Not all certifications are equal. Some look good on a wall; a handful actually change which jobs you can get and how plants value you. Based on what employers ask for in the listings on this site, these five come up the most.
1. PLC / Controls training
The single biggest skills gap in most plants. Techs who can go online with an Allen-Bradley processor, read ladder logic, and trace an I/O fault are consistently the hardest to hire. There’s no one universal credential here — what matters is demonstrable competence with Studio 5000 / RSLogix (and increasingly Siemens TIA Portal). Community college controls courses, manufacturer training, and home practice rigs all count. Roles that lean on controls skills are usually the best-compensated non-supervisory jobs in the building.
2. Journeyman electrician license
In many states, an industrial maintenance electrician role requires or strongly prefers a journeyman card. It’s a long road (typically 8,000 supervised hours plus an exam), but it’s the most durable credential on this list — it follows you across employers and states, and it separates you from mechanics who “do some electrical.”
3. EPA 608 (HVAC/R)
If a plant has refrigeration — food and beverage, cold storage, plastics chillers — somebody on the maintenance team needs a 608 card to legally handle refrigerants. It’s an inexpensive exam you can prepare for in weeks, and it instantly makes you eligible for HVAC/R maintenance roles that many mechanics can’t touch.
4. AWS welding certifications
Most maintenance welding is uncertified repair work, but an AWS D1.1 structural cert (or even documented proficiency in stick and MIG) matters for millwright-leaning roles — conveyor repair, structural work, equipment installs. If you’re aiming at millwright jobs, this is the one to prioritize.
5. CMRT (Certified Maintenance & Reliability Technician)
The SMRP’s CMRT is the closest thing to a general-purpose “I know maintenance” credential. It tests maintenance practices, preventive/predictive maintenance, and troubleshooting fundamentals. It’s less commonly required than the others, but reliability-focused employers recognize it, and it’s a strong differentiator for senior tech and lead roles.
The order that makes sense
If you’re early-career: EPA 608 first (cheapest, fastest), then PLC coursework, then welding if your plant does structural work. The journeyman path is a multi-year commitment best started early. CMRT fits best once you have a few years of real troubleshooting behind you.
See which certifications employers are asking for right now on our certifications hub — each page lists live openings that mention that credential.