To ensure hot tapping procedures are safe, secure and economically viable, its important to do a preliminary safety check. Along with a activity worklow, this 7 step hot tapping safety checklist can aide you in your attempts to hot tap.
Ensure that the colleague in charge of the process is committed to being present during the process. Them, and other colleagues, should be trained and familiar with the process, welding procedures and the use and location of applicable equipment.
A plan should have also been prepared to monitor and control process variables within their required limit.
The area where the connection is to be made must be identified and physically marked. The metal thickness should also have been verified at this point, taking into consideration measurements that meet the current metal condition.
Any imperfections that may prevent a proper weld should have been evaluated and approved by a trained member of the team.
Hazards and contaminants
All necessary testing for flammable vapors and hazardous air contaminants should have been conducted at this stage. At the same time, personal protective equipment (PPE) should be made available to personnel, including fire retardant clothing.
A dedicated fire watch team has to be established and equipped with suitable fire extinguisher or pressurised fire hose. This person(s) should understand all their duties and be able to communicate strongly with all members of the team.
Permits and barriers
All hot tapping permits, including confined space entry (if required), need to be obtained and approved. Signs and barriers should be provided to isolate the area from any unauthorised people.
Just like any process in the world, a contingency plan should be in place. For hot tapping, and emergency action plan should also be drawn up.
This should include a communication plan to all relevant parties involved, firewatch has been familiarised with equipment on site, and all technical specifications such as temperature, pressure and process material are recorded.
All safety procedures should also be in place to prepare for any emergency.
After all these preparations have been put in place, the trained personnel should inspect the weld, hot tapping machine itself and both elements together before pushing the button on the process.
Once work has been started it should proceed without interruption until the hot tap has been completed and the valved closed. For ultimate safety, the American Petroleum Insititute recommend that the fire watch team should remain at the site for 30 minutes after the process has been completed.
If you're in any doubt about the machine itself, refer back to the product manual at any stage.
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