Cathodic Protection in 3 Easy Steps

April 1, 2025

The National Fire Protection Agency’s Liquified Petroleum Gas Code 58 requires routine cathodic testing requirements for underground propane tanks 2011 and newer. Are you aware of how to meet specific code requirements efficiently? Requirements vary depending on location, but what doesn’t change is the best way to document your testing data. Here are our suggestions when it comes to complying with NFPA 58 cathodic protection inspection requirements.

Step 1: Improve Accuracy of Cathodic Documentation

Does your company have initial testing and inspections forms for any employees who need them? Do you have a process in place to ensure that periodic intervals are being taken care of? There are a variety of different platforms out there; some people use paper forms, while others use a digital platform to store their documents safely and get reminders of periodic inspections.

Regardless of how you plan to document periodic inspections, ensure you choose something that works well for your company, employees, and customers and meets documentation industry standards. Your plan should also clearly define how your company performs such inspections.

Step 2: Know What’s Required by NFPA 58

Is everyone on your team who performs cathodic protection inspections aware of NFPA 58 requirements? As inspections come in, the P3 Compliance System evaluates technician performance. You’ll be able to view technician-specific data, identify any areas for improvement, and provide customized coaching to reduce risk.

NFPA requirements include:

Cathodic protection must be at least -.85 D.C. or more (meaning negative) using a copper-copper sulfate half cell.
Test must be completed upon installation unless prohibited by climatic conditions, in which case testing shall be done within 180 days after installation of the system.
For continued verification of the effectiveness of the system, retest 12 to 18 months after the initial test.
Systems failing a test shall be repaired as soon as practical unless climatic conditions prohibit this action, in which case the repair shall be made not more than 180 days thereafter. Testing schedule shall be restarted as required initially.
Periodic follow-up testing shall be performed at intervals not to exceed 36 months.
Documentation of the results of the two most recent tests shall be retained.

Step 3: Find a Bulletproof Way to Track Follow-Up Tests

First, it’s critical to develop a plan to conduct required follow-up testing. And keep in mind—paper inspection forms stuffed in a filing cabinet or PDF forms lost on your computer have no way of letting you know when they’ve expired. Instead, P3’s digital documentation and smart forms automatically flag inspections needing follow-up on your dashboard for management staff to see.

Using the P3 Compliance System to store, retrieve, and track cathodic protection documentation makes this process extremely efficient for your safety management team. Plus, software can notify you immediately when corrective action is necessary, unlike paper forms which often sit unattended for months.

Looking for more information about cathodic testing? Check out this webinar from P3 Propane Safety about best practices for cathodic testing inspections.