A Real Life Scenario

An example of a Permit Required confined space would be a wastewater treatment tank that is filled with a mixture of sulfuric acid and water. Many industrial wastewater tanks will also contain moving equipment such as an agitator. Agitators mix-up the contents of the tank and look like large propellers. Wastewater tank come in all sizes and can commonly be 25-30 feet deep.

As you can imagine, entry into the above described tank needs to be properly planned-out and a permit needs to be completed before entry into the tank. Let's start thinking about the steps we would take before we enter into the above described wastewater treatment tank.

1. Obtain confined space entry permit and fill out properly

2. Drain the tank

3. Flush the tank with water to remove any acid residue and then drain rinse water

4. Lockout/tagout all water and acid lines coming into and leaving the tank

5. Lockout/tagout the main disconnect controlling the agitator.

6. Test to ensure it is "off"

7. Use a blower motor to ventilate the space

8. Turn off blower motor and test air in the space with a confined space gas meter.

9. Turn blower motor back "on" when testing is complete.

Notice that all of the above items can be completed before you actually enter into the space. Once you complete the above items a qualified entry supervisor will confirm that acceptable entry conditions have been achieved and will sign the entry permit.

Once the permit is signed you will be allowed to proceed with entry into the tank. Other items that need to be considered when entering into the above described tank are: methods of entry and exit (ladders), fall protection ( may not be feasible), periodic gas checks, type of work you may be conducting in the space (welding will need additional permits), portable lighting, etc.