Visual Smoke Detection looks for smoke through surveillance monitoring detectors. Its analytics software identifies smoke behaviour and can be combined with flame detection technology. Temperature sensing technology is starting to be offered, for instance The Multi Detector, in the same solution.
Fire detection – the issues, costs and solutions that data centres operators need to consider and reconsider. Tony Smith business development manager for FireVu, has 10 years experience working with data centre industry professionals, gives us an overview.
As I was preparing to write this article a media report from Canada came to my attention. Two years after a data centre fire in Calgary disrupted essential services in the state of Alberta, it has emerged that recovery plans in the event of a repeat disaster are far from complete.
The 2012 fire affected hospitals, state registries and ATB Financial, the state bank. In October 2014, it is not known whether essential applications can be restored within 24 hours, tests are incomplete.
I don’t need to dwell further on the affects of a fire on server facilities for readers from the industry, but I might add that for privately owned data centre companies, in comparison to public sector organisations, the damage to a business’ reputation from a fire can be devastating.
Data centre fires though are thankfully rare – suppressants are highly effective once released.
A Google search will not reveal a litany of recent fires and their costly impact as you would find in other sectors such as recycling or manufacturing. Indeed this is partly why I took a current Canadian illustration and not one closer to home.
Nevertheless, saying that complacency should not be tolerated despite the low frequency of data centre fires.
False alarms (not fires) the scourge of the data centre manager
The costly challenge for data centre owners is the unnecessary release of suppressants: false alarms needlessly setting off sprinkler or gas systems can run into the thousands.
A single cylinder for many systems can cost £1000. So a large site can easily run up a £150,000 bill to replace the suppressants.
(Cylinder numbers vary, some clean agent suppressants such as FM200 generally have a lower number of cylinders compared to inert gas suppressants like Energetic but are more costly per cylinder).
The replenishment of the suppressants often takes 10 days to two weeks, so if a data centre wants seamless cover it would need a spare bank of cylinders. A costly and uncommon mode of operations despite the risk of not having undisrupted cover. Another option is a service exchange of cylinders, which will still leave a certain amount of down time and can also be costly.
Even if cylinders can be refilled with speed and additional cost, any period without full fire safeguards is unacceptable.
We should also mention that suppressants, though highly effective, have side effects.
There is potential damage from some suppressants, especially for many water based systems – if a sprinkler is activated water is released and the damage can be as costly a fire.
And they can be deadly, some systems such as Inergen (inert gas system) maintain enough Oxygen content to sustain life but reduce its content in the air sufficiently enough to douse the flames. Others use toxic elements that can affect the health of staff, clients and visitors.
The “double knock”
False alarms are in part reduced by the “double knock” as specified by BS6266 that ensures data centres have two signals before suppressants are released.
Pre-action systems for water sprinkler systems are advisable as they need to be activated by multiple alarms – a possible saving if it stops unnecessary use.
Yet, in my experience false alarms remain common occurrences and data centre managers experiencing multiple false alarms over the course of a year are far from rare. It is the bane of many a data centre operator’s life.
Fire detection solutions
Data centre managers have a range of fire detection technologies to select from that present different qualities.
Lets take a couple of popular choices:
Aspirating systems draw air through into a central detection unit from a network of pipes. The sampling chamber detects the presence of smoke particles suspended in air by noting the light scattered by them in the photoelectric chamber.
It is well-suited to clean rooms such as server facilities although ASD systems need maintenance, which can be performed in a non-disruptive way, to avoid getting clogged up. They cannot though differentiate between smoke and dust.
A key benefit of VSD is that fires can be verified visually, on site or remotely, before suppressants are released and so ensures everyone has left the server room and that unnecessary costs and damage are averted. Footage can be used during an incident to manage the situation or after to gather information.
While fires are not a regular occurrence and there is a wide choice of effective fire detection solutions and suppressants available, the issue of false alarms still remains an annoyance and a costly one. Data centre operators need to take this issue head on to avoid nasty financial surprises.
Tony Smith is happy to answer questions on 01928706422 or email@example.com
Featured in Data Centre Management magazine December 2014