Endoscopy Products & Equipment
Endoscope Repair


Home > Endoscopes Articles > Flexible Endoscope Leak Testing

Flexible Endoscope Leak Testing


HMB Leak Tester
Flexible Endoscope Leak Tester

Leak testing is the most efficient and least expensive method available to detect any dangerous opening inside the flexible endoscope that could lead to fluid invasion and extraordinarily expensive repairs.

Endoscopes are complex devices that mix sophisticated electronic components, mechanical components, fiber optic illumination, micro optical lenses and video elements together. None of these react well to fluids.

As a result, endoscope leak testing is a crucial part of proper scope cleaning and disinfection, but, oftentimes, it is done improperly or not done at all. There are both manual and automated leak testers. Regardless of the type you use, it must be done.

Some of the most expensive and lengthy repairs performed on flexible endoscopes are due to fluid invasion. Most fluid invasion into flexible endoscopes is preventable. However, even when it is not preventable, the damage can be minimized if leak testing is performed on a regular and conscientious basis.

Fluid damage triggers over half of the total endoscope repair costs. Moisture can cause damage as it invades the scope. And the longer fluid remains undetected and unaddressed, the greater the damage to the instrument. Some of the symptoms of fluid invasion are: image stains, foggy image, no image, electronic malfunctions,

Flexible scope manufacturers, government health agencies, and organizations related to the gastroenterology industry all recommend that a flexible endoscope be leak tested after each procedure. These organizations identify leak testing as a core element in their multi-step reprocessing guidelines. Fluid invasion is so disastrous to the scope that some manufacturers and this endoscope repair company even recommend leak testing before and after reprocessing.

One of the most significant changes made to flexible endoscopes was the introduction of completely immersible scopes in the mid 1980s.  These instruments can be completely soaked in disinfecting solutions long enough to be classified as high level disinfected.

Several key changes resulted in the fluid resistant endoscopes we use today. The insertion tube and bending section had always been sealed using a combination of epoxy seals and o ring seals. Today, the entire scope is assembled in any section where two parts of the scope form a seam. Epoxies or other hard sealants are often used when parts are threaded together. The combination of the epoxy and the o ring seals provides a water resistant shell to the endoscope. This shell allows long immersion times in cleaning and disinfection solutions, and it allows for pressure testing the entire scope for leaks. Today, all endoscope manufacturers use similar techniques to make their scopes water resistant.

These water resistant scopes can also be pressure tested for leaks, since they are airtight and because the main components of the endoscope are hollow inside to allow room for the delicate internal components to move and flex.

It is the general hollowness of the endoscope that allows pressure testing to be effective. Pressure entering one section of the scope will travel throughout the entire cavity of the scope. Once pressurized, the flexible scope can be observed for leaks in the water resistant shell. This hollowness, however, also means that fluid entering one area will travel throughout the entire scope. So, fluid entering the light guide connector, for instance, may result to damage to many parts of the scope.

Fluid invasion can occur any time that a flexible endoscope is immersed in fluid.  The following are common points of fluid invasion and possible causes for the water resistant shell to fail.
Bending Section and Bending Sheath – This section is very thin and flexible. It is very susceptible to cuts, holes, tears and nicks from any sharp object.

Insertion Tube – Although more cut and puncture resistant than the bending section, it is subject to the same hazards. Bites and punctures are also a problem.

Control Body ­– Made of plastic and metal, these parts are difficult to damage without impact. However, the o-rings and seals that are used where different parts join together, are extremely delicate. Even slight impact to the control body may cause the seals to misalign, causing a leak.

Electronic Connector – When submerged in cleaning solution, this delicate component is covered and sealed by the soaking cap. Care should be given to make sure the soaking cap is in good condition and properly seated on the electronic connector.

Any fluid entering the internal cavities of an endoscope may do severe or even irreparable damage to its components. The corrosive nature of the fluid will determine the rate at which the damage is done. Highly acidic or highly alkaline solutions will corrode more quickly than water, but any fluid will do serious damage over time.

Flexible endoscopes are subject to severe damage from fluid invasion, but endoscope manufacturers have provided a means for inspecting scopes for leaks. Pressure testing or leak testing can allow a user to find potential leaks prior to immersing the scope in fluid, thereby limiting the problem only to the area affected. When performed effectively and at the correct point in each reprocessing cycle, leak testing can eliminate all but the most extreme circumstances for fluid invasion. Through leak testing, problems are located before they cause further scope damage or cross contamination of patients.

A leak may occur at almost any point in the daily life cycle of the endoscope. A leak test can be performed in 15 to 30 seconds using a hand held bulb and gauge This pro-active approach to leak testing should be performed after every procedure and prior to immersing the endoscope in fluid, thereby preventing expensive fluid invasion repairs. More importantly it insures the integrity of the scope, thereby eliminating potential adverse patient outcomes such as cross contamination of chemicals or proteinaecous materials from antecedent procedures.



Sign Up for HMB's Promotional Newsletter

HMB Brochure - Download Our Info
Click for the BBB Business Review of this Hospital & Medical Equipment & Supplies in Fort Lauderdale FL