1. Follow Industry’s & Company’s Best Safety Practices. Safety is always our FIRST PRIORITY. Follow job Hazard Analysis prior to performing any work and ensure you have the proper training.
2. Do not design any relief valves for equipment & piping unless it is required by codes and DTC or client’s best practices.
3. Do not attempt to service a system under ammonia charge unless it has been directed by DTC management. We occasionally cut into ammonia system under the practices of ‘Hot Tap Welding.’ We should always perform the required safety checks prior to conducting the hot tap.
4. Do NOT install a relief valve that opens to the atmosphere on a vessel that is full of liquid ammonia or has a large quantity of liquid ammonia. Design for the RV to be piped back to the system as required by codes and IIAR Standards. As a Standard Practice, we do not install dual relief valves on oil pots. Furthermore, we require the relief valve to be piped back to the vessel.
5. We mandate the use of IRC software for design and sizing of RV and RV piping. All DTC engineers must go through IRC training for the use and design of ammonia RV design.
6. Additional ‘Do’s and Don’ts’ of relief valve system (download the full bulletin for details)
7. Ensure there is an updated relief valve list with all the data, such as manufacture, model, capacity rating, pressure setting, location, etc.
8. Perform a Pre-startup construction check list with an updated relief valve list to ensure the correct RV is installed at the right location prior to charging the system with ammonia.
9. Prepare an action item plan for every relief valve for an unlikely opening of relief valve to ensure the valve is accessible with SCBA.
10. Finally, none of the above provisions will offer any safeguard without training of our refrigeration personnel. Remember, no organization or program will ever succeed without a training and performance validation. Without it, none of the above matters.