Manure Pit Safety

Manure Pit

Denny Riethman, ANR Educator Mercer County

Wheat harvest will happen soon.  A common practice with livestock farmers is to apply manure nutrients following harvest of the wheat.  This increases the importance of reminding operators and applicators of following safety precautions when working around manure pits.  Planning ahead, developing Standard Operating Procedures (SOPs), ensuring everyone is trained, and good communication helps reduce the risk and keep everyone safe.

Manure pit gases are the biggest concern for health and safety around manure handling and storage pits. Hydrogen Sulfide, methane, carbon monoxide and ammonia are gasses of concern. Pit gases from any storage pit, whether closed, open, or under barn storage, can be toxic to both humans and livestock.  Hydrogen sulfide (H2S) gas is the biggest risk and is extremely dangerous and highly unpredictable.  Hydrogen Sulfide gas is released when agitating and pumping manure.  The gas is colorless, flammable and extremely hazardous with a rotten egg smell.  The gas is heavier than air, and will collect is low lying areas without good air movement.  If it is in the breathing area for people and animals, it can be immediately dangerous to life and health.

Manure applicators and individuals working around the barn and confined spaces are recommended to be equipped with H2S monitors or multi-gas detectors that will provide alerts when levels are increasing.  The alert system will give workers time to move away from higher gas concentration areas.  H2S gas concentration levels of 2 to 20 ppm will cause symptoms of nausea, headache, and dizziness.  H2S levels greater than 100 ppm will cause alerted breathing, collapse, and death.  Exposure to ammonia results in immediate burning sensation and redness in the eyes.  Methane and carbon monoxide are odorless and difficult to detect by smell.  The dangerous consequences from all of these gasses increases the importance of having multi-gas monitors in livestock buildings with manure pits below or around them.

It is important to understand the different types of personal protective equipment (PPE) available and the levels of protection they provide.  Having a self-contained breathing apparatus or supplied air respirator on hand is recommended.  Establishing a “Buddy System” in your operating procedures is important when working around manure pits in the event something happens, and someone collapses.  A safety belt or harness should be worn as a lifeline, should a worker need to enter a manure pit.  This allows a co-worker to stay in the peripheral area and keep a safe distance away and pull them to safety should the need arise.  The second person can also call for emergency help if needed.

Properly operating ventilation systems are very important for enclosed barns with manure pits below.  The ventilation system needs to exhaust the gases out of the barn especially while stirring and agitating the manure.  This is important for people working in the area, as well as the animals, to keep them from being fatally exposed to gases.  Think ahead to the process, make sure you are working with partners for maintenance.  If you need to enter a confined space, ventilate the area for a period of time before entering the area.  Follow the “Lock Out, Tag Out” procedure when doing maintenance or fixing equipment to ensure no one else accidently starts equipment you are working on or repairing.

Fencing and signage are important considerations around open manure pits to ensure that children, visitors, and animals are kept out.  Placing signage that indicates hazardous gases are present provides a visual warning and helps alert people to the risks in the area.

Producers and workers do not often see the susceptibility or severity of manure gas hazards.  Building awareness and communication for everyone in the operation is key.  Developing SOPs, training, and communication when working around manure pits is important.  Along with making safety a mindset and part of the thought process as you go through daily tasks, will reduce risks, and keep people and animals safe.

Denny Riethman, ANR Educator Mercer County, can be reached at 419-586-2179 or This column is provided by the OSU Extension Agricultural Safety and Health Team.