Meeting expectations for medical tubing

Olympus highlights two important standards for medical tubing, and explores inspection solutions that can help you meet them.

Meeting strict standards for medical tubing with precise inspection tools

Medical tubing is used in many applications, such as blood transfusions. Consequently, medical device manufacturers follow strict industry standards to ensure medical tubing products are reliable and safe for patient use.

The challenges of meeting standards for medical tubing

One important standard for medical tubing is non-adhesiveness. Non-adhesiveness is achieved by making the surface of the tube’s inner wall as smooth as possible. While some level of roughness is needed to prevent air bubbles from forming in the tube, the roughness must not interfere with the tube’s transparency.

Manufacturers must quantify the roughness of their tube’s inner surface to ensure they meet the standards. Yet, measuring roughness can be difficult since some tubes have a special coating on their inner surface or have a small diameter.

Wall thickness is another critical specification for medical tubing products, and there are often tight tolerances that need to be met. However, measuring wall thickness can be difficult as tubing becomes increasingly miniaturised for noninvasive procedures.

Precise inspection solutions for meeting strict medical tubing standards

Strict standards for medical tubing products are met through precise inspection solutions. Here are two tools that can help:

1. 3D laser scanning confocal microscope

3D laser scanning microscopes can precisely measure the surface roughness of a medical tube’s inner wall. The microscope scans use a laser to acquire detailed, accurate, and repeatable surface data. It does so without damaging the tubes, even if their inner surface is coated. This nondestructive method minimises the risk of inaccurate roughness data caused by damage to the tube’s inner wall.

2. Ultrasonic Testing (UT)

Another helpful technology for meeting strict medical tubing requirements is UT. This can precisely measure the wall thickness of medical tubing with tight tolerances, such as catheter tubes and extruded tubing.

UT is a nondestructive method to characterise the thickness or internal structure of a test piece using high-frequency sound waves. These sound waves will travel through a medium (e.g. a piece of plastic) until they encounter the boundary of another medium (like air), at which point they reflect back to the source. By analysing the reflections, you can easily measure the wall thickness of small-diameter medical tubing.

To measure the wall thickness of medical tubing with UT, you need two pieces of equipment: A transducer and an ultrasonic thickness gage. The appropriate transducer type, size, and frequency vary based on the application.

Conclusion

As demand for smaller and more sophisticated medical tubing products continues to increase, diverse technologies like these are improving the quality assurance process for medical tubing manufacturers.