Confined Space Entry, Part 2

Communication systems do not need to be elaborate, but they must be effective.

THE attendant is the last individual external to the confined space who can monitor working conditions that will ensure the safety of the workers inside the work space. Attention to specific details outlined on the work permit, the ability to adequately oversee "permitted operations," and the authority to "stop work" when rules are violated are the critical elements of the responsibility.

Attendants must remain at the work site whenever workers are inside the work space. Nothing is more unforgivable than an attendant who is absent when a worker is trapped. There is no excuse. Attendants must make certain they can perform all required duties before accepting the responsibility.

Can an attendant have responsibility for several confined work spaces at the same time? Can different work permits be policed by a single attendant? How many workers inside confined spaces can be safely monitored at one time? Can attendants perform emergency rescue operations?

Attendants are people, and they have limitations. When proper training is provided and responsibilities are clearly understood, reasonable assignments will result. Workers inside confined spaces need reliable "guardian angels" whom they can depend on to save their lives.

Attendant duties can be divided into several areas (see Table 1, above). In the table, the green background indicates it is safe to proceed with work; yellow indicates caution; and red indicates danger or stop work until specific safety requirements are met.

Attendants must:

1. Make certain that the entry permit is properly completed with potential hazards and safeguards identified, the names of all "confined space team members" listed, and the rescue team on stand-by status. The physical effects of adverse exposure to possible hazards must be understood, the ability of each team member to perform assigned duties must be carefully reviewed.

Residual energy from equipment not properly shut down can cause entrapment. Work environments that can become oxygen-enriched are explosive. Rescue team members weighing 300 pounds cannot fit into limited-opening confined spaces. Work should not commence until all safety issues are discussed and satisfactorily resolved.

2. Make certain that all changes to a work permit (manpower, hazards, procedures, etc.) are properly reviewed with, and authorized by, the entry supervisor before the changes are completed. The attendant must always have the right to challenge the feasibility and completeness of any change. Conditions that warrant immediate evacuation of the work space must be identified in advance (i.e., before any work begins). Authority to order a work stoppage must be given to the attendant.

If the attendant is unable to perform assigned duties at any time during the life of the permit or if several team members become unavailable (i.e., rescue team is "out to lunch"), an immediate evacuation of the work space must result. Immediate evacuation is required when the inability to perform or the absence of required manpower occurs.


A miscount could cause an unidentified entrant to be overlooked during rescue operations.

3. Make certain that hazards inside and outside the work space do not and are not causing additional risk to workers. Environmental conditions outside the work space must be periodically monitored and collected data must be recorded and reviewed to make sure safe exposure levels are not exceeded. External conditions must not restrict safe egress from the work space or create new safety concerns.

Material and equipment flow into and from the work space also must be monitored to make certain that unauthorized work is not being done. New materials, particularly solvents or chemicals, may not be compatible with those already inside the work space. Co-mingling can create unanticipated hazards that cause serious health risks.

4. Make certain that "stand alone" rescue equipment that is operational is located at the work site and available for emergency use. Rescue air lines and masks must be provided for all rescuers and occupants inside the confined space.

Emergency rescue equipment should never be shared. Air bottles must have a sufficient supply of breathable air (a portable rescue cart and a cascade air system generally are provided) to ensure completion of the required rescues. Other types of portable units are also available. Use of plant supplied air is illegal when emergency rescue is necessary.

5. Make certain that protective equipment provided for use inside the work space is adequate for the hazard(s) involved. Monitoring results indicate oxygen, flammability, and toxicity levels inside the work space. As hazards increase, it may be necessary to change protective equipment. Use of respiratory equipment with plant supplied air is acceptable, provided the air supply system has condensate and particulate filters and an audible carbon monoxide alarm that sounds when CO levels in the breathable air approach 20 percent. If the alarm sounds, the attendant must order an immediate evacuation of the work space.

Safe exposure levels are also established for all solvents and chemicals. The attendant must be aware of the exposure levels for the materials being used inside the work space. When monitoring results indicate that these levels are being exceeded, an IDLH (immediately dangerous to life and health) environment exists, and an evacuation should be considered. The work space should then be ventilated with forced air or other means, if possible, to reduce exposure levels before work resumes.

Work should never resume, and rescue operations should not be conducted, when the environment is oxygen enriched.


There is no harm in ordering an unnecessary work space evacuation except downtime and a little lost production.

6. Make certain that effective communications are maintained with all occupants inside the work space. The occupant must be able to "call for help" without being contacted by the attendant. Conversely, the attendant must know when the occupant is being adversely affected by exposures inside the work space. Symptoms and side effects of the materials being used must be reviewed before work begins. All workers must know when their ability to perform work is being impeded.

Communication systems do not need to be elaborate, but they must be effective. Tugging on a lifeline or tapping on a surface can be sufficient. The objective must be to ensure the safety of the occupant.

Do's and Don'ts for the Attendant
Never leave your work station
unless relieved by another authorized attendant. The work permit and work status must be reviewed before transfer of responsibility.

Always know who is in the work space. A miscount could cause an unidentified entrant to be overlooked during rescue operations.

Never enter the confined space to rescue anyone without proper entry training, and not until relieved by another authorized attendant. Always "look before you leap," or you may jeopardize the safety of all entrants and become the victim of your own carelessness.

There is no harm in ordering an unnecessary work space evacuation except downtime and a little lost production. And there is no harm in expressing concern about your ability to perform all assigned attendant duties. Confined space work is serious business with serious consequences when mistakes occur. It is better to be safe than sorry.

This article appeared in the March 2006 issue of Occupational Health & Safety.


References
1. American National Standards Institute, Safety Requirements For Working In Tanks and Other Confined Spaces, Z117.1.

2. Bender, Thomas R., et al., Worker Deaths in Confined Spaces: A Summary of Surveillance Findings and Investigative Case Reports, U.S. Department of Health and Human Services, Publication No. 94-103.

3. National Institute for Occupational Safety and Health, Criteria for a Recommended Standard: Working in Confined Spaces (Publication No. 80-106).

4. National Institute for Occupational Safety and Health, A Guide to Safety in Confined Spaces (Publication No. 87-113).

5. National Safety Council, Confined Space Entry Control System for R&D Operations, Data Sheet No. 704.

6. U.S. Department of Labor, Code of Federal Regulations, Part 1910.146, Permit Required Confined Spaces.

This article originally appeared in the March 2006 issue of Occupational Health & Safety.

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