Confined Space Entry Toolbox Talk

Every so often we may be asked to enter a confined space. Did you know there are special rules that must be followed in order to save your life? Entering manholes, vaults, pits, storage tanks, boilers and other types of confined spaces presents special hazards.

Before you enter any confined space, you should first have a permit, which means you must plan your work. Survey the confined space to assess the hazards and make certain all lines to and from the vessel are effectively blinded or disconnected by:

• Place blinds in the lines as near to the vessel as possible.
• Disengage all lines to the vessel equipped with unions and plug the lines.
• Use full face gaskets with blind flanges in acid areas only. Use a gasket cutter, not a knife, to cut the gasket in order to eliminate holes in the middle of the gasket.

Lock out all electrical equipment including pumps, agitators, fans, and the heat trace and level indicator. Make all toxic or flammable equipment gas-free by:

• Purge equipment or tanks with steam or flush them with water, air or inert gas and vent them to dissipate hydrocarbons or other chemicals.
• Water-wash the vessel to cool it for entry if necessary.
• Remove the top and bottom entryway on the vessel where it is practical.
• Use air movers where practical and as long as they are needed to move air throughout the confined space, thus eliminating dead spaces.

Maintain a breathable air supply with the use of a purifying respirator, air-line fed respirator, a self-contained air supply or constant exchange of air in the confined space, whichever is required.

Properly identify and tag valves that are not to be operated and remove valve handles where possible. Periodically test the atmosphere to ensure that it does not change. Oxygen must be 19 percent as a minimum. Any reading on an explosive meter requires finding the explosive or flammable source. Testing of toxicity is based on industrial hygiene sampling of the last contents in the tank.

Other factors to consider in planning your work include:

• Have a welding and burning permit before attempting such work in the vessel.
• Use only low-voltage lights in metal tanks or wet floor areas.
• Watch for flammable or toxic vapor sources in nearby areas.
• Post warning signs around the vessel stating vessel entry in progress.
• Collect all safety equipment that is necessary to complete the job.
• Have detailed instructions on how to do the job.
• Provide a means or procedure for rescue.
• Use the buddy system and make sure that the individual NEVER leaves the opening once you have entered the confined space. This person must always be able to see or talk to you.

Once you have reviewed the checklist, you can prepare to enter the vessel. Remember to wear your safety equipment, including a body harness and safety line, a respirator and protective clothing as needed.

Make sure standby persons are also equipped with the same equipment as you are in case of an emergency.

Review the work to be done once again, as well as any last minute instructions on what to do in case of an emergency. Enter the vessel and perform the job.

You’ve planned your work, so now work your plan. These are just some of the important items of confined space entry, and because every situation is different, these items do not always apply. Therefore, only authorized and competent persons should be allowed to enter a confined space.