For the world at large, Standards / Codes of Practices set out a generic good. It allows for knowledge-sharing and sets the expectation of performance. Balance thus needs to struck between preventing corner-cutting / the unscrupulous and not stifling innovation.
Sadly though, this sometimes creates holes for which pegs then have to fit. A round peg isn’t wrong for being a round peg, it just won’t fit through a standard square hole of the same area.
For the past 25+ years I have worked with some fantastic people and the best brains in the fire industry, be this colleagues, consultants, contractors as well as competitors who collaborate through the trade associations (such as the BFPSA / Fire Industry Association FIA).
I was fortunate to hold the right position when halon got its red-card and the replacements came through, including working on the BFPSA CoP which became a draft for BS DD 233 and was adopted as the basis for ISO 14520, which we now work to as BS EN 15004.
We thus need to understand what creates the Standard. Normally industry innovates, experience is gained then the trade will set to author a draft Standard which undergoes stakeholder improvement and ratification. Subsequent improvement stimulates revision, normally arising from catastrophe, better understanding and/or technological innovation.
For fixed gaseous fire fighting systems we essentially have three codes, ISO 14520 as the globalised norm, EN 15004 as the European ‘emulation’ of this and NFPA 2001 for the Americas.
Protection works on the premise that a fire condition is detected (be this incipient [smoking / pre-burn] or flaming, then a clean agent is deployed to put out the fire, or to prevent an incipient situation progressing to flaming combustion.
Since the origins of datacentres (DCs), challenges and expectations have evolved exponentially. In early days, cooling was interrupted and power isolated when a fire was detected. Nowadays such is unlikely, so the [retention] hold time – which used to remove the likelihood of reignition and allow for remedial (Fire & Rescue Service [F&RS]) intervention – is even more important.
Stakeholders need to consider what to do when a system operates to prevent restrike – or escalation – when the agent concentration is lost. This part is not prescribed in the Standards and sometimes overlooked in the bigger picture.
At the opposite end of the fire protection spectrum there are some system which strive for first-aid local-application flame knockdown. Direct Low Pressure (DLP) system – such as the LPCB’s Loss Protection Standard LPS1666 – perhaps limit themselves too much to this goal. Maybe the system constraints have been established through consensus of the OEMs whose system characteristics are known.
I have had pleasure of working with colleagues from Siemens Energy Management division and the wider DC Team and applying what I know of fire, and hear of industry concerns, I wonder if the Standards we specify perhaps prevent the ideal solution.
For instance, if a tube can be fed through energised electrical equipment, and if operated by fire this acts as the discharge pipe, then we have the DLP system. However, DLP is unlikely to achieve the hold time a fixed system is expected to under ISO 14520 / BS EN 15004. DLP also typically uses a synthetic agent such as Novec 1230 of HFC227 (or possibly CO2).
If we applied the approach of an inert gas – a cylinder containing “air without oxygen” – we can perhaps have something different and possibly better?
For the fire protection community, the inert gases we use are typically pure nitrogen, pure argon or blends thereof. Their primary extinguishing mechanism is by air displacement and lowering the oxygen to a level that will not support combustion.
For rooms and occupiable spaces, this reduced oxygen is limited for two reasons:
- Principally life safety. If it is human-safe, then the system need never be incapacitated (and therefore never accidentally left isolated); isolation = no protection!
- Cost. Whilst the agent is very cheap, filled cylinders are not, so keeping this to as few as possible has cost, weight and environmental wins.
Take a step back though and the cost different between a small inert gas cylinder and a large one isn’t very much. The agent cost itself is pretty insignificant.
So, if we now consider what a DLP system does – say protect some electrical switchgear – if we used a large inert gas cylinder and regulated the flow we can get a hybrid of LPS1666 and ISO 14520 / EN 15004 protection. The best of both worlds.
This can be low cost of capital purchase and install, and do away with the headaches of larger systems (detection and alarm, C&E, room integrity, etc).
Therefore, we could have a single 80 litre cylinder connected to a DLP type detection & discharge tube. Filled to 200 or 300 bar – the industry standard (so we are using high volume manufactured, standard, low cost) – technology, with a valve that throttles the flow to achieve the compartment flood in <60s – as in ISO 14520 / EN 15004 – but with such agent storage the cylinder pressure decay delivers in excess of the hold times the fixed system standards also would require. The residual oxygen within the switchgear may be too low for people, but switchgear isn’t itself occupiable and post fire the attending F&RS professionals know what to expect. A positive of localised very low oxygen, is the delay in natural reinstatement of oxygen to a level to support combustion within the offending asset / switchgear, further extending protection.
I am sure OEMs have already thought of this. Perhaps those making DLP don’t yet want to upset the room protection people or, conversely, the room protection people do not want to see many opportunities lost to far lower cost alternatives. Certainly, there are hundreds of thousands of Low Voltage (LV) switchgear panels globally which are without protection solely because of the cost and inconvenience of having a whole room system fitted. I believe the cost of this hybrid approach can make all those viable to protect – safeguarding the building and occupants around them.
So, what is preventing this innovation? Perhaps it’s just not having a Standard to which this can be done?!?
Standards: do they stimulate or stifle innovation?
Written by Chris DowningSiemens Smart Infrastructure