by Cheryl A. Skjolass
Injuries and fatalities occur in confined space manure storages that are enclosed, such as beneath animal quarters; or below-ground reception and pump out pits; and in non-enclosed earthen, synthetic, or concrete-lined manure storages. Non-enclosed manure storages are open to the atmosphere but may meet the definition of a confined space in terms of occupational safety and health based on storage design and employee exposure to hazards.
In the case of non-enclosed manure storage, hazards may include:
- A thick liquid and floating crust that make swimming, buoyancy, or even moving around very difficult.
- Steep and slippery slopes that can make getting out of manure storages difficult or impossible.
- An acceleration of hazardous gases (primarily methane, hydrogen sulfide, carbon dioxide, and ammonia) released from manure due to movement, agitation, removal, or addition of manure to storage.
- Localized layers of hazardous gases existing above manure surfaces, especially on hot, humid days with little to no breeze.
- Not having sufficient oxygen to breathe if a person is ‘treading’ in manure because of inability to get out.
- Not being able to see into depths of manure like you can with clear water.
- A slow response time for adequate emergency actions because of site isolation and remoteness.
- Potentially hazardous equipment in and around the manure storage.
Safety guidelines to follow:
- Make sure everyone near manure storage structures understands the hazards that exist, including symptoms and effects that the various manure gases have on their health.
- Explosive gas may settle in pockets near where agitation or pumping is occurring.
No smoking, open flames, or sparks should be allowed.
- Make sure the non-enclosed manure storage has a fence installed around the perimeter and access gates are locked to keep unauthorized personnel from entering the area.
- Post warning signs including manure drowning hazard signs and “Danger Manure Storage” or “Danger Keep Out,” or “Danger Keep Away,” on all sides of non-enclosed manure storage. If possible, these signs should be located by gates.
- Keep bystanders and non-essential workers away from non-enclosed manure storage during or other accessible areas during when pump out operations are in progress.
- Wear a safety harness with life-line attached to a safely located solid object or anchor at any time you enter the fenced-in area of non-enclosed manure storage. If retrieval is needed, this equipment will improve the possibility of a successful rescue.
- Never work alone. The second person’s role is to summon help in an emergency and assist with rescue without entering the manure storage.
- Move slowly around unenclosed manure storages as the ground can sometimes be uneven and may cause a person to trip or stumble.
- Understand equipment being used and have emergency shut-down procedures prepared.
- If equipment malfunctions or maintenance is required during agitating or pumping of the manure, shut all equipment off and remove it from the manure storage before servicing or repairing.
- If you feel unsure or uncomfortable with what you are getting ready to do near the manure storage; wait a moment and reconsider the action, contact a supervisor or farm manager, and review the situation before proceeding.
- Be prepared to call 911 in case of an emergency. Being prepared includes providing specific directions to the site of the emergency, accurately describing the incident, and number of victims.
Source: UW- Extension Fond du Lac County