Founded in 2010, DARZ GmbH is a full IT service provider offering top-quality colocation/housing, managed services and data centre solutions in an extraordinary environment under ideal security conditions at its data centre in Darmstadt. The data centre is located in the former vault building of the Hessian State Bank and has what is likely to be the highest on-site security level of any data centre in Germany: Erected in the late 1980s, the centrally located building with its striking white facade housed the Hessian State Bank’s gold and cash reserves from 1988 to 2005. DARZ GmbH sought to upgrade Darmstadt’s IT landscape by constructing a high-grade data centre infrastructure (TÜV Level III+/Tier 3+), true to its motto: “Data is worth more than gold!” When it comes to green IT, the overall concept, with its indirect free cooling, has already been awarded the 2015 German Data Centre Award in the “Overall Energy Efficiency in Data Centres” category.
The fire protection concept
Gaseous extinguishing agents which fight fires effectively without leaving residue are ideally suited to the IT sector. When fed into the extinguishing zone, the inert gas nitrogen displaces oxygen until there is no longer enough of it to feed a fire. As a natural component of the air we breath (78 % vol.), nitrogen is non-toxic and has a density similar to that of air. It is easy to store in extinguishing cylinder batteries and does not take up much space. When extinguishing is triggered, the nitrogen fills up the room quickly and uniformly without leaving residue or creating fog which impairs visibility. These are the reasons why WAGNER established a nitrogen-based FirExting® gas extinguishing system for the Darmstadt data centre.
But WAGNER’s protection concepts goes one step further: in order to effectively and reliably extinguish a fire within the shortest time possible, gas extinguishing systems must flood the area to be protected with extinguishing gas under high pressure. For this reason, conventional nitrogen extinguishing systems used to create sound pressure levels of over 130 db(A) from the gas rapidly rushing through the extinguishing nozzles, causing vibrations which can seriously damage hard disks. The indirect damage from this is often much worse than the fire damage itself – not only in the form of temporary server failures, but also due to data damage or loss. WAGNER solved this problem by developing special sound absorbers (FirExting SILENT with VdS device approval) which reduce the sound pressure to approx. 98 dB(A).
Flow regulators were attached to the extinguishing agent cylinders in order to minimise pressure spikes when the extinguishing process begins.This soft flooding device also considerably reduces the size of the pressure-release vents needed. This means that a single on-site F90 conduit system is enough to provide pressure relief for all extinguishing zones on the first basement floor of the DARZ. Only one opening to the outdoors is needed for the entire pressure relief in the first basement floor.
Active fire prevention via oxygen reduction was used in the hermetically sealed vault of the DARZ. WAGNER’s patented OxyReduct® system generates nitrogen from the air in the room and the ventilation system feeds it into the protected area, where it continuously reduces the proportion of oxygen in the vault to a heavily fire-retardant atmosphere. An oxygen level of 15.9 % vol. is below the ignition threshold of typical IT materials, so a fire can no longer develop or spread.
Receiving the VdS certificate as quickly as possible was an important goal for DARZ GmbH, a goal which was easily achieved thanks to WAGNER’s solution. However, the unique construction material used for the data centre made the DARZ something special for WAGNER’s project manager as well. Frankfurt branch manager Michael Leibner recalls: “We had never worked in special bulletproof concrete before that. The drillings we had to make in this extremely hard material were a real stress test for all the equipment we used. We also had to proceed with extreme caution. Staying on schedule under these conditions was a real challenge.” The Darmstadt data centre went into commission as planned in July 2014.