Ventilating Your Barn While Pumping Pits

Ventilating Your Barn While Pumping Pits

It’s time again that we start pumping manure out of our pits. With this comes the risk and responsibility of ventilating barns properly. Different barns require different strategies for ventilation. Understanding your scenario and proper planning can be all the difference in avoiding asphyxiation events or flash fires. Below are some guidelines to think about as you agitate and remove manure from your facility.

A few general guidelines to follow for improved safety and ventilation.

  • People should not be in the barn when the pit is being agitated and/or pumped
    • Think about adding caution signs on doors and/or putting lockout tags on exterior building doors
  • Turn off Heaters
  • Target a minimum of 30 CFM per pig for ventilation

Agitation Strategy

  • No agitation until manure is at least 1 ft below the support beams
  • Do not direct agitation nozzles towards walls or pillars
  • Stop bottom agitation nozzle when manure is less than 6” from the surface
  • Ensure agitation is subsurface (no rooster tailing)
  • No or minimal agitation when pigs are less than 50 lbs.
  • Tarp around pump to minimize pump out openings as fresh air inlets into the barn

Ventilating Tunnel Barns

  • Power actuated inlets
    • Warm Weather – 100%
    • Cold Weather – 85%
  • Tunnel Curtain – set curtain stop to allow at least a 6” opening, leave tunnel curtain in AUTO
  • Target 30 CFM’s per pig – This will usually take all remaining pit fans ON, and a 36” wall fan. You may have to do some math on what you have for fans to achieve at least 30 CFM/pig
  • During warm weather, run all pit fans on and no less than 2 tunnel fans
  • Continue ventilating at elevated levels for 1-2 hours after pumping

Natural Ventilated Barns

  • Power actuated Inlets: 100% OPEN
  • Run ALL exhaust fans ON
  • Stir Fans ON
    • Adjust so they are not downward directed, run them parallel to the flooring
  • Continue ventilating at elevated levels for 1-2 hours after pumping

Cold Weather

  • When wind is less than 5 mph leave curtains closed run ALL exhaust fans ON
  • When wind exceeds 5 mph Curtains open a minimum of 6” and ALL exhaust fans ON

Warm Weather

  • Open curtains and run ALL exhaust fans
  • Continue ventilating at elevated levels for 1-2 hours after pumping


As always, if you have questions on ventilating your barn while pumping pits, reach out to Nick Enfield or one of our Pipestone Grow Finish Field Supervisors.