Ever order hundreds of feet of plastic tubing or hose and then found it inappropriate for the application? And was the equipment unusable or production halted while waiting for a replacement product? If so, the following tips can help avoid similar situations by noting a few selection details that were probably overlooked.

1. Failure to check for approved or incompatible ingredients

   Must the selected tubing or hose be manufactured with FDA, NSF (National Sanitation Foundation), Class VI, 3A, or other association-approved ingredients? Also consider incompatible fluids. Might the anticipated flow react with the tubing or hose material? If a medical application calls for specific association approvals, check for this information in supplier catalogs or spec sheets. If you do not know whether the application calls for association-approved ingredients, ask an informed source.

2. Unaware of pressure or vacuum requirements

   Will products travel through the tubing or hose under pressure or by vacuum? Certain tubing materials cannot handle these situations. Reinforced hose may be the better answer. In fact depending on their reinforcement (polyester braid, fabric, stainless steel wire, corrugation, or convolution), certain hose are well suited for pressure applications while others are better for vacuum. The durability of medical tubing or hose under constant pressure or vacuum comes into question as well. For instance, if the application is for a peristaltic pump, tubing longevity is an important consideration.

3. Failure to identify the operating temperatures

   Can the tubing or hose under consideration withstand the temperature of the liquid traveling through it, as well as the external temperature? High and low temperatures may be involved. Certain tubing materials, such as silicone, can withstand fluctuations in temperature, while others perform better at constant temperatures. Also, keep in mind that the higher the temperature, the lower the pressure the tubing or hose can handle.

4. Neglecting to check for flexibility and resistance to kinking

   Will the tubing or hose bend around other parts or machinery in the application? If so, use products manufactured with characteristics to prevent kinking. Does the application involve repetitious movement, as it would on a robot? The tubing or hose selected must withstand repeated flexing. Whipping hoses can lead to personal injuries. And, if the application involves rubbing the tubing or hose against other equipment, make sure the product can withstand the abrasion.

5. Failing to know if the tubing or hose will impart a taste or odor to the product flowing through it

   Some tubing and hose materials do not transfer taste or odor. When the application involves items such as medicines or laboratory fluids, taste or odor transferred to the fluid could be of critical concern. Also, some tubing and hose materials contain plasticizers to help them stay flexible. These occasionally leach out, thereby contaminating the product. Other materials (silicone and polyurethane, for instance) are naturally flexible and need no plasticizer.

6. Not knowing if conveyed products must be viewable in the tubing or hose

   Must the user see the product flow to check for consistency, dosage levels, or to note measurements? Make sure you're aware of the eventual application of the tubing or hose and whether products must be visible. Both transparent and translucent tubing and hose materials allow for visual contact with the flow.

7. Failure to ask whether the tubing or hose can be cleaned and reused

   Will the tubing or hose withstand sterilization by a specific cleaning agent? Is the chemical in the cleaner safe for the application? Can the hose be autoclaved, and how often? Does it simply flush clean or can the hose withstand low-pressure steam sterilization? Answers to these questions could save money and impact safety.

8. Not knowing your packaging requirements

   Is a 100-foot coil of tubing or hose acceptable? Or do you need twenty pieces, each 5-ft long? Must it be bagged, double bagged for extra cleanliness, boxed, or are stacked coils on a pallet acceptable? Knowing how the tubing or hose will be used can help determine its packaging, allow for easier handling, and result in less waste. Depending on the type of material, coils of tubing and hose may have a coil set or permanent curve. There are options for producing tubing and hose that remains straight.

9. Neglecting to explore custom options

   This closely relates to the packaging requirements. For instance, if the end use of the tubing or hose requires cuting it into 6-in. pieces, have it delivered that way. Doing so saves labor and costs. Other customization can include special colors, shaped parts, thermally bonded tubing (two or more tubes attached to each other along their sides), printed products for identification, or hose assemblies. Don't consider only stocked products — know the ultimate use of the tubing or hose to determine if a custom product will be a better choice.

10. Forgetting about fittings and clamps

    Most cases must attach the tubing or hose to other equipment. Fittings and clamps come in many different materials, from nylon to PVDF, fluoropolymer to stainless steel, so users can select the best match for the application. It is possible to build a system from one material (polypropylene, nylon, polyethylene, or fluoropolymer). Remember that the fittings' material must be compatible with your application because the flow will also contact the fittings.