Modern African agriculture is a long way removed from the pastoral idyll. It is mechanised, large in scale, and often integrated vertically to store and process foodstuffs and other products. Like any industry or business, the premises, machinery and, above all, the people involved in this work require protection from fire. From a detection point of view, there is a problem; the environments that must be protected are extremely harsh.
What do we mean by this? From a fire detection perspective, an environment is harsh when it is dusty and dirty, there are airborne chemicals or vapours, it is humid, or the temperatures are extreme. These conditions are beyond the standard testing parameters for detection equipment, and therefore reliability and product lifespan are adversely affected.
At the same time, elements like dust and vapour naturally conceal smoke and/or threaten to trigger false alarms, making detection particularly difficult. While all of this is true for agricultural operations everywhere, it is fair to say that it is doubly true in Africa, which has many environments where temperature, humidity and dust are notoriously high.
ASD is the best choice
Anyone designing a fire protection system for an African agribusiness will therefore need to consider their choice of detection method and system design carefully. Despite the complicating factors, where possible, aspirated smoke detection is still the best choice for those who view early detection as a genuine chance to stop a fire in its tracks and save lives, businesses and assets. This is because most fires start as a smouldering, smoky affair that does not produce detectable flames or heat.
If a fire incident can be addressed at this incipient stage, it is far easier to put out, and little damage will have been done. A typical development curve of a fire sees a relatively long incipient stage, but once flames develop, they spread rapidly and become very dangerous and destructive. This exponential curve is often compounded in agricultural settings by the presence of dry, combustible goods, machinery and fuel, among other hazards.
Advanced linear heat for special applications
When confronted with a rough environment, one option is to forget about detecting smoke and focus on heat. While simple point-type heat detectors are also prone to premature failure in challenging environments, many linear heat detection systems on the market are effectively sealed and are, therefore, largely immune to dust and humidity – at least at the point of detection. Of course, when the African sun hits the thin corrugated roof that your line-type heat detector is positioned under, the detector’s algorithm will be inclined to conclude that there is a fire and sound the alarm, but such issues can be planned and accounted for. Indeed, sensitive systems with smart algorithms such as Securiton’s SecuriHeat ADW are adept at recognising these temperature spikes.
SecuriHeat ADW has been used successfully by Securiton’s partners in South Africa, for example, at a soybean processing facility. Its sealed metal tubing can even take significant abrasion, and it can be installed inside grain silos. It is also popular in food processing and production when the requirement for high hygiene standards means that the area is cleaned with pressure, steam or chemicals.
ASD for general early warning
However, many agricultural settings are suitable for aspirated smoke detection, allowing fire protection designers to aim for a much earlier intervention. This is particularly important in food processing and storage operations where crucial food supply chains would suffer should a total loss to fire occur.
For example, agribusinesses which have a key seasonal operation are required to process crops at harvest time, which would be left to rot if the service was unavailable. These operations often run at absolute capacity at these key times, which inevitably increases the likelihood of a fire from overworked machinery or people.
Protecting the food supply chain
In a typical seasonal fruit processing operation, for example, Securiton’s South African partner was faced with a site that operates virtually 24/7 during harvest time in November and December when the fruit is packed and dispatched for export. The farm required an effective and approved fire detection solution to satisfy its insurance company and protect its workers and assets, involving high-sensitivity detection to ensure early warning in the event of equipment or product fires.
This required a specialised fire detection system to cover the risks effectively. Devices that combine reliability, sensitivity, and an ability to survive tough conditions must be chosen.
The Securiton ASD range of aspirating detectors was identified as the best-suited solution for this section. Its five-stage alert and alarm system means that it can be operated at high sensitivity. Should a potential incipient fire be detected, staff can rapidly check and tackle it. This early intervention would preserve operations which, should they be rendered temporarily unusable by fire damage, would see the entire annual operation of the business grind to a halt.
Heavy-duty ASD required
From a fire protection perspective, meat and poultry processing plants can also be challenging. In another South African example, SecuriSmoke ASD535 HD devices are installed in one such factory’s cold storage, fresh chiller, plant room and dispatch areas. This heavy-duty ASD suits areas with large amounts of dust and moisture.
Water retaining boxes restrict moisture from entering the dust filters and sampling chamber to limit blockages and faults in the system. Additionally, heated sampling points on the pipe network in the cold storage applications prevent icing up, while SecuriSmoke detection and control units can be installed inside the deep freeze to avoid condensation problems associated with using ASD across two distinct temperature areas.
Finally, ASD systems are proving popular on farms to protect both animal sheds and barns where valuable and important equipment is stored. Animal sheds, in particular, benefit from an ASD system that is robust enough to handle the associated dust and dirt, because temperature detection is too slow to allow farmers to save their livestock. Such use of ASD in animal sheds and barns is becoming commonplace in Europe, where some countries mandate it on animal welfare grounds, and the usage has proved that aspirating smoke detectors can be highly effective in preserving not just animal lives but farmers’ livelihoods, too.
Typically, SecuriSmoke SDS 535HD with dust filters and sometimes dirt traps is used. Securiton expects increased use of ASD across the African agricultural sector as more fire safety professionals recognise the advantages of early warning fire detection.
For more information, contact Securiton
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