To mitigate potential hazards and ensure regulatory compliance in confined spaces, a comprehensive approach is required. This includes hazard assessment, control programs, and adherence to established safety procedures.

A confined space hazard assessment and control program should be implemented, specific to the work being conducted in each confined space. [3]

Key components of a confined space program include:

• Description of roles and responsibilities.
• Identification and assessment of potential hazards.
• Atmospheric testing and monitoring procedures.
• A plan to eliminate or control all identified hazards.
• Written work procedures.
• Training programs for all workers entering confined spaces.
• Establishment of an entry permit system.

Before entering any confined space, a trained and experienced person should identify and evaluate all existing and potential hazards within the confined space, evaluating activities both inside and outside the confined space. [5]

Air quality testing should be conducted from outside the confined space before entry, ensuring air is tested throughout the space. Continuous monitoring should be considered where atmospheric conditions may change. [5]

The air quality testing should confirm:

• Safe oxygen content.
• Absence of hazardous atmosphere (toxic gases, flammable atmosphere).
• Proper operation of ventilation equipment.

If potential flammable atmosphere hazards are identified, the air in the confined space should be cleaned or purged, ventilated, and tested again before entry is allowed. [1]

All potentially hazardous energy sources must be de-energized (or isolated) and locked out prior to entry to prevent unintentional activation. [1]

Other safety precautions include:

• Removing liquids or free-flowing solids to eliminate drowning or suffocation risks.
• Physically disconnecting or using isolation blanks on all pipes.
• Using double blocking valves with an open vent or bleed valve when isolating pipelines.
• Ensuring a barrier is present to prevent liquids or solids from entering the space.

Natural ventilation is typically insufficient; mechanical ventilation is usually necessary to maintain air quality. If mechanical ventilation is used, a warning system should be in place to notify workers of ventilation equipment failure. [2]

An entry permit system should be in place, documenting hazard and risk assessments for each confined space entry. [8]

The entry permit should include:

• The length of time the permit is valid for.
• The names of authorized workers and attendants.
• The name of the supervisor responsible for the work.
• The location and description of the confined space.
• Details of atmospheric testing.
• Hazard control measures.
• Means of communication.
• Emergency plan details.
• Signatures of workers who did the confined space air testing and the supervisor.

At least one attendant should be posted outside the confined space to continuously monitor the workers inside and maintain constant two-way communication. [6] [7]

Emergency response procedures should be detailed in the confined space hazard assessment and control program. Rescue personnel qualified in confined space rescue procedures should be available immediately nearby. [7]

Appropriate training is crucial for all workers involved in confined spaces, including entrants, attendants, and rescue personnel. [4]

Training should cover:

• Recognition and identification of potential hazards.
• Evaluation and control procedures for identified hazards.
• Set-up, use, and limitations of all equipment.
• Set-up, use, and limitations of personal protective equipment.
• Communication and retrieval systems.
• Safe work procedures.
• Emergency procedures.
• First aid and CPR.
• Specific work to be done.
• Working in a manner that will not endanger lives.