With reports of barn fires in the news recently, the Iowa Pork Industry Center has gathered some resources about pit foaming to share with producers.
Manure pit foaming poses a serious fire and explosion hazard. Foam traps methane gas at extremely high concentrations. When foam is disturbed, methane can be rapidly released into the barn, creating the conditions for a flash fire if an ignition source is present.
Why Foam Is Dangerous
- Foaming manure can produce up to 3× more methane than non-foaming manure.
- Methane concentrations inside foam have been measured as high as 700,000 ppm (explosive limit ≈ 44,000 ppm).
- Disturbing foam during pumping or agitation can overwhelm ventilation systems.
SAFETY ALERT: Never disturb pit foam without adequate ventilation and removal of ignition sources. Flash fires can occur even in well-ventilated barns.
Graphic 1: Fire Triangle- Fuel (Methane), Oxygen (Barn Air), Spark…