Laboratory tubing comes in a variety of materials that offer different costs and benefits. When selecting a laboratory tubing material, one must take into account cost, rigidity, opaqueness and chemical sensitivity to the solution that will be passing through it.

Glass is very breakable, but it gives a 100 percent unobstructed view of the solution passing through it and of the meniscus, even if the solution is clear. Vinyl offers the lowest cost, but is chemically sensitive if the solution involves acids or alkylines. Silicone tubes are less sensitive chemically because they contain only polymerized silicones. And polyethylene tubes are the best choice if you're working with solutions under fairly high pressure. When shopping for laboratory tubing, consider the following:

1. Use vinyl tubing to keep costs low if strong acids and alkylines will not be passing through them.

2. Opt for silicone tubing for applications requiring an absence of plasticizers.

3. Grab polyethylene laboratory tubes when working with higher pressures.

4. Acquire lab glass tubing for applications that require a clear view and chemical inertness.

Action Steps
The best contacts and resources to help you get it done

Get vinyl lab tubing to keep costs low if strong acids and alkylines will not be used

For applications involving dilute acids and bases and for most other aqueous solutions, choose vinyl tubing. It's the cheapest and most commonly used material for laboratory tubing. Just don't select vinyl for use with organic solvents or the plasticizers in the vinyl will migrate into the solvent. Moreover, the tubing will become embrittled over time.

I recommend: Laboratory tubing supplier Spectrum Chomatography carries a good selection of vinyl laboratory tubing online, as does The Lab Depot.

Utilize silicone laboratory tubes in applications requiring an absence of plasticizers

Though somewhat more expensive, silicone tubing contains no plasticizers to leach out. Silicone is therefore suitable for use with most solvents. It's translucent white, so you can see light through the tubing and can make out the meniscus, albeit not shapes, through the tubing. It's best suited for shorter contact periods (i.e. 24 hours or less) and the temperature should be normal.

I recommend: Suppliers of laboratory tubing Saint-Gobain Performance Plastics and Environmental Equipment and Supply offer a full array of silicone laboratory tubing products for you to choose from. Alternatively, Pelmore Laboratories is a great source if you have a requirement for laboratory rubber tubing or other laboratory tubing supplies.

Reach for polyethylene laboratory tubes when working with higher pressures

Polyethylene tubing is able to withstand significantly higher pressures, as it is a 'semi-rigid' tubing material. It's still translucent, but far more opaque than the vinyl and silicone types; thus, you won't be able to make out the location of the meniscus or the presence of an air bubble. It also makes for a neater and more organized-looking work area.

I recommend: Instech Labratories is a very good source of polyethylene lab tubes. They extrude their own tubing in order to contain costs. Becton, Dickinson also is a great supplier of polyethylene lab tubing, but their tubing is designed for the medical industry.

Acquire lab glass tubing for applications that require a clear view and chemical inertness

Laboratory glass tubing is fragile, but it lets you see very clearly the location of the meniscus and of air bubbles, plus you know it's not going to react chemically with the solution. Borosilicate glass tubing is a higher quality version of glass tubing and has the same coefficient of expansion as Pyrex.

I recommend: ScienceLab and Online Science Mall, both laboratory tubing suppliers, carry an array of glass tubing products for the laboratory.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  In trying to decide on a tubing material to use for a critical application, always do an immersion test. Immerse a short length of the lab tubing in a closed container of the fluid for 48 hours and then examine it for signs of swelling, attack, embrittlement or forms of deterioration.