Isolation and Containment

“How do I check for leaks in an isolator? Can I patch a flexible isolator front/isolator flexible film canopy or should it be replaced?”

These are common isolator questions that we’ve heard and ones that many people are probably curious to know more about.

We asked Frank Razzaboni, President of Park Bioservices, a designer and manufacturer of flexible front isolators/gloveboxes, surgical isolators, HEPA-filtered transport containers, and other biomedical equipment, to provide a few thoughts in response to these questions.

How do I check for leaks in an isolator??
Outlined below are two acceptable methods for checking leaks in an isolator; the first requires no special tools.

1. The isolator blower should be on positive pressure.
2. Next, the exhaust port should be blocked.
3. The blower is turned on and should be allowed to fully pressurize the isolator. You will recognize the full inflation because the arms should straighten out and the front/canopy will become quite firm.
4. Seal off the intake by closing the ball valve or blocking the intake port.
5. In a standard 32 oz/750 ml spray bottle, mix a small amount (5 ml) of dish detergent with tap water.
6. Spray liberally around any potential leak points.
7. Check for bubbles at:

a. gloves and arms, particularly where the sleeves meet the canopy, finger tips, and the webbing between the fingers
b. the frame that holds the flexible front onto a semi-rigid isolator
c. any couplings for inlet and outlets

This second method requires a helium cylinder with a regulator and a specialized device that detects helium (Leak Seeker Q196).

1. The isolator blower should be on positive pressure.
2. Next, the exhaust port should be blocked.
3. Then the blower should be turned on and allowed to partially pressurize the isolator. You will recognize the partial inflation because the arms should be limp (bent at about where the elbows are located) and the front/canopy will be soft to the touch.
4. Helium is slowly introduced into the intake until the glove arms are fully inflated. Caution must be observed not to over pressurize the isolator and cause stress damage.
5. Seal off the intake by closing the ball valve or blocking the intake port.
6. Using the wand on the detector, slowly scan all the surfaces mentioned below:

a. gloves and arms, particularly where sleeves meets the canopy, finger tips, and the webbing between the fingers
b. the frame that holds the flexible front onto a semi-rigid isolator
c. any seams in either the soft or hard plastic components
d. doors and ports
e. any couplings for inlet and outlets and or hoses

Both methods should give satisfactory results. The helium test is useful in situations where the soapy water has failed to find a leak.