12 Jan An evolution of risks & solutions
The humble warehouse has gone through many changes in the past 20 years; some obvious and others more subtle, yet more profound, in terms of the risk to a business operation. It is perhaps time that as fire professionals we stop to take another look at these key parts of a global business and economy suggests Tom Roche, Assistant Vice President, Senior Consultant, International Codes and Standards, FM Global.
The most obvious changes in warehouses are the physical dimensions as they become larger. The 20,000m2 warehouse is not uncommon. At the same time, taller than 15m has become the typical height of these buildings in Europe. In fact, as material handling system have advanced, so have the storage configurations which has led to even greater heights becoming possible, with some warehouse buildings reaching over 30m tall. These physical changes lead to some obvious fire challenges merely from their sheer size and storage configurations. At the same time there is the large financial risk which is present in the accumulations of stock.
However we should closely consider how business is changing over time and how this has driven the direction of warehouse operations and their growing importance throughout commerce and industry.
For many companies, warehouses are continuing to perform the traditional roles of storing, consolidating and shipping products but the speed at which they perform these functions has, in a number of cases, become an integral part of the business in order to live up to their unique selling point and keep their customer promises. This is not just in the business-to-consumer space but also within the business-to-business sector. If you stop to think about the trends in spending and our desire to have items next day then the former is easy to see. However this is also happening in the business-to-business space where companies are spread across a country or even several continents, run with reduced stocks and need to be more nimble in operation. Strong logistics and suppliers become key in their strategy and the ability to deliver promptly, locally and globally is vital.
To do this there has been an increased use of automation, and staff, to facilitate the movement of stock, the speed of transactions and the level of tasks grow. The risks to a business are potentially growing too, as it is not just stock at risk but key services that generate their profits and differentiate them in their chosen markets thus the need for resilience in these warehouses becomes ever more important.
However these changes have not lessened the key threat of fire. It still continues to be the leading cause of property loss. We still face the challenges of large amounts of combustible materials stored in configurations that, once ignited, burn rapidly and in fire terms are ideally arranged to sustain a large fire. Given these facts; the growing importance of these warehouses to business, the continued fire losses and the business risk, the exponential need to consider effective fire protection is very clear.
Automatic fire sprinklers still provide the most cost-effective solutions to the protection of warehouses. Their ability to effectively provide water onto a growing fire to control its spread, damage and most vitally the interruption to operations is proven over many years. In a warehouse environment these factors are vital to avoid a fire that will quickly grow beyond the capabilities of local firefighters. Recent research into the UK warehouse industry showed that over the life of a building, considering the threat of fire and the potential loss scenarios, sprinkler protection is cost beneficial in warehouses with a footprint greater than 2,000m2.1
That said the need for flexible space by logistics operations and increasing storage heights are pushing the limits of fire protection. Fire research is our best way forward to understand these challenges and bring forward cost-effective solutions. We have already seen the development of larger orifice sprinklers operating at higher flow rates to provide protection with the system located at the ceiling alone. These solutions can now provide adequate protection for warehouse buildings up to
As rack structures reach ever higher another technique is needed. Here the locating of the sprinklers within the rack structure is a very effective option, we call them in-rack sprinklers. By bringing the sprinklers into the storage array it allows them to operate more quickly and by careful placement, we can ensure that the growth of a fire is stemmed and damage reduced. This requires the in-rack sprinklers to be provided at regular vertical intervals within the racking typically every 3 to 6 metres.
Here again research is highlighting new cost effective solutions. The use of cutting edge computer models, intermediate-scale experiments, as well as full-scale fire tests at our Research Campus in the US has shown the way. This research has demonstrated that use of the same large orifice sprinklers but now used as in-rack sprinklers has been shown to be highly effective. Allowing us to increase the vertical intervals to 9 to 12m. Reducing the number of sprinklers that need to be installed, thereby cutting the cost of a system by as much as 40 percent.
As we continue to stretch the envelope of storage heights and configurations we will have to continue to develop differing techniques and configurations for fire protection. We will need these to be able to offer solutions to business to enable them to be resilient against the threat of fire. It will lead us to consider new sprinkler technologies and combinations of detection technologies to meet the challenge. One things is very clear and that is that research will continue to be vital to enable us to provide these cost effective solutions.
1. “An Environmental Impact and Cost Benefit Analysis for Fire Sprinklers in Warehouse Buildings” – BRE Global 2013
2. FM Global Property Loss Prevention Data Sheet 8-9 – Storage of Class 1,2,3,4 and Plastic Commodities