In May of 2015, IIAR was notified that inspectors with the Illinois State Fire Marshal were requesting that ammonia vessels as part of refrigeration systems be internally inspected. Representatives from the IIAR met with the Division Chief and several members of the Illinois Board of Boiler Rules in June of 2015 and presented the case that internal inspections for vessels in ammonia refrigeration systems need not be internally inspected for a number of legitimate reasons, the foremost being that internal corrosion has never been observed in ammonia refrigeration systems.

Subsequent to this meeting, the Division Chief agreed to write an inspection procedure for ammonia refrigeration vessels and submit it to the board for approval. Unfortunately, he was not able to accomplish this before his retirement. When it became apparent that the proposed procedure had not been approved, the new Division Chief was contacted and briefed on the situation. After a period of consideration, the Division Chief informed the IIAR that inspectors will not be required to request internal inspections for ammonia refrigeration vessels, but that the proposed procedure for inspecting ammonia refrigeration vessels would not be considered. The result is that inspectors from the agency can still request internal inspections if they desire, although it is not likely.

Rather than insist on a formal special inspection procedure for ammonia refrigeration vessels or a public statement of intent, IIAR decided that a better approach would be to address the source for Illinois’ general inspection requirements, which is the National Board Inspection Code. IIAR will examine the current inspection rules and determine if special exceptions are warranted for ammonia refrigeration vessels. In the likely case that engineering analysis supports changes, these will be submitted to the NBIC for consideration. This effort is in its early stages and will probably take many months.

In the meantime, we request end-users and contractors working in Illinois to alert IIAR to any requests or demands for internal inspections of ammonia refrigeration vessels. We will offer assistance in challenging the request and consider re-approaching the Illinois State Fire Marshal’s office if the notices become prolific.