A common situation we find is that facilities struggle to understand how their “initial start-up” procedure for a new piece of process equipment can/will differ from their other start-up procedures for the equipment (e.g. normal, after a turnaround, after an emergency shutdown, etc.). Recently I have learned of a process used on galvanized condenser coils/tubes that will aid in the “prevention of premature failure of the protective zinc layer on a hot dip or mill galvanized steel“… Galvanized Steel – Passivation. The facility which I was working with just happened to mention it as they had just added some new condensers. Having never heard of it, we took about 30 minutes to discuss if this “treatment” was part of PSM/RMP and where it would fit into PSM/RMP management systems. As it turns out, it has very STRONG linkage to the PSM/RMP efforts and for those that agree that it is part of PSM/RMP, it is a PERFECT example of how an “initial start-up” procedure will be DIFFERENT from the other start-up procedures.
Taken from a condenser manufacturer’s recommendations…
“Galvanized Steel – Passivation” is a treatment that prevents “White Rust” which leads to premature failure of the protective zinc layer on a hot dip or mill galvanized steel. This problem can occur as a result of improper water treatment control during the start-up of new galvanized equipment (makes the argument that our water treatment aspect of our process MAY be critical to process safety!). The initial commissioning and passivation period is a critical time for maximizing the service life of galvanized equipment. EVAPCO recommends that the site-specific water treatment protocol includes a passivation procedure which details water chemistry, any necessary chemical addition, and visual inspections during the first six (6) to twelve (12) weeks of operation.
EVAPCO even provides us with our SAFE OPERATING ENVELOPES for our Initial Start-up Procedure! Now we have our Safe Upper and Lower Limits (as shown below), but we still need to develop the consequences of deviation and steps to correct/avoid these deviations and these may be very short and simple – but they MUST be part of our procedure! We will also need some means to measure and monitor these safe upper and lower limits during this 12 week period, but this could be done via portable devices that need to be calibrated, but will NOT become part of our longstanding list of PSM/RMP critical equipment.
During this passivation period, recirculating water pH should be maintained above 7.0 and below 8.0 at all times. Since elevated temperatures have a harmful effect on the passivation process, the new galvanized equipment should be run without load for as much of the passivation period as is practical. The following water chemistry promotes the formation of white rust and should be avoided during the passivation period:
1. pH values in the recirculating water greater than 8.3.
2. Calcium hardness (as CaCO3) less than 50 ppm in the recirculating water.
3. Anions of chlorides or sulfates greater than 250 ppm in the recirculating water.
4. Alkalinity greater than 300 ppm in the recirculating water regardless of pH value.
(Source: EVAPCO – Operation and Maintenance Instructions and EVAPCO’s Engineering Bulletin 36 – White Rust on Galvanized Steel)
So now that we know what “passivation” is and that the manufacturer RECOMMENDS we do it to their equipment in order to prevent “premature failure of the protective coating” on the galvanized steel, one has to ask… “Is this now a manufacturer recommendation” thus making this part of our PSM/RMP program? I would say without hesitation that YES this becomes part of our PSM program. In fact, I would argue that it would touch the following elements: PSI, PHA, SOP, MI, PSSR, and even Contractors if we contract out the task.
Sure one could say we are not going to do the passivation on our tubes/coils and that this will only lead to a shortened life span of the condenser and does not increase my risk to a catastrophic release, thus no connection to PSM/RMP. But we could say this about every piece of equipment in our process; the bottom line is that when a manufacturer “recommends” an action be done to install, operate, and maintain their equipment, this is the first line of RAGAGEP. Should we choose NOT to follow these manufacturer’s recommendations, then the burden is on the owner/operator of the equipment to explain how they are ensuring their change from the “manufacturer’s recommendation(s)” is being safely managed. The one thing I would point to is that the manufacture in question does NOT provide a PM schedule based on if passivation is done vs. it not being done. They seem to be pretty intent on it being done is the RIGHT THING TO DO, but of course, they can not force the owner/operator to do anything.
There are some that will argue that the loss of the zinc coating is long ways from an incident involving tube/coil failure, and the fact that this passivation ONLY protects the zinc coating and does nothing to protect the metal underneath means that this is not part of PSM/RMP. I would argue that once the galvanized metal became our “materials of construction” for this equipment, the effort to protect the “galvanized coating” directly links the materials of construction to PSM/RMP. If we want to use carbon steel as our material of construction for the tubes/coils then this is all a mute point. But when we spec out “galvanized tubes” then this material of construction becomes part of our PSI and the tasks the manufacturer “recommends” we do to protect this coating just draws this process further into our PSM/RMP program. The argument that the loss of the galvanized coating is NOT an issue will be VERY HARD to prove once OSHA/EPA reads the manufacturer’s literature!
But let’s say we are going to follow the manufacturer’s recommendation and do the passivation treatment to our new condenser. This is done on NEW condensers and done as part of the “initial commissioning/start-up“. The manufacturer’s engineering data sheet states:
White rust is most likely to appear on new equipment as it is being put into service. The initial few weeks, when zinc is exposed to water, must be carefully controlled since this is the period where the metal is most prone to white rust attack.
I would also like to point to their operations and maintenance manual which states:
The initial commissioning and passivation period is a critical time for maximizing the service life of galvanized equipment.
So where is all this going…
1910.119(f)(1)(i)(A) Initial startup
As the manufacturer even uses terms such as “initial commissioning” and also states “EVAPCO recommends that the site-specific water treatment protocol includes a passivation procedure which details water chemistry, any necessary chemical addition, and visual inspections during the first six (6) to twelve (12) weeks of operation“. I just don’t see how anyone could argue that if you are doing the recommended passivation treatment during the commissioning of the condenser that the passivation procedures would not be a PERFECT FIT for the “initial startup” procedure for the equipment. This is just a PERFECT example of how an “initial start-up” for this condenser will differ from:
1910.119(f)(1)(i)(G) Startup following a turnaround, or after an emergency shutdown
In my eyes, the passivation treatment would EASILY be a “manufacturer recommendation” (e.g. RAGAGEP) to aid in the “premature failure of the protective coating on the galvanized steel“. I just don’t see how anyone could make a strong argument in not doing this treatment. But there is more!
In the manufacturer’s Engineering Data Sheet #36, they state in all bold font and underlined…
Before any water is added to a new piece of galvanized equipment, the equipment operator should have a detailed plan for passivation of the galvanized metal and continued water treatment after passivation
Keeping it simple, when the manufacturer of a piece of equipment provides us with the initial commissioning and the instruction that their equipment, using galvanized metal, is to be exposed to treated water… I just find it hard to understand how passivation does not fit into our PSM/RMP programs and now I have the PERFECT example of how an initial start-up procedure will be different from the other start-up procedures!