VdS-Schadenverhuetung Technische Pruefstelle

Part 2: VdS accompanies the development and spread of sprinklers

Working for fire protection with technical expertise

At the beginning of the 20th century, German insurers set the course for the systematic spread of sprinkler technology. In the years and decades that followed, the aim was to provide specialist support for the technical development and to define the conditions for its use.

Text: Hans Altmeyer, VdS Schadenverhütung GmbH

While sprinkler systems in England were already being inspected by employees of the insurers around 1900, Germany initially lacked a corresponding inspection body. In 1902, the general assembly of German private fire insurers therefore decided to entrust six recognized manufacturers with the inspection of the systems they had installed.

However, this self-regulation could only be a temporary solution, that much was clear from the outset. After all, there was the potential for massive conflicts of interest. After the first regulations for the acceptance and inspection of sprinkler systems came into force in 1906, the "Regulations for the Sprinkler Monitoring Service" were drawn up and in 1908 the inspection body of the private fire insurers began its work.

The testing of newly installed systems was soon joined by other tasks, such as the approval of manufacturers and the testing of technical components. The Sprinkler Laboratory at the Technical University of Aachen was responsible for this task, and its foundation was largely supported by the Aachener und Münchener Feuer-Versicherungs-Gesellschaft.

The sprinkler laboratory's good reputation spread across the European continent in the following years. In 1923, the laboratory received testing orders from Sweden, in 1925 from Moscow, and in 1930 it was entrusted with the regular testing of Danish systems.

There was also keen interest in the work of private fire insurers within the industry. This led to a representative of the public fire insurance companies also becoming a member of the Sprinkler Commission in 1912.

Premium discounts - a win-win situation

Discounts on fire insurance premiums were a strong motive for the use of sprinkler systems. Insurers were happy to grant them, as it soon became clear that the loss amounts were noticeably lower in sprinklered businesses. For policyholders, investing in a sprinkler system gave them the opportunity to save costs on an ongoing basis and at the same time significantly reduce the risk of business interruption and, often enough, complete ruin.

Initially, a discount of 25 % was granted if the sprinkler system was inspected twice a year. Without regular inspections, this was reduced to 20%. However, this model was soon abandoned and the discounts were increased significantly to between 40% and 60%, depending on the type of risk insured, and testing was made a prerequisite.

Additional fields of work

In the industry, however, technical development did not stand still, so more and more tasks arose that were sometimes more closely, sometimes only loosely connected to the topic of sprinklers. The insurers assigned these issues to the Sprinkler Commission, which was known to work efficiently. The commission therefore formed the Technical Committee in 1929, which dealt with current developments and their requirements.

In addition to sprinkler systems, the committee also dealt with other stationary extinguishing systems and fire protection equipment, such as CO2 and foam extinguishing systems. The committee did not limit itself to drawing up installation regulations, but also issued manufacturer approvals for these extinguishing systems. However, the testing center, which had since been renamed the "Sprinkler Testing Center of the German Fire Insurers", could no longer be involved in testing the systems - this was prevented by the outbreak of war in 1939.

A new start in 1945

After the Second World War, numerous loose threads initially had to be picked up again. All the files of the association and the examination office had been lost during the war. From a provisional office in Hamburg, the insurers in the West German occupation zones were therefore contacted and asked for the files on the risks insured before and during the war. With the support of several insurance companies, an overview was obtained, and in 1947 the examination office was able to resume its work - initially with just one auditing engineer.

The situation improved rapidly in the following years. By the end of 1953, the number of monitored sprinkler systems had returned to 243 - the same number as in 1927 throughout the old Reich. In addition, there were 50 stationary CO2 extinguishing systems and one foam extinguishing system.

The Sprinkler Commission was renamed the "Sprinkler and Technical Commission" in 1948 and increasingly focused on a holistic view of operational fire protection - for example, fire alarm systems were included, including concepts based on the newly emerging smoke detectors.

At the same time, more attention was paid to specific operational requirements and processes. As a result, dedicated regulations for painting companies, for welding work or for the storage of hazardous substances were created. In 1952, the sprinkler testing center, which was still based in Hamburg, was renamed the "Technical Testing Center of the Association of Property Insurers (VdS)" - or TP for short - to reflect its expanded tasks and competencies. This did not mean that sprinklers were lost from view: at the beginning of 1953, completely revised and updated regulations for the installation of sprinkler systems came into force.

New location, new opportunities

The move from Hamburg to Cologne in 1967 marked the beginning of a development in which core competencies were bundled at the new location. One of the most important measures was the establishment of the company's own laboratories. The existing laboratory at the Technical University of Aachen was so overloaded by the diverse type tests on components for burglar and fire alarm systems as well as fire extinguishing systems that it could hardly keep up with the incoming test orders.

From 1969 until the early 1970s, the laboratories for intruder alarm systems, fire alarms, high voltage current and sprinklers were set up in Cologne.

However, the premises at the laboratory location in Cologne-Ehrenfeld soon became too small, so that in spring 1976 the company moved to the premises on Amsterdamer Strasse in Cologne-Riehl, which VdS still uses today. Here, tests could also be carried out using new and improved equipment, which increased efficiency as well as the automation of individual processes, such as the recording of measured values.

In 1994, the laboratories - as well as the Technical Testing Center - were accredited by the German Technical Accreditation Body. As the sprinkler laboratory is now also notified as a state-appointed testing laboratory, it can also certify the conformity with European safety requirements required for the CE mark.

Trial makes perfect

However, extinguishing technology could not be tested on a large scale in the laboratories, and not all concepts could be evaluated at the desk.

This became apparent in the early 1970s, for example, when a new type of warehouse emerged in the logistics sector - the stacked rack warehouse, i.e. warehouses with pallet racking. The TP assumed that a sprinkler system in such warehouses, where sprinklers were only placed on the ceiling, was not sufficient for firefighting. In order to determine proven protection concepts for such risks, fire tests were carried out using the Minimax and Walther (later: Total Walther) fire houses. The results showed that additional sprinklers were needed inside the shelves in such warehouses.

This proved that TP was able to react very quickly to new situations and draw the right conclusions. However, this was not always without opposition. At the end of the 1970s, there were massive objections from the industry when demands were made to reduce the usual storage heights, limit the storage areas and create open strips between partial storage areas. As a result, large-scale fire tests were carried out by the Comité Européen des Assurances (CEA) - today: Insurance Europe - and confirmed the VdS findings.

In the years and decades that followed, warehousing and logistics proved to be an area of application in which sprinkler systems had to be constantly adapted to new developments. From the 1990s, for example, the automotive industry introduced just-in-time production based on the Japanese model, and other sectors adopted this concept. The fire protection challenge lay in the fact that polypropylene and polyethylene containers were increasingly being used in the associated warehouses, whereas PVC or metal had previously been the norm.

Once again, fire tests carried out together with the German Association of the Automotive Industry (VDA) provided clarity. As a result, protection concepts were published that included measures such as reducing storage heights, compacted sprinkler protection and the use of barriers.

However, it was not only new storage concepts that had to be taken into account, but also special storage goods that challenged tried and tested procedures. This was the case, for example, when the Dual System Germany began its work in the early 1990s. Suddenly, large quantities of combustible lightweight packaging arose that had to be collected and stored. Fire tests, this time carried out together with the Federation of German Industries (BDI), again provided clarity on how to deal with this situation.

Even tried and tested technology gets old

As reliably as sprinkler systems work, their components are also subject to ageing. As numerous sprinkler systems had already been installed for decades, not least due to the constant persuasion of the commission and the testing body, the testing of old systems after 25 years was introduced in 1999.

During the test, pipe sections were cut out and examined in the laboratory to determine the pipe wall thicknesses, and an endoscope was used to look inside the pipes. However, cutting them out was not an ideal method - which is why VdS soon switched to an innovative non-destructive method in which the wall thicknesses could be determined using an ultrasonic measuring device.

The very first tests showed that in dry systems, which are only flooded after triggering, there was more damage in the pipes than in wet systems.

The findings were not entirely surprising, as the inner surfaces of the pipes in dry systems are permanently exposed to the oxygen contained in the compressed air filling in combination with the moisture in the pipes.

Today, sprinkler heads are also randomly removed as part of old system inspections and tested for condition and functionality in the sprinkler laboratory.

In any case, the old system tests offered (and still offer) increased safety, as existing and impending damage can be detected before malfunctions occur in an emergency. The tests also provide information on the resistance of the materials used in different installation situations and can therefore also provide suggestions for further technical development.

Water mist extinguishing systems

Water mist extinguishing systems are related to the classic sprinkler system. Although they were invented as early as 1930, they were more widespread in Eastern Europe for a long time. In Germany, the technology came more into focus at the beginning of the 1990s, partly due to the ban on halon.

VdS has accompanied and continues to accompany the increasing spread and further development of these systems with fire tests, product and system approvals and is active in the corresponding standardization and guideline work.

The technical variants such as high and low pressure technology or systems with closed and open nozzles make this a challenging task, as does the fact that water mist extinguishing systems are not very fault-tolerant - even strong air currents can limit the extinguishing effectiveness. The design and proof of effectiveness of such a system therefore depend on numerous parameters that have to be simulated in tests. Thanks to the interaction between the technical test center and laboratories, VdS is also ideally positioned in this complex field.

Committees, standards and cooperation - national and international

The insurers' guidelines and regulations were soon also used nationally as a guide for authorities and other public agencies. In some cases, existing DIN standards were replaced by VdS guidelines, for example in 1985 with regard to foam, water spray and powder extinguishing systems.

In order to always reflect the current state of the art and technical discussions in the guidelines, the former association of property insurers attached great importance to cooperation with other players on the market. From the end of the 1960s, for example, this was promoted through participation in national and international committees, in the following years a permanent contact committee was established with the BDI, a regular exchange took place and still takes place today with the bvfa - Bundesverband Technischer Brandschutz as a manufacturer organization as well as with the expert network Vereinigung zur Förderung des Deutschen Brandschutzes (vfdb), from 1980 VdS participated in the "Fire Protection" working group of the Berufsgenossenschaft. VdS is also involved in national (DIN) and international committees (CEA, ISO, CEN) on a daily basis.

Close cooperation with international partner organizations has always resulted in the evaluation of product innovations. This was the case in the 1980s, for example, when ESFR sprinklers (Early Suppression Fast Response) were launched on the market with a water flow rate several times higher than that of existing sprinklers. Experience was exchanged with the laboratories of the US Factory Mutual Research Corporation (FMRC) and the British Fire Insurer's Research and Testing Organization (FIRTO).

Water mist systems achieve a high extinguishing effect with very small droplets (Photo: Marioff)

When the article talks about VdS, it refers to quite different organizations depending on the year and decade. Here is a brief chronicle: The Verband der Sachversicherer e.V. was founded in 1948 with the abbreviation VdS. It joined the General Association of the German Insurance Industry (GDV), which was founded at almost the same time.

In 1996, the VdS merged with the HUK-Verband and the Deutscher Transport-Versicherungsverband (DTV) to form the Verband der Schadenversicherer (VDS). In 1997, VdS Schadenverhütung GmbH was formed from the technical departments of the former property insurers' association with GDV as the sole shareholder.

Incidentally, the ESFR sprinklers are a good example of the constant updating of test procedures - special tests are currently being developed for this purpose. A real lighthouse project saw the light of day in 2003. After extensive preliminary work by the TP, the draft guidelines VdS CEA 4001 Sprinkler systems - planning and installation were published in collaboration with the CEA. It was intended to meet the requirements of the European market and help to standardize the guidelines for sprinkler systems at European level.

A revised version of VdS CEA 4001 is published approximately every three years; the current 8th edition was published in January 2024.

The guidelines are a symbol and tangible proof that from the first beginnings of sprinkler technology, an immense wealth of experience and convincing technical expertise has developed, which has decisively influenced and advanced the use of sprinkler systems in Germany and internationally.

From the sprinkler commission and the sprinkler test center of the early 20th century, a wide arc spans to the internationally renowned expertise that makes VdS, with its technical test center and laboratories, one of the leading players in the field of sprinkler technology and far beyond.