70 HEALTH & SAFETY
Stand and deliver: the role of front-line fire monitors
While fire monitors spend the vast majority of their lives motionless and inert, when the call to action comes, their effectiveness can easily be all that stands between recovery and disaster. Far from being ancillary equipment, they are a ‘front line’ firefighting resource in volatile high-hazard environments. Peter Kristenson explains.
n essence, there are two types of fire monitor. The fixed monitor is a static appliance that is attached permanently to pipework and is positioned to stand guard over a specific fire risk, while the mobile monitor is most frequently employed to protect a multitude of fire hazards. As the term ‘mobile’ implies, they are trailer- mounted for fast deployment around the site so they do require a water supply, which is usually provided by hose connection to a hydrant or portable pumps. The decision to install fixed monitors or opt for mobile equipment is not as straightforward as it may first appear. Undeniably, a fixed monitor has the potential to be brought into action on a particular fire risk faster than a mobile unit that has to be moved and connected to a water supply.
I However, a major
petrochemical fire, for example, is often preceded or accompanied by an explosion with the potential to disable or destroy the fixed equipment before it has even had time to spring into action. So dependency on fixed monitors can be a high-risk strategy. Conversely, reliance on mobile monitors inevitably means some delay before firefighting can commence. It is also imperative
that all of the site’s possible fire scenarios are carefully assessed so that this delay is not extended while, for example, the most effective positioning of the monitors is determined. This requires careful fire planning to take into account the throw characteristics of the monitors, the proximity of hydrants, the need for hoses or pumps and possible wind conditions. Planning and training, therefore, are not options – they are essential.
Fixed and mobile monitors
Frequently, the best solution is a combination of fixed and mobile monitors, with fixed appliances acting as the first line of defence, and mobile monitors used to protect bunds, deal with fuel spillages and vapour concentrations, and to cool adjacent fire risks. Monitors can be operated either manually by the
firefighter or be remotely-controlled. Remotely-controlled monitors enable the firefighter to operate the equipment at a safe distance from the fire, moving the monitor in both the horizontal and vertical planes and, on the most sophisticated units on the market, adjusting the flow, stream pattern and throw. Power is hydraulic or electric.
Each system has
Fig. 1. The electric FJM-EL is remotely controlled, as is the hydraulic SKUM FJM-H.
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its particular benefits and leading equipment manufacturers offer hydraulic and electric options, as well as both manually-operated and remotely-controlled monitors. Electric remote control can be supplied with explosion-proof EEx (e) and flameproof EEx (de) electrical equipment in accordance with ATEX (ATmosphères EXplosibles) guidelines for when the monitor is likely to be used in areas that may be exposed to explosive gases. These ATEX guidelines apply in Europe and are similar to the USA’s NEC (National Electrical Code) guidelines.
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