|Plant-Wide Hazards - Other OSHA Requirements and Programs
What is a confined space?
A confined space has limited or restricted means of entry or exit, is large enough for an employee to enter and perform assigned work, and is not designed for continuous occupancy by the employee.
Examples of confined spaces are:
What are the hazards that may be associated with confined spaces?
- Underground vaults,
- Storage bins,
- Pits and diked areas,
- Vessels, and
Because of the difficulties of entry and exit from confined spaces, employees who work in them may also face increased risk of exposure to serious injury from hazards such as entrapment, engulfment, and hazardous atmospheric conditions.
The atmosphere in a confined space can be hazardous due to the presence of chemicals that are either man-made, such as toxic fumes from welding operations, or naturally occurring, such as hydrogen sulfide or methane that can result from decomposing organic material. The oxygen level in a confined space may be reduced below that required for normal breathing. Gases that are heavier than air, such as carbon dioxide, may sink to the bottom of a confined space and reduce the level of oxygen breathed by a worker. Or chemical processes such as the formation of rust or bacterial action, as in the fermentation process, can use up the oxygen in a confined space.
In addition, the presence of flammable liquids or gases in a confined space presents a fire or explosion hazard
Work in confined spaces may keep employees closer to machinery components and power-driven equipment, such as augers, than they would be otherwise.
Heat, noise, vibration, and structural hazards such as scaffolding installed for maintenance, overhead structural members, or baffles also contribute to potentially unsafe conditions in confined spaces.
How does OSHA regulate confined spaces?
OSHA regulates confined spaces that have one or more of the following characteristics:
Where are "permit-required confined spaces" found in the poultry processing industry?
(1) contains or has the potential to contain a hazardous atmosphere;
(2) contains a material that has the potential for engulfing an entrant;
(3) has an internal configuration that might cause an entrant to be trapped or asphyxiated by inwardly converging walls or by a floor that slopes downward and tapers to a smaller cross section; and/or
(4) contains any other recognized serious safety or health hazards.
Such confined spaces are defined as "permit-required confined spaces" or "permit spaces" and are regulated by OSHA's standard
29 CFR 1910.146. (Overheads)
The following are examples of areas in poultry processing that need to be evaluated to see if they meet the definition of a "permit-required confined space":
What are an employer's responsibilities with regard to permit-required confined spaces? [Decision Flow Chart]
An actual case involved an employee who entered a tank that had contained chicken blood.
- Ice houses;
- Packing area: blast freezers chilled by carbon dioxide or nitrogen;
- Offal area: vats and pits;
- Wastewater handling/treatment area: settling tanks or vats, tanks of sulfuric acid, hydroxides, or other chemicals; and
- Gas storage areas: large ammonia, carbon dioxide, nitrogen, or chlorine tanks.
OSHA's standard requires employers to determine whether there are any permit-required confined spaces in their facility.
If there are, employees must be informed of them and of the dangers posed by them.
If employees are not to enter and work in permit spaces, the employer must take effective steps to prevent employee entry.
If employees are to enter permit spaces, the employer must develop a written permit space program, which will (Overheads):
- Identify and evaluate permit space hazards before allowing employee entry;
- Test conditions in the permit space before entry operations and monitor the space during entry;
- Perform, in the following sequence, appropriate testing for atmospheric hazards: oxygen, combustible gases or vapors, and toxic gases or vapors;
- Implement necessary measures to prevent unauthorized entry;
- Establish and implement the means, procedures and practices - such as specifying acceptable entry conditions, isolating the permit space, providing barriers, verifying acceptable entry conditions, purging, making inert, flushing, or ventilating the permit space - to eliminate or control hazards necessary for safe permit-space entry operations;
- Identify employee job duties;
- Provide, maintain, and require, at no cost to the employee, the use of personal protective equipment and any other equipment necessary for safe entry (e.g., testing, monitoring, ventilating, communicating, and lighting equipment; barriers, shields, and ladders);
- Ensure that at least one attendant is stationed outside the permit space for the duration of entry operations;
- Coordinate entry operations when employees of more than one employer are to be working in the permit space;
- Implement appropriate procedures for summoning rescue and emergency services;
- Establish, in writing, and implement a system for the preparation, issuance, use, and cancellation of entry permits;
- Review established entry operations annually and revise the permit-space entry program as necessary; and
- When an attendant is required to monitor multiple spaces, implement the procedures to be followed during an emergency in one or more of the permit spaces being monitored.
Before initial work assignments, employees must be trained in the understanding, knowledge, and skills necessary for the safe performance of their duties.
Specific OSHA Requirements
Additional training is required when:
Rescue team members must have also been trained in:
- Job duties change,
- There is a change in the permit-space program or the permit space operation presents a new hazard, and
- When an employee's job performance shows deficiencies.
The standard also requires coordination with contractors. (Overheads)
- Proper use of personal protective equipment and rescue equipment,
- Performance of assigned rescue duties,
- First aid and cardiopulmonary resuscitation (CPR), and
- Yearly practice rescue exercises.
The user of this adviser is encouraged to consult the standard and other documents referenced below for additional information.
29 CFR 1910
Occupational safety and health standards
NOTE: Employers in states with state-run safety and health plans should check with their
state agency. Their state may be in enforcing standards that, while "as effective as federal standards," may not be identical to the federal requirements.
Confined Spaces. OSHA Publication 3138,
(2004). Also available as a 486 KB PDF,
Permit-required confined spaces
OSHA Publication 2209-02R, (2005). Also
available as a 260 KB PDF,
Application of the Permit-Required Confined
Spaces (PRCS) Standards, 29 CFR 1910.146. OSHA Directive
CPL 02-00-100 [CPL 2.100], (1995, May 5).
Contact the OSHA Directorate of Technical Support and Emergency Management at 202-693-2300
for assistance accessing PDF materials.