Manure Pit Standards and Regulations

There are two national consensus standards and one federal government regulation that are relevant to the design, construction and operation of confined space manure storages.
Manure Pit Standards and Regulations - Articles

Updated: September 8, 2017

Manure Pit Standards and Regulations

The primary purpose of the ANSI/ASABE S607 standard is to reduce risk from asphyxiation, poisoning, and explosions when entering confined space manure storages by specifying ventilation requirements and parameters. The primary purpose of the ASABE EP 470 engineering practice is to identify existing known practices that help to minimize the hazards of manure gases to livestock and humans. The link to the federal regulation, OSHA, is to help producers understand how OSHA's general duty clause and regulation on confined spaces may apply to their operation. Click on each link below for more details.

ANSI/ASABE S607

Approved November 2010 as an American National Standard - Ventilating Manure Storages to Reduce Entry Risk.

The primary purpose of this standard is to reduce risk from asphyxiation, poisoning, and explosions when entering confined space manure storages by specifying the positive pressure, forced ventilation requirements, including ventilation system layout, air exchange rates, and minimum ventilation times, for evacuation of contaminant gases from, and replenishment of oxygen into, empty or nearly empty covered or partially covered confined-space, on-farm, manure storages, reception tanks, agitation tanks and other similar containers that hold/contain manure prior to entry. This standard is to be used in conjunction with the appropriate confined space entry considerations defined in ASAE EP470, JAN 1992, R2005, Manure Storage Safety.

This Standard specifies the forced-ventilation times required to evacuate contaminant gases (H2S, CH4, and CO2) from on-farm, confined-space, manure storages with either solid, totally slotted or partially slotted covers to concentrations below American Conference of Governmental Industrial Hygienists (ACGIH) recommended 8-hr. Threshold Limit Values (TLV's).

The full-text of this standard can be ordered from ASABE for $55. Call 269-932-7024 or email martin@asabe.org. ASABE members and non-members associated with institutions or companies who have signed a license with ASABE can access at no charge from the online Technical Library.

ASABE EP470

JAN 1992 (R2005) - Manure Storage Safety

The purpose of this Engineering Practice is to set forth existing known practices on manure storages that help (1) minimize the hazards of manure gases to livestock and humans, and (2) minimize the potential for drownings at manure storage sites. This Engineering Practice does not include the design loads or structural specifications for manure storages (see ASAE Engineering Practice EP393, Manure Storage). This Engineering Practice contains information on safety equipment, management suggestions on safety, and the manure gases hydrogen sulfide, methane, ammonia, and carbon dioxide. Also given is a listing of the maximum safe gas concentrations, related standards and practices, and pertinent references.

The full-text of this standard can be ordered from ASABE for $55. Call 269-932-7024 or email martin@asabe.org. ASABE members and non-members associated with institutions or companies who have signed a license with ASABE can access at no charge from the online Technical Library.

OSHA

Relevant OSHA Standards or Standard Sections

The Occupational Safety and Health Act (OSHA) is the primary regulation that governs occupational safety and health in the U.S. OSHA has a standard that governs entry into confined spaces (Standard 1910.146, see below for a direct link) but production agriculture has been specifically exempted from this standard. One may think there is no reason for a farmer to be concerned about their confined space manure storage and the OSHA regulation, but this is not completely accurate. If a farm operator employs 11 or more non-family workers and is inspected for any reason, OSHA can use its "general duty clause" to cite the employer for violation of easily recognized best safety practices. Section 5 of the OSHA standard identifies specific duties for employers and employees The OSHA general duty clause says, in part, that each employer shall furnish to each of his employees employment and a place of employment which are free from recognized hazards that are causing or are likely to cause death or serious physical harm to his employees. See below for a direct link to the complete Duties section.

The hazards of manure storages are well-documented. Allowing a hired worker to enter a manure pit without an adequate supply of contaminant-free air, without a safety harness with a lifeline attached to a rescue lifting device, or without using atmospheric testing devices, violates best safety practices for entering manure pits.

State OSHA

Several states have their own state Occupational Safety and Health regulation. One provision in the federal OSHA Act is that if a state adopts a state OSHA plan it has to be at as strict or stricter than the federal regulation. This means that in states with their own OSHA plan, farm operations may not have the same exemptions from standards or enforcement of standards as exists in states where only federal OSHA is in effect. Farmers should know if their state has a state OSHA plan and how those regulations may differ from federal OSHA regulations.

Check to see if your state has a state approved OSHA plan.

Instructors

Agricultural Safety and Health

More by Dennis Murphy, Ph.D.