Serverraum Serverschrank

Fire protection for server rooms

CO2 is not necessarily the best firesafety for server rooms. You can find out why this is the case and what is really useful here.

27 May 2021 Fire Safety

Just a few weeks ago, a major fire broke out at the large cloud hoster OVH from Strasbourg. A five-storey high data center with 12,000 servers, of which 4 server halls were destroyed. 3.6 million websites went offline at short notice. Some of the data was completely destroyed.(1) At the latest with such messages, it becomes clear again how important fire protection is.

Protect IT data and image

Server Festplatten

Whatever you want to call it, data center, computer room, server room or telecommunication room, no matter if there are one, three, ten or hundreds of servers... The access and use of IT data and systems are essential for today's business. This data, websites, clouds and co must be available and protected around the clock 365 days a year. If servers fail, this upsets customers, can damage the company's image and ultimately lead to lost sales. A holistic fire protection concept is extremely important, not only to protect the IT data and systems, but also the entire existence of the company.

Fire protection specifications

Buildings and their use are individual and therefore fire protection must also be considered and adapted individually by means of a risk assessment. Legal regulations, the building permit and the fire protection concept are the basis for finding suitable fire protection solutions. Additional requirements can come from insurance companies or be completed by voluntary measures of the owner or operator.

Holistic fire protection for server rooms

When determining the fire protection measures for server rooms, the entire building is considered and the structural, technical and organizational fire protection is taken into account. Not only the fire protection facilities such as escape and rescue routes play a role, but also the other technology such as air conditioning systems. The holistic fire protection solution takes the following stages into account:

  1. Fire prevention or fire avoidance
  2. Fire detection
  3. Fire fighting
Server Kabelverbindungen

1. Fire prevention or fire avoidance

To prevent or avoid fires, you need to know how fires start. For this, three things must come together at the same time as well as in equal parts:

Flammable material + oxygen + heat

This is the so-called combustion triangle or fire triangle.

Flammable material: The combustible material primarily includes the electrical cables that are installed for the servers, room lighting as well as air conditioning. Fire is accelerated by other materials such as cardboard boxes, IT accessories or documentation. Parts that are not permanently installed should not be placed directly next to the servers, but should better be stored in a fire-resistant storage room or in a steel cabinet. There should also be rules of conduct such as a ban on smoking or open flames.

Oxygen: In order for the fire to start and spread, it extracts oxygen from the air. To prevent new oxygen from being added, structural measures such as fire compartments, fire doors as well as extinguishing systems or oxygen reduction systems are useful.

Heat: Fire needs an ignition energy such as heat, mechanical sparks or electricity to start or to remain. Fire protection tries to minimize this energy, e.g. with an extinguishing system.

First fire protection measures

From this knowledge, the first fire protection measures are derived to prevent a fire from happening in the first place:

  • Structural measures such as fire compartments, fire doors or preventive measures such as the installation of an extinguishing system.
  • Possibility of reporting or self-help through fire extinguishers, fire detectors or also wall hydrants.
  • Regular control and sensitization for always accessible escape and rescue routes with appropriate marking, also in case of power failure.
  • Rules of conduct such as no smoking, no naked flames, but also training on how to behave in case of fire. By the way, at least 5% of the workforce must be trained as fire protection and evacuation assistants!
  • Regular inspection of the fire protection equipment in the building and, if necessary, adaptation during renovation by a fire protection officer.

2. Fire detection

When a fire breaks out, it is a matter of seconds to prevent something worse. The earlier a fire is detected, the sooner appropriate measures can be started. A fire alarm system with networked smoke and aspiration detectors is indispensable. If the fire alarm system is also connected to the local fire department, the latter is alerted directly. Other fire protection systems can also be connected to the fire alarm system. For example, the internal alarming of all persons present, the automatic closing of fire doors or gates as well as the triggering of extinguishing systems.

BMA Feuerwehr-Anzeigentabelau offener Schrank

3. Fire fighting

Once the fire has broken out and has been detected, the extinguishing measures can begin. In principle, several solutions are possible. Which is the most suitable for the server room depends on the protection goal and the size of the room, among other things.

Fire extinguisher

Nahaufnahme dreier CWS Feuerlöscher in Reihe

Only useful for very small fires / incipient fires. Carbon dioxide (CO2) is usually used for server rooms, as this does not damage the servers and other electronics such as air conditioning and electrical lines. However, CO2 is life-threatening to humans! CO2 belongs to the asphyxiation gases, if a person breathes in too much CO2, it leads to a lack of oxygen, which can result in death. Extinguishing with a CO2 fire extinguisher should therefore only be carried out if it is ensured that the fire protection assistant can flee the room very quickly or, in the best case, even extinguish from the open door and then close the server room, move to safety and wait for the fire department.

Automatic extinguishing system

Installing a self-triggering extinguishing system makes sense in any case. However, it is not possible to make a general recommendation because the size of the room as well as the respective protection goal are decisive for a recommendation. In principle, the following extinguishing systems are suitable:

Sprinkler system

Sprinkler system is the best known stationary water extinguishing system. The principle of operation is simple: a network of pressurized pipes and sprinklers runs through the server room as well as other parts of the building. In the event of a fire, the sprinkler system extinguishes the fire with water. The sprinkler is closed by a colored, liquid-filled glass tube, which is triggered at a temperature between 57 °C and 340 °C, depending on individual specifications, and releases water. The water droplets of a sprinkler system are approximately 1500 to 5000 µm (microns) in size. The water cools and extinguishes specifically, and the heat is removed from the fire. Disadvantage, the servers get a lot of water, whether they are still usable afterwards depends on the amount of water. The sprinkler system can therefore only be used to a limited extent.

Sprinkleranlage Wasserlöschanlage

Water mist extinguishing system

Water mist extinguishing system, or also called fine spray extinguishing system, has special nozzles and sprinklers that disperse water so finely that a water mist is created. The droplet size is much smaller than the sprinkler system, just 10 to 1000 µm (microns). This fine water mist distributes very well over the entire fire area. The resulting cooling and smothering effect ensures particularly effective firefighting with reduced use of extinguishing water. Compared to the sprinkler system, the amount of water used is much lower, which also greatly minimizes the damage caused by extinguishing the fire.

Wassernebel-Löschanlage Vernebelung einer Halle

Comparison sprinkler with water mist extinguishing system

  Sprinkler Water mist
Drop size 1500 to 5000 µm 10 to 1000 µm
Release time directly after hazard detection directly after hazard detection
Water distribution targeted extinguishing at the source of the fire targeted extinguishing at the source of the fire
Water supply high low
Water damage high low
Danger for people none none
Suitable for protection target
  • Protect people
  • Protect buildings
  • Protect environment
  • Protect facilities
  • Protect people
  • Protect buildings
  • Protect environment
  • Protect facilities
Maintenance at least annual maintenance at least annual maintenance


Stationary gas extinguishing system

There are different gaseous extinguishing agents, which are divided into three categories: Inert gases, chemical extinguishing agents and CO2. A gas extinguishing system is only useful for enclosed (server) rooms. It either displaces oxygen or removes heat from the fire. However, the gas concentration must be maintained for a specified time to prevent re-ignition of the fire. For personal protection reasons, an evacuation of persons in the protected area must be ensured before the gas extinguishing system is triggered. The delay time depends on the size of the room. Simply put, the person in the far corner of the room must be able to walk to the nearest escape door in peace. Gas extinguishing systems are the preferred technology for protecting server rooms, data centers and the like. Which gas extinguishing system makes sense depends on what is in the server room, what protection goal is defined, how large the room is and, above all, what is to happen to the servers and the like afterwards.

Novec-Löschanlage Gaslöschanlage

The following extinguishing agents are used in the three different gas extinguishing systems:

  • Inert gas extinguishing agents: Argon, nitrogen, IG 55 (trade name Argonite), IG 541 (trade name Inergen).
  • Chemical extinguishing agents: Novec 1230, FM-200
  • CO2 extinguishing agents: carbon dioxide

Comparison of gas extinguishing systems

  Inert gas

Novec 1230

FM-200 /

Extinguishing effect Oxygen displacement Extracts the heat from the fire Oxygen displacement
Release time

Delayed. Persons present must be warned by visual and audible alarms.

Delayed. Persons present must be warned by visual and audible alarms.

Delayed. Persons present must be warned by visual and audible alarms. Mandatory that each person is out of the room, as CO2 is toxic.

Gas distribution uniformly throughout the room uniformly throughout the room uniformly throughout the room
Gas supply

Much space necessary for gas cylinders.

Stocking in a separate room required.

Little space required for gas cylinders.

Stocking also possible in the protected area.

Medium size area necessary for gas cylinders.

Stocking in a separate room required.

Damage impact


Whether ventilation is sufficient or the gas must be extracted depends on the object structure.


Ventilation can remove the gas from the room.


The gas must be extracted from the room before it can be entered without a respirator.

Danger for people Risk of suffocation due to oxygen displacement

Harmless for humans

Very high! Danger of suffocation due to oxygen displacement
Possible protection goal Room and building protection Room and building protection

Machine or room and building protection

Maintenance at least annual maintenance at least annual maintenance at least annual maintenance


Halon no longer allowed

The use of halon as an extinguishing agent is no longer permitted due to the "CFC-Halon Prohibition Ordinance" of 1991.

Recommendation for server rooms

As already mentioned at the beginning, each building or use is individual. For server rooms, water extinguishing systems as well as gas extinguishing systems are fundamentally possible. Powder and foam extinguishing systems as well as aerosol extinguishing systems should by no means be used, the consequences of extinguishing would be too great as the entire electronics would be damaged. Both water and gas have their advantages and disadvantages. During the consultation, points such as building and room structure and the respective size, the protection goal and the extinguishing sequences are explained and carefully considered. A good fire protection solution for server rooms can only be found through a joint conversation, an on-site inspection or inspection of the documents.

Server schützen

Water mist extinguishing system

Daumen hoch - Das ist OK

Gas extinguishing systems

Daumen hoch - Das ist OK

Oxygen reduction system

Daumen hoch - Das ist OK

Sprinkler system

Thumb center - bedingt möglich

Foam extinguishing system

Thumb down - nicht möglich

Powder extinguishing system

Thumb down - nicht möglich

Aerosol extinguishing system

Thumb down - nicht möglich


Advice on fire protection for server rooms

We are happy to support you with the appropriate fire protection for your server rooms. We start with a conversation and an on-site inspection. Take into account the building permit, the fire protection concept as well as legal and insurance requirements. We advise and plan a suitable fire protection solution and send you a non-binding offer. We are happy to carry out the assembly and commissioning, prepare everything for a successful acceptance. You will then receive instruction on how to operate the system and we will be happy to carry out regular maintenance. Contact us now with no obligation to get to know each other and exchange ideas.

Do you have any questions about fire protection for server rooms?

You can find our data protection information here: Link
Hidden Fields

Source: (1)