Ever since the Duncan Dock Cold Store fire over 20 years ago we all know that freezer stores can burn. Various types of sprinkler systems have been installed in freezers at great expense and questionable efficiency. Broken sprinkler heads lead to condemned product and disrupted operations until ice can be cleared from the floor.
But there are alternatives, one of them being to reduce the oxygen level within the freezer store so that fires simply cannot take hold. Discussions with Arina Duyvesteijn of FX Prevent suggest that a nitrogen production system to reduce oxygen percentages from 20 to 15% in a Cape Town freezer store measuring 53.8metres X41.3 metres X 15 metres high holding 6000 pallets on mobiles and a high volume throughput through 2 full sized doors would be 374,600 Euros installed.
The use of conveyors for introducing and dispatching product with full sized doors only opened to allow for reach truck end of shift movements could reduce the capital cost by almost 28%.
Running costs, largely for the FX prevent compressors, with large doors approximately 21000 KWhrs per month. Small doors with conveyors 10,000KWhrs.
Special attention would be required around the sealing of panels but this, like keeping access doors closed, should already be common practice to reduce energy costs.
At 15% oxygen personnel could still work safely inside the freezer but would need to be trained in the relevant health and safety aspects.
While I have no idea on the current costs of a sprinkler system for the same size of store, especially if tanks and pumps are required, removing the risk of floor ice and water damage makes the FX Prevent solution attractive. The European standard prEN 16750 gives more technical detail. If anyone is interested in learning more about this popular European method of fire prevention, please contact me on email@example.com or email Arina Duyvesteijn directly firstname.lastname@example.org.