My Experience with Passivation

In a few seconds my work shoes transformed into flip-flops. I looked down and could see my toes.

Here's the setup:

I was the lone worker on a U-shaped Electroless Plating line in a job long, long ago. Everything moved from right to left as we ran parts through a process that dipped them first in an acid vat, (a process called passivating) and then a rinse tank, and then on to the other steps. I'm right-handed, and the line felt a tiny bit backwards to me. This incident happened point in the process the end of the U, where there was a small gap between the acid tank and the rinse tank.

The acid tank was 50% Nitric acid and 50% something else equally nasty. I can't remember which other kind of acid it was, but it was definitely another similar acid. The resultant mixture looked like water and smelled like fireworks. My job was simple. I'd dip in a bucket of parts, swish it around for a specified time, and then lift it, let it drain on the edge of the tank, and get it in rinse water as fast as possible. The goal as I understood it was to minimize exposure to the air in the time between the acid bath and the rinse tank.

I did the task the same way every time and it became second nature. Until that day.

Here was the error:

On that day, I somehow stepped into the gap between the two tanks, and instead of turning to the left to get the bucket from tank to tank, I turned my body to the right. I suppose my left arm was tired perhaps. I didn't think about it. I just turned the wrong way.

A tiny stream of acid dripped from the bottom of the bucket and went across my shoes. It was just a trickle.

I dropped the bucket into the rinse tank and immediately pulled armloads of water onto my legs. In the time it took me to realize the error, and get the water to my shoes, the acid ate through my shoes and most of the way through my socks.

It's a simple story. I didn't get hurt. I hadn't followed the process. I didn't think much of it. I was more embarrassed than anything else. No one was around. Nothing in my training told me what to do if something like that happened.

When I reflect on it now:

• I'm thankful I wasn't injured, and very thankful the work shoes provided as much protection as they did.
• If I could go back and observe the situation, I wonder exactly how many potential improvement points I'd notice with the perspective I've gained in all of the years since.
• That simple incident in which no one was hurt actually contained everything the factory leaders for that company needed to know to improve and errorproof that process. Process training, error-proofing, safety training, standard work, leader standard work, the culture of how errors are viewed and discussed -- all of those elements could be surfaced and addressed without waiting for a 'lost time' injury to trigger them.

In a later role in a different company, one of my supervisors talked about need to have processes and controls that prevented errors from happening rather than just ones that spot defects after the fact. He said: "By the time something appears on a report, it might be too late."