$15 - $20

411-0018-038 Last-O-More Tubing 3x5 mm per Meter by WatchGas

Regarding sampling tubes for gas detectors, many manufacturers promote clear tubing as a cost-effective solution for drawing air from confined spaces. While affordability may be a key selling point, it's essential to recognize the limitations of clear tubing in gas detection.

In the automotive industry, clear tubing is avoided for crucial systems like fuel and windshield fluids because it lacks the necessary inertness. The same principle applies to gas detection. Some argue that clear tubing offers two benefits: it allows visibility of fluid intake, and discoloration signals the need for replacement. However, once a fluid is drawn into the tube, contamination of the inner walls occurs, requiring immediate replacement. Best practices call for avoiding fluid intake altogether, which is why devices like ball floats are used—visible, such as the yellow one pictured.

Discoloration of clear tubing often points to a reaction between the sampled gases and the tubing material itself, proving the material's unsuitability rather than providing a reliable replacement indicator.

Inexpensive aquarium tubing made from PVC is commonly repurposed for gas detection, but PVC's inherent odour is a clear sign it's not suitable. While there are other, more promising materials—such as those with Teflon inner linings—these are no longer cheap, and Teflon can flake, causing blockages.

That's why we developed Last-O-More tubing, made from fluorinated elastomer (rubber). It's inert, doesn't flake, is highly flexible, and resists binding. Plus, it's explicitly marked as a gas sampling tube to ensure correct use.

While not the cheapest option, Last-O-More tubing has been rigorously tested in the lab using GC analysis. It has proven to be the best in absorption and retention—retention, meaning the release of absorbed gases when exposed to heat (like sunlight).

Last-O-More tubing is black, so always pair it with a ball float or water trap (filter) and replace it when it no longer feels slippery. Proper tubing is critical in gas detection—don't compromise safety.