OSHA (Occupational Safety and Health Administration-USA) defines a Confined Space, as one that has limited or restricted means of entry or exit, is large enough for employees to enter and perform their work, and is not designed for continuous occupancy. Types of facilities which are designated as confined spaces are Manholes; Sewer lines or tunnels; Storage tanks; Silos; underground utility vaults and storage; Boilers; Pipelines; Pits; Wells etc.
Some of the general categories of hazards, which may be encountered in permit required confined space:
• Atmospheric hazards.
• Engulfment hazard.
• Mechanical and Electrical hazards.
• General Safety (means of access / egress, trips, slips falls, hot, cold, biological hazards etc.)
Safely working in Confined Spaces:
• Safety program shall be established for working in confined spaces.
• All personnel working in confined shall be medically fit, competent and in possession of required PPE.
• Before anyone can enter the permit required confined space (PRCS) to work, there must be a written entry permit.
• Measuring and monitoring for atmospheric hazards is one of the important things to remember when doing confined space work.
Oxygen: According to the OSHA standard, 19.5 % is the minimum and 23.5 % is the maximum range for oxygen in PRCS.
Combustibles: Measure the percent of LEL (Lower Explosive Limit) and according to the OSHA standard, the acceptable level for any combustible is at or below 10% of its LEL.
Toxic: Measure the concentration of toxic substances which might be available and compare same with TLV (Threshold Limit Value). According to the OSHA standard, TLV for Hydrogen Sulphide is 10 ppm (ACGIH recommendation 1 ppm) and for Carbon Monoxide (CO) it is 50 ppm
• One employee (Attendant) will remain outside of the space to be available in case of an emergency. This individual must be in direct communication with the other workers in the confined space, as well as have the capability to reach emergency response personnel.
• Emergency and Rescue Plan Procedures shall be established during confined space work.
In summary, we can say that confined spaces are significantly more hazardous than normal workplaces. Confined space activities are considered 150 times more hazardous than office work. The resulting injuries are potentially fatal. A seemingly insignificant error or oversight while working in a confined space can result in a tragic accident. Hence proper management and controls are required before undertaking such activity.
TÜV Middle East provides Confined Space training courses and it is available in the United Arab Emirates (UAE), Kuwait, Saudi Arabia, Bahrain and Oman.
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