Autonomous Maintenance Step 2: How to Eliminate Sources of Contamination

Your operators just finished the deep clean. The filler looks better than it has in years, every defect is tagged, and the crew is proud of it. Two weeks later, it's coated again.

That's the point where most programs lose the floor. Operators clean the same oil film off the same guard every shift and start to wonder what the deep clean was for. Fix what makes the machine dirty and cleaning gets shorter, inspections get easier, and the tags from step 1 turn into real repairs. Skip it and you've built a cleaning routine that never ends.

Step 2 of autonomous maintenance is where you stop the mess at its source. This article covers what counts as a contamination source, why hard-to-access areas belong in the same step, how to run it on one line, and where it usually goes wrong.

What is step 2 of autonomous maintenance?

Step 2 of the 7 steps is "eliminate sources of contamination and hard-to-access areas," listed in older TPM materials as Countermeasures for Contamination. It takes the defect list from step 1 (initial cleaning) and asks one question of every recurring mess: what is causing it, and can we stop it?

The second half matters as much as the first. An area that takes 20 minutes and a ladder to reach won't get cleaned or inspected on a busy shift, however good your standard is. Step 2 makes those areas reachable before step 3 writes them into a CIL standard.

What counts as a source of contamination?

Anything that puts material where it doesn't belong on the equipment. In food and CPG plants, most of it falls into five groups.

Why hard-to-access areas belong in step 2

If a check point sits behind three fixed guards, it will be skipped the day the line is behind. That isn't an operator problem. It's a design problem, and step 2 is where you fix it.

Common fixes are inspection windows or clear guards, quick-release fasteners where a lockout procedure allows them, relocated lubrication points, and remote grease lines. Each one cuts the time a CIL takes, which is what keeps step 3's standard realistic.

How to run step 2 on your pilot line

Where step 2 goes wrong

• Sources get noted, never fixed. If operators report the same leak every week and nothing happens, they stop reporting it, and the step quietly stalls.
• Everything goes to maintenance. Many fixes are small enough for operators to make with a technician's sign-off. Routing all of them to the maintenance backlog buries the team you're trying to free up.
• No baseline. Without step 1 cleaning times, you can't show the floor that step 2 made their shift easier.

How Weever helps with step 2

Each contamination source becomes a corrective action with a photo, an owner and a due date, with reminders until it's closed. Operators can see what happened to the issue they reported. Supervisors see what's open by machine and by age.

That visibility is what turns a backlog around. Royal Canin's Lebanon, Tennessee factory had over 300 unresolved issues before moving to Weever. By late 2024 it had captured nearly 3,000 abnormalities with a 95% close rate.

Next: write the standard

Step 2 is done when the main causes of recontamination are fixed or owned, and the hard-to-clean areas are easier to reach. Then you're ready for step 3: establishing CIL standards.