Fire extinguishing and preventive and preparatory measures
Fires at silo sites are rare occurrences for most fire & rescue brigades and are different from conventional fires in many ways.
In many cases, the fires are caused by self-heating of the stored material resulting from different oxidation processes and biological activity that may cause pyrolysis, that is a smouldering fire in a highly oxygen limited environment.
A fire usually occurs deep inside the material and is therefore very difficult to detect and, in such cases, measuring certain gas concentrations (such as CO and CO2) in combination with temperature monitoring is usually the only opportunity to establish whether or not something serious is occurring.
Using this method to achieve early detection is a very important component of the prevention work for which the silo site owner is responsible, and by studying trends in measurements an early indication of abnormal conditions can often be gained.
A consequence of the relatively low fire frequency is that the fire brigades have little experience in dealing with such operations and that there is insufficient appropriate extinguishing equipment.
The fire development and the emergency response process are significantly different from conventional fire extinguishing.
In order for the emergency response to be as safe and effective as possible, it is important to consider the specific conditions of silo fires.
Swedish Civil Contingencies Agency (MSB)
Author: Henry Persson
Project manager: Ingvar Hansson, MSB
Editor English version: James Butler, MSB
Layout: Advant Produktionsbyrå AB
Publication number: MSB586 - July 2013