How to manage confined spaces in your workplace ~ HSE Materials

Many workplaces contain equipment and facilities considered to be "confined" because their configurations hamper the activities of employees who must enter, work in, or exit from them. In many instances, employees who work in confined spaces also face an increased risk of exposure to serious physical injury from hazards such as entrapment, engulfment, and hazardous atmospheric conditions. Confinement itself may pose entrapment hazards and work in confined spaces may keep employees closer to hazards such as machinery components than they would be otherwise. For example, confinement, limited access, and restricted airflow can result in hazardous conditions that would not normally arise in an open workplace.

What is a confined space?

A confined space is a space that: (i) is large enough and configured so an employee can enter and perform assigned work; (ii) has limited or restricted means for entry or exit, and (iii) is not designed for continuous employee occupancy.

Confined spaces as per OSHA.

Examples of confined spaces

You can consider as a confined space all types of equipment you find in your workplace such as:

Tanks;

Manholes;

Boilers;

Furnaces;

Sewers;

Silos,

Hoppers;

Vaults;

Pipes;

Tranches;

Tunnels;

Ducts;

Bins;

Pits;

etc...

Permit-Required

Some confined spaces require a permit to enter if it has one or more of the following conditions:

It contains or has the potential to contain a hazardous atmosphere.
Contains a material with the potential to engulf someone who enters the space.
It has an internal configuration that might cause an entrant to be trapped or asphyxiated.
It contains any other recognized serious safety or health hazards.

The false appearance of confined space being safe

A confined space often appears to be harmless; no danger signs are apparent and the space may have been entered on prior occasions without incident. However, a worker cannot assume conditions have not changed and the area is safe for entry each time.

Below is a list of other hazards workers may encounter in a confined space:

Space configurations such as small openings, can trap an entrant, restrict easy entry and exit, or impede rescue.
Atmospheric hazards such as gasoline tank vapors, combined with limited ventilation. . Such conditions can cause asphyxiation or explosion. Oxygen levels may be hazardous and cause asphyxiation (less than 19.5%) or fire (over 23.5%).
Physical hazards, such as unstable grain contained in silos, can engulf a worker.
All other serious hazards, such as electrical equipment, moving machinery, falling objects, and wet or slippery surfaces

Below is a list of potential hazards to be aware of when working in a confined space

No ventilation (pits and vaults seldom opened).
Leaking chlorine gas (which is heavier than air) can accumulate in low-lying areas.
Oxygen depletion; which can be caused by:

Rotting vegetation and decaying dead animals.

Corroding or rusting machinery.

You must test the space's internal atmosphere for oxygen content, flammable gases and vapors, and the potential for toxic air contaminants before any worker enters it. You must also provide continuous ventilation and verify that the required measurements are performed before entry.

Confined Space Entry Team

Team members working in confined spaces must have the knowledge, skills, and abilities (KSAs) to safely enter and work in the confined space. (See this article related to Safety Training).

The entrant(s) - the person or persons who will enter and perform work in the confined space;
The attendant - the person who remains at the confined space entry and monitors entrant status;
The entry supervisor - is responsible for the permit and all confined space activities, and
Rescue personnel - if assigned by the employer, they are on duty and ready to perform rescue activities.

The Employer (or his delegate) is responsible for the following measures:

Identify and assign entry team members;
Make sure hands-on training of entry team members is completed before the first entry;
Make sure medical evaluations, fit testing, and respirator training are conducted; and
Ensure entry and rescue teams have adequate personal protective and rescue equipment.

Confined Space Entry Supervisor Responsibilities

The Confined Space Entry Supervisor holds a key position with important responsibilities below:

Ensure requirements for entry have been completed before access is authorized;
Authorize access and oversee entry operations;
Ensure confined space monitoring is performed by personnel qualified and trained in confined space entry procedures;
Ensure that the rescue team has simulated rescue in a confined space within the past twelve months;
Know the hazards that may be faced during entry, including the mode, signs or symptoms, and consequences of exposure;
Fill out a permit when it is required;
Determine the entry requirements and that conditions are acceptable for entry;
Notify all involved employees of the permit requirements;
Post the permit in a location near the job;
Renew the permit or have it reissued as needed (a new permit is required every shift);
Ensure the attendant knows how to communicate with the entrants and how to obtain assistance;
Ensure measures are in place to keep unauthorized personnel clear of the area
Post any required barriers and signs
Remain alert to changing conditions that might affect the conditions of the permits
Ensure periodic atmospheric monitoring is done according to permit requirements
Ensure the permit is canceled when the work is done
Ensure the confined space is safely closed and all workers are cleared from the area
Ensure necessary information on chemical hazards is kept at the work site for the employees or rescue team
Ensure a rescue team is available and instructed in their rescue duties

Confined Space Entrant Responsibilities

Read and observe the entry permit requirements

Stay alert to the hazards that could be encountered in a confined space

Use the protective equipment required by the permit

Must immediately exit the confined space when:

Ordered to do so by the attendant

Automatic alarms sound

hey perceive they are in danger

They notice physiological stresses or changes in themselves or co-workers

Confined Space Attendant Responsibilities

The Attendant should be stationed outside the workspace and should:

Be knowledgeable of, and be able to recognize potential confined space hazards;

Maintain a sign-in/sign-out log with a count of all persons in the confined space and ensure all entrants sign-in/sign-out;

Maintain effective and continuous communication with personnel during confined space entry, work, and exit;

Order personnel to evacuate the confined space if he:

Observes a condition that is not allowed on the entry permit;

Notices the entrants acting strangely, possibly as a result of exposure to hazardous substances;

Notices a situation outside the confined space which could endanger personnel;

Detects within the confined space a hazard that has not been previously recognized or taken into consideration;

Must leave his/her work station; or

Must focus attention on the rescue of personnel in some other confined space that he/she is monitoring

Immediately summon the Rescue Team if crew rescue becomes necessary

Confined Space Rescue Team Responsibilities

The Rescue Team members should meet the following requirements:

Complete a training drill using mannequins or personnel in a simulation of the confined space before the issuance of an entry permit for any confined space and at least annually after that.

Respond immediately to rescue calls from the Attendant or any other person recognizing a need for rescue from the confined space.

In addition to emergency response training, receive the same training as that required of the authorized entrants.

At least one member of the rescue team must hold current certification in first-aid and CPR.

Confined Space Rescues

Rescues can be performed by any employee or a professional rescuer so long as they have been fully trained and qualified to act as rescuers. Qualifications include knowledge of and experience working with all hazards associated with rescue and confined space entry operations. Ensure that an attendant is present immediately outside the space if the person in the space needs assistance and ensure that an emergency retrieval or rescue method is available. Ensure that structures are sound (safe) from collapse prior to entering confined spaces. Use proper personal protective equipment, which will be determined by the hazards encountered in the confined space. Never enter a confined space to attempt an emergency rescue unless you have been trained in safe confined space entry and rescue procedures and have the proper tools and personal protective equipment

Remember:

EXIT THE CONFINED SPACE IMMEDIATELY IF AN UNSAFE CONDITION DEVELOPS!

Fatalities can occur when the rescuers:

Are overcome by their emotions

Take unnecessary chances

Do not know the hazards involved

Do not have a plan of action

Lack of confined space rescue training

Rescue Equipment

The importance of having the right rescue equipment on hand cannot be stressed enough. Rescue equipment may include:

Full body harness with a retrieval line attached;

Wristlets (may be used in rescue when it can be shown that they are the safest and most effective means of rescue);

Hand-cranked mechanical winch and tripod;

Ladder;

Explosion-proof lighting;

Stretcher;

Head protection;

First Aid equipment.

Respiratory Protection

If a hazardous atmosphere exists in the confined space, such as toxic gases, employees may use an appropriate air-purifying respirator. However, if the confined space lack oxygen, an air-purifying respirator will do no good, there is no supply of oxygen to breath breathe in the first place. In this situation, an entrant would need to wear an air-supplying respirator which will supply breathable air and will protect the entrant from breathing in hazardous air from the confined space atmosphere.

Confined Space Training Requirements

Employers must provide training to all entrants so that they gain adequate knowledge, skills, and abilities (KSAs) to safely perform their duties in confined spaces. Rescue team members also require training in CPR and first aid. Entrant training or retraining should occur:

before the worker starts work;

before there is a change in assigned duties;

whenever there is a change in permit space operations that presents a hazard about which a worker has not previously been trained;

whenever the supervisor finds changes in the permit space entry procedures; or

when an entrant displays a lack of knowledge, skills, or abilities (KSAs).

(See this article related to Safety Training).

General Training

All (i) workers who will enter confined spaces must be trained in entry procedures and (ii) personnel responsible for supervising, planning, entering, or participating in confined space entry and rescue must be trained in their duties before any confined space entry.

Training should include:

Explanation of the general hazards associated with confined spaces and the hazards related to the operations to be done inside the confined spaces;

Reason for, proper use, and limitations of PPE and other safety equipment required for entry into confined spaces;

Explanation of permits and other procedural requirements for conducting a confined space entry;

A clear understanding of what conditions would prohibit entry;

How to respond to emergencies;

Duties and responsibilities as a member of the confined space entry team;

Description of how to recognize (i) symptoms of overexposure to probable air contaminants in themselves and co-workers, and (ii) methods for alerting Attendants.

Procedures for summoning rescue or other emergency services.

Proper use of equipment for communicating with entry and emergency/rescue personnel.

Refresher training should maintain worker competence in entry procedures and precautions. If workers did not enter a confined space at least annually to perform work for an extended period of time, they should be provided an opportunity to practice entry procedures.