3 Levels of Sanitary Vessels

Depending on the application, processors serving food or other hygienic industries have varying degrees of compliance requirements for custom vessels.  When working with your custom vessel manufacturing partner, it is important to identify the level of sanitary compliance in the pre-engineering discovery phase.

Apache defines three categories of sanitary design to help customers with the type of sanitary specifications for construction and fixtures to meet the vessel’s process goals.


The base level sanitary vessel is cleaned manually. Typical construction fixtures include threaded coupling, threaded dip tubes and ANSI flanges.  Depending on the application, stock vessels may be used or modified. The material is 2B/Mill, or 304 or 316 stainless and is pickle passivated.

Customers use base-level sanitary vessels for waste tanks, hydrocarbon storage, food-grade applications, adhesives, and solvents.


The type of sanitation is also a driver for more complexity in the design of sanitary vessels.  In the mid-level category, components are removed for cleaning or COP (clean out of place).

Mid-Level sanitary vessel designs are constructed with 304 or 316 stainless material and feature mechanical finishing and pickle passivation or nitric passivation.

Sanitary fittings are specified in a mid-level vessel from tri-clamp ferrules and tube connections to NA connects, flush mount outlet valves and sight glasses.

Customers use mid-level sanitary design vessels for material columns, solvent tanks, collection vessels, extraction, expansion chambers, mixing and dispensing.  


The highest level of sanitary design vessel is automated to be cleaned-in-place (CIP). A 304 or 316 stainless material is specified for high-level sanitary vessels mechanically finished to less than 32RA (roughness average), with nitric and electropolish chemical finish.

The fixtures in this category are electropolished including tri-clamp ferrules, tube connections, NA connects, sight glasses, j-tubes, dip-tubes, and polished internal coils.

Customers using high-level sanitary vessels are involved in automated processing and manufacturing.  Applications for high-level sanitary designs include WRI tanks, R&D lab equipment, heating, and cooling vessels and nutsche filters. 

Each level of sanitary design can meet ASME UM, ASMEU, FDA, 3-A, CRN, PED, and BPE compliance requirements.

When exploring the project parameters for a custom vessel, our guide, “3 Levels of Sanitary Design Tanks and Vessels” , helps to drive conversations and specifications that will meet the vessel’s application, timing, and compliance requirements.

Apache Stainless Equipment Corporation manufactures stainless equipment for a range of hygienic industries. Apache uploads compliance engineering expertise in beverage, biotechnology, pharmaceutical, cannabinoid, food processing, and life science industries.