Catheter Basics

Urinary Catheters come in a wide variety of sizes and materials (latex, silicone, red rubber, and antibacterial) Catheters are sized using a measurement called French (Fr). French size is a standard for medical tubing outside diameter. Developed by a French physician in the 1800’s, it is a measurement of tubing circumference.

You can tell the French size of the catheter by the color of its funnel end.

catheter-size uti-cath-chart

Consult with your physician about which catheter French size is right for you.

Funnels serve several functions:

  1. Permits he catheter to be attached to leg bags or night bags
  2. Irrigation of the bladder
  3. Used to insert medication into the bladder.

One French is approximately 1/3 of a millimeter 0.013 inch. The larger the French number the larger the outside diameter. Sizes typically range from 5 Fr – 20 Fr.

Size 14 Fr. or size 16 Fr catheters are most commonly used in adults.

There are three different lengths available for catheters: male, female, and pediatric.

  • Male length catheters are usually 16 inches in length.
  • Female length catheters range from 6-8 inches in length.
  • Pediatric length catheters typically range from 8-10 inches in length. Women and children generally use shorter lengths because of their shorter urethral length.