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Why Your Chemical Tank Needs Professional Inspection And Testing

When storing any type of chemical, it’s important to conduct routine annual tank inspections to make sure the tanks, fittings, venting, and accessories are in good working condition. You can perform a basic tank inspection on your own by following our installation manual, or the system can be inspected by a Poly Processing field service technician. We recommend having a professional perform an in-depth inspection with testing every 3-5 years.


What’s the difference between an inspection you can do and a professional inspection? Here’s an overview of the inspection and testing our field service technicians perform on your chemical storage tanks.

Comprehensive Visual Inspection

A close inspection of the chemical tank’s exterior can uncover cracks or crazing caused by UV degradation and other stressors. If cracks are present, a field technician may scrape off a small bit of the surface of the tank to see how deep the cracks go. If they are at least 1/32” deep, further testing may be required.

As long as the tank is empty, the field technician can ultrasonically measure the tank wall thickness. This will tell us if any corrosion is eating away at the sidewall, an indication of dangerous tank wear and tear. The technician can also insert a camera inside to take photos, which will show any degradation or interior cracking.

Download our Tank Installation Manual for instructions on do-it-yourself annual inspections.

Testing The Tank Material Itself

One of the best ways to test the actual polyethylene of the storage tank is to take a sample for impact and gel testing. This will tell you if the tank is holding up under the stress of the chemical, or if it’s reaching the end of its useful life.

The ASTM-D 1998 impact test and gel test reveal if the material has become brittle. We take a sample from the dome and plug it with a bulkhead fitting. Normally we can take a sample from the dome area and seal the hole with a fitting with a plug in it or a blind flange. The sample is sent back to the lab for testing.

When a field service technician inspects your chemical tank system, they will also verify the chemical and tank compatibility. This is especially important if you have changed the chemical being stored in your tank.

P1019617 (1)Testing Fittings, Gaskets, Venting and More

Even if the structure of the tank itself seems secure, it’s important to test the fittings and attachments for signs of wear. Often, a field service representative can replace a fitting or gasket onsite. The technician will also inspect restraints, ensure seismic clips are spaced properly, and inspect ladders and brackets for signs of corrosion.

Venting is critical to the life of a tank, and it’s important to inspect the vent line for obstructions and for proper vent sizing. Bird nests, bee hives and other obstructions can collect in outdoor vents, and dust and other debris can collect in indoor lines.

Getting Your Results

All the findings are presented with photo documentation and recommendations for repairs or replacements. The report will also make a recommendation on the date of the next inspection, based on the age and condition of the tank and the chemical application.

Provided the tank is empty on the day of inspection, the tech can also insert a camera inside the tank to take pictures to show if there is degradation and/or cracking on the interior.

All the findings are presented, with photo documentation, with recommendations for repairs or replacements. The report will also make a recommendation on the date of the next inspection based on the age and condition of the tank and the chemical application.

To learn more about tank inspections and to schedule a professional tank inspection, talk to a field service expert today.

Contact Our Field Service Department

Topics: Installation and Service