Wetted materials and surface finish to a stated specification, hygienic connections such as tri-clamp, no crevices or dead legs, food-contact compliant elastomers, and a design that can be cleaned in place or stripped without disturbing pipework. It is a documented specification, not a description of cleanliness.

Circulating detergent and rinse through the assembled system without dismantling it. The pump must have no internal surface that flow cannot reach at cleaning velocity, no dead legs, and seals that tolerate the cleaning chemicals and temperatures. Not every lobe pump is suitable, so it should be confirmed rather than assumed.

A rougher surface retains residue in its texture that cleaning cannot reliably remove, giving microbial growth somewhere to start. Sanitary pumps are polished to a stated roughness value, and that figure is what an auditor asks for. It is a measurable requirement rather than a matter of appearance.

Material certificates for wetted parts, surface finish records, and compliance statements for elastomers against the relevant food-contact regulations. On pharmaceutical work, additional qualification documentation is usually required. These form part of the hygiene system's evidence and are far easier to obtain at purchase than afterwards.

Minutes on a well-designed pump - the front cover and rotors come off without disturbing the pipework or breaking the pump out of the line. That matters because inspection frequency is usually set by the hygiene regime, so a pump that is slow to strip either delays production or gets inspected less often than it should.

Usually a single mechanical seal, or a double seal with a flush where the product would crystallise or where sterility must be maintained. The choice follows the product and the cleaning regime rather than pressure alone, and the flush arrangement itself has to be compatible with food or pharmaceutical contact.

They can, and it is one of the main reasons to choose them - fruit pieces, meat and vegetable chunks and similar pass through the open cavities intact. Rotor profile and clearances set the particle size that can pass, so the product should be described when specifying rather than just named.