended for premises with special danger, for example with fire- and explosive-hazardous materials that need to be extinguished urgently, before the fire brigade arrives. These are serious premises in serious organizations. Or we are talking about extinguishing by areas — as a rule, these are sprinkler systems designed for installation in all premises of a large building in order to prevent the spread of fire. However, in modern conditions, with a high saturation of security systems with electronics and automation, very complex control algorithms are possible (and successfully implemented).
The first and obvious one is the connection between the security system and the automatic fire extinguishing system. It seems natural to turn on the automatic fire extinguishing mode when there are no people in the protected premises. Likewise, when there are no people in it, the premises must be armed. Is it reasonable to do this at the same time? Alas, not always. If the security system is really highly integrated and very advanced, so that arming and disarming occurs directly at the entrance to the premises, everything is correct, it is quite natural to simultaneously also turn on/off the automatic extinguishing. If the disarming of the entire building (or floor) is carried out from the security post, then it may not be entirely appropriate to simultaneously turn off the automatic fire extinguishing in all the premises of this building. However, turning off the security alarm in the entire building at once is also not good. So the question is which danger seems more dangerous to you — fire or theft.
If the security system is truly integrated, then arming (and therefore turning on the fire alarm system) is usually done under the control of the access control system. The first person to enter the premises also disarms it. The last person to leave, naturally, arms it. It goes without saying that the fire alarm system protects the premises while there are no people in it. But if there are people in the premises, they know better whether to turn on the extinguishing means.
The second point, which is not yet addressed by regulatory documents, is the fine control of extinguishing means. Fire alarms are almost universally addressable these days (I do not mean systems that are installed only to protect against a firefighter — there the solution is determined by the price, not by the operability). Addressable alarms provide very precise determination of the location of the fire. But fire extinguishing systems are still usually divided into very large areas. Okay, if these are huge production facilities — there, of course, even the most addressable detector will not help to accurately determine the location of the fire: the fire may be in one corner, and the detector near the hood will be the first to go off. But if your facility consists of many rooms, then it would be quite appropriate to consider each of them as a separate area of fire extinguishing.
Strictly speaking, even in a large room I once happened to see many directions of extinguishing. It was a salon selling expensive cars. Above each one there is a pair of flame detectors, and at their signal several clusters of powder modules are switched on — above this car and around. Thus, in case of a small fire, it may be possible to avoid covering all the convertibles with powder.
But let's return to a more realistic situation: an office building with many small rooms. A fire alarm (with direct signal transmission to the monitoring console) will call the fire brigade, and in 30-40 minutes, when the firefighters arrive, open the premises and roll out their hoses, they will successfully extinguish the fire, which by that time has spread to several rooms. Documents, goods, office equipment — everything is lost. Even if not from the fire, then from the foam with which they were doused. At the same time, cheap powder systems are quite safe (switched-off computers will survive, the information will not be lost) and quite effective. Even if they do not ensure the extinguishing of the fire, they will delay the development of the fire so much that the arriving team (or even the duty guard with a hand-held fire extinguisher) will successfully extinguish the fire with significantly less material damage.
Why do they still try to avoid installing fire extinguishing systems even in server rooms? A significant reason is that fire automatics are designed together with the building even before the owners (and especially the tenants) start planning the premises. And after the building is put into operation, installing a fire extinguishing system is very difficult — this means that a completely separate local new system must be installed, accordingly, someone must service it, and since it is not connected to the general fire alarm system of the building, the difficulties increase.
Is there a solution? Of course, there is. Most modern fire alarm systems designed for fairly large facilities are easily upgraded and expanded. Of course, the easiest way to upgrade an addressable system is to double the number of detectors in the required room, add one or more addressable executive modules that will initiate extinguishing, and, of course, provide control of the «powder, go away» signs, etc. Of course, the system, in principle, should be able to control extinguishing, this is not true for all systems, but we are talking about modern ones!
It is possible to upgrade some non-addressable systems, but in this case the beloved SP-5 definitely requires adding another alarm loop, which means that most likely it is necessary to install an additional alarm loop controller (and control) in the selected room and re-distribute the wires along the ceiling. Most likely, it will also be necessary to run a new communication line from the central controller (something like RS-485), and since such a communication line was not provided, then also install an RS-485 splitter. In general, the option, although more labor-intensive and probably more expensive, is also possible. Of course, the system must also be modern (it must not just be an alarm, but also be able to control fire extinguishing and at the same time allow for sufficiently flexible reconfiguration after installation).
So, why did I write this? Almost all new systems are not only developed using the latest electronic components, and therefore more reliable, more compact and cheaper than the old ones, but also provide more opportunities for developing the system at a specific facility. These opportunities should be used. In particular, one of the most promising ideas is to gradually, first in individual, most important rooms, expand the fire alarm system to a fire extinguishing system. Regulatory documents do not require this (they mainly talk about objects that are especially dangerous for others or about objects with defenseless disabled people and children). And this is right, the state must guarantee the protection of those who cannot take care of themselves. But I advise everyone else to decide for themselves what you want: to receive a signal about a fire (the state will again most likely only ensure that your building is extinguished before the neighboring ones catch fire) or to save your property.