The surge in online retail sales post-pandemic has seen a remarkable rise in the demand for large, tall and clear warehouse spaces. These modern warehouses pose challenges due to increasingly complex storage arrangements, concentrations of values, combustible contents and physical limitations when it comes to firefighting.
With recent figures showing the average cost of a large warehouse fire is £5.9m1 and that 43 warehouse fires occur every month, businesses must consider the impact of fire and its consequences.
This feature looks at the changes to warehousing over time, the regulation gap and the need for effective methods to protect such buildings.
Wind back the clock to the early 1990s and the predictions of warehousing’s future were portrayed to me as one of large, tall storage spaces, full of automation and with very limited numbers of people. Stock would be pushed in one side and orders out of the other. Coming up to date I can see the large storage spaces and the growth of automation. When people discuss that advance in automation and robotics, they imagine spaces that have removed the need for staff. In fact, that is not what I observe, it is one element that surprises many. Even for cases thought to be highly automated there can still be hundreds of staff within the warehouse working with or around automated systems. It was typified for me by an incident at a large fulfilment centre when a fire occurred and nearly 2,000 staff left the building and congregated in a car park.
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Stage is set
The scale of these warehouses also continues to grow. The logistics sector needs a range of warehouses to fit its needs and those of its customers. Where some will focus on the ever-growing scale of certain buildings of 20,000m2 and beyond, with 50,000m2 under one roof not being unusual in new developments, others will be focused on the mid-range warehouse with recent industry observers noting the need for warehouses at or below 10,000m2 to service local communities. Putting these sizes into perspective, an average out-of-town DIY store is around 2,000m2. These warehouse buildings are five to 25 times larger.
At the heart of this is that the internal arrangements are changing too. The complexity comes in the form of the internal layouts and storage arrangements. The warehouse of today can operate on multiple levels: mezzanines, platforms, densely packed automated storage systems and handling machinery. These new arrangements present unique fire-safety challenges. At a basic level these arrangements challenge the fundamental ability of the fire and rescue service to access the building and the seat of any fire. At the same time, they are pushing the limits of what is possible with current fire protection technology.
Risk to lives and property
The basic hazards of a warehouse remain the same, large arrays of combustible material held in perfect arrays for burning. The complexity of some of the new storage arrangements have exacerbated this with ever denser arrangements. Whilst the fire load has increased with the use of plastics containers to offer regularised units to facilitate automated handling.
There are numerous examples that highlight that such conventional buildings pose a huge challenge in the face of a fire and need significant resources to contain. Even buildings far less complex and of much smaller scale are severely damaged.
A fire in Dagenham on 25 September this year required over 80 firefighters and 20 fire engines to tackle a blaze that broke out at a mixed-use two-storey warehouse. Firefighters prevented the fire from spreading to other buildings but could do nothing to save the 2,000m2 warehouse from burning to the ground.
On 29 August 2020, more than 100 firefighters and 20 fire appliances from Essex Fire and Rescue tackled a large night-time blaze at food distributor Kent Foods, based in Basildon. The fire and rescue service worked hard in arduous conditions but the 7,300m2 warehouse was destroyed.
The generation of warehouses today can be the same size with much more complex storage arrangements, higher fire loads and often larger compartments.
Regulatory guidance
When the latest regulatory guidance was written in 2006, it perhaps envisaged the design of warehouses differently. The Fire Safety Building Regulations (FSBR) guidance envisages unlimited sized industrial buildings. In the case of warehouses across Great Britain, this can be 14–20,000m2 in footprint and in many cases up to 18m tall, without incurring guidance for subdivision or sprinklers. Many are stunned to read this but remember the focus of the regulatory thinking is that the building is escapable, and people are protected. Ultimately the building is disposable in the event of fire.
These modern situations with multi-level structures, complex internal arrangements with large numbers of people upon them, were not on the cards in 2006. I expect to hear the normal refrain that these modern warehouses are not the ‘common building types’ envisaged by Building Regulations Approved Document B. However, this is a direction of change for these buildings that government needs to reconsider when reviewing the current English compartment sizes for warehousing and the guidance on the provision of sprinklers.
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Sprinklers’ active role
Sprinklers are an integral part of the fire-safety solution to protect such buildings. A string of people will now be shouting at this piece to tell me that ‘sprinklers are not a panacea’ and point to fires in North America and the UK as their evidence. However, when I consider the alternatives, manual intervention can make a difference but will not be reliable enough for all of these situations. Increased levels of detection may tell you something is happening, but unless there is rapid intervention the fire can still grow rapidly. The high levels of people in such a building makes the use of oxygen-lowering systems challenging, if not impossible for all but contained areas. Increased levels of subdivision of the warehouse into ever smaller compartments are at odds with the direction taken by the sector. Therefore, from a cost effectiveness perspective, the use of fire sprinklers makes sense as part of the solution.
The protective systems need to be designed to deal with the hazards created by the storage within the warehouse. This means early involvement in such projects to marry the available protection schemes into the storage design arrangements and liaison with the fire and rescue service. Trying to ‘just add protection’ is a recipe for a poor solution, particularly with sprinklers in dense storage arrangements. At the same time, manual intervention needs to be considered as any protection scheme will require the action of the fire and rescue services.
Every now and again someone tries to remove them and proves the point – the newly opened Gardman garden products distribution warehouse in Daventry being a good example of this in 2017. The building achieved a ‘Very Good’ BREEAM rating for its energy efficiency. Sadly, this was not matched in terms of resilience, as the building lacked active protection such as sprinklers. It was over 35,000m2 and relied on manual intervention to limit fire spread. The building was rapidly destroyed by a fire that had far-reaching consequences, just six months after it opened. The rebuild costs were placed at £30 million and the incident led to the eventual sale of the Gardman garden supplies business. To date, no rebuilding has taken place.
The fire-sprinkler systems for these warehouses are not a case of ‘fit and forget’. Like other such systems they need to be considered as part of the emergency response to a fire to ensure that they are maintained in service. Just like key parts of the warehouse systems they require inspection, maintenance and testing. If the systems are taken out of service for maintenance, then precautions are needed to handle ignition sources and repairs need to be expedited. Like any fire-safety arrangement, they need ongoing assessment to ensure the hazard they are protecting still matches their design. If it has changed then it needs to be recognised, considered and changed.
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Resilience
Whilst the complexity and commercial value of warehouses has changed significantly over the years, it has meant we need to work harder in order to protect them effectively through a range of solutions. This requires early collaboration with designers. The contrast between two buildings with and without a sprinkler system in a fire can be quite stark and a reminder of the need for effective protection. In the event of fire, many businesses with sprinkler systems suffer a minor interruption and find they’re back up and running in a matter of hours. Those without can see five to six times the damage and suffer longer spells of interruption.
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Decision makers consider the risk of fire is catered for by following building regulations when envisioning their new building, even though the guidance to those regulations is limited. Fire remains the largest cause of damage to such warehouse buildings. The number of industrial fires may have fallen but the extent and cost of those that continue to happen is increasing. However, they can be contained and extinguished by systems such as sprinklers to ensure that firefighters are not put at risk and businesses, jobs and the economy are protected.
For more information, go to www.business-sprinkler-alliance.org
References
1. Fears pandemic-led e-commerce boom could spark rise in warehouse blazes: https://www.zurich.co.uk/news-and-insight/fears-pandemic-led-e-commerce-boom-could-spark-rise-in-warehouse-blazes
About the Author
Tom Roche is Senior Consultant, International Codes and Standards for FM Global.
