Understanding API 653 Inspections for Aboveground Storage Tanks

Tank Inspector at WorkRegular tank inspections are important to maintain the quality and longevity of storage tanks.

Under the API 653 standard developed by the American Petroleum Institute, site operators must conduct regular monthly inspections and contact API 653 certified inspectors to conduct internal and external inspections every 10 and five years respectively.

The inspector then drafts a recommendation of repairs and alterations required based on the results of their review.

What is API 653?

API 653 tank design standard provides the standards for the inspection, repair, alteration, and reconstruction of aboveground storage tanks in the oil and petroleum industries. The standard covers atmospheric welded or bolted storage tanks with a design following the API 650 and AP12C standards.

If there are any conflicts between both standards, the protocol is to follow API 653.

Importance of API 653 Inspections

API 653 inspections allow you to identify worn out or damaged parts and perform repairs or replacements before any significant leaks occur. They also allow you to prevent contamination of your secondary container or groundwater, which may cause environmental concerns.

API 653 Inspector Qualifications

The API 653 standard requires monthly inspections by persons knowledgeable on handling storage tanks. However, all facilities are required to undergo API 653 testing by certified inspectors who have passed an examination conducted by the API.

Each certified API 653 inspector has his or her own inspector number. They are also required to undergo testing every three years to ensure their knowledge is up-to-date.

Components for Inspection

During an internal inspection of a tank, the inspector measures the thickness of the bottom and annular plates. They also look at the shell plates, roof plates, gauge pole, and support structures for signs of corrosion or deformation.

The same shell, bottom, and roof plates undergo checking during external inspection, as well as the side vents, flange points, pontoons, weather shield, and painting and insulation.

These are the basic things you should know about API 653 inspections. Make sure you follow the rules as you go.