A 14'' x 10'' 4 mil Pressure-Sensitive Vinyl "DANGER" sign warning of confined space; Entry by permit only. Entry by trained personnel only. Entering this confined space is NOT a routine operation.
DO IT SAFELY!
Permission
Get a written permit from your certified supervisor
Preparation
Lock out power feeds
Shut off heating system if needed
Drain if needed
Vent vapors if needed
Post ''WORKER IN CONFINED SPACE'' signs
Isolation
Disconnect fill and drain lines if needed
Ventilation
Force air to bottom of Confined Space and vent to outside
Check air inside Confined Space
At least 19.5% Oxygen
No more than 23.5% Oxygen
Check for explosive limit 0% LEL
Check toxic vapors if needed
Protect yourself
Wear gloves and other safety clothing
Put on harness and lifeline
Continuously monitor the air
Rescue backup
Observer with auxiliary air supply standing by before you enter and until you exit, SAFELY