How to Tell If Your Glove Port Interface Has a Leak

Glove ports are an essential tool for working with sensitive and potent materials.

These interfaces make it possible for operators to perform crucial work within contained environments such as isolators and restricted access barrier systems (RABS) without breaking containment. However, they are also prone to damage, which can lead to contamination.

An undetected leak in the glove interface can compromise the sterility of precious biopharmaceuticals, not to mention bring production to a halt while the leak is addressed. In the case of radiopharmaceuticals or other potent materials, glove leaks also put operators at risk for radiation exposure.

Because a small hole can cause significant problems, operators must be trained to identify and address leaks in the glove port interface. Each facility will have its own detection protocols that must be followed, but there are several best practices that operators should be familiar with to prevent, detect and correct glove port interface leaks.

Visual Inspection of the Glove Interface

In general, operators should perform visual checks before and after using the glove port. Pay close attention to the hand and fingertips of the gloves, as this is where most punctures and tears occur. Even if the glove is intact, discoloration and crazing can indicate that its structural integrity is breaking down.

If operators notice a hole or other abnormalities in the glove, it should be replaced immediately in accordance with the facility’s glove replacement protocol. Failure to detect and correct a puncture can cause irreparable damage to sensitive biologics in addition to production delays and regulatory issues.

Pressure Differential Monitoring

Typically, isolators employ air handling systems that maintain a specific pressure differential. Operators should keep a close eye on the pressure differential and the operation of air handling systems, as anomalies may indicate a breach in containment.

If the air handling system is working harder to maintain internal pressure, it may be due to a leak. Similarly, an unexplained drop in pressure suggests a possible leak.

Because breaches of containment are most common at the glove port interface, operators should inspect the glove port components to ensure they are intact before proceeding to additional troubleshooting.

Glove Leak Testers

If a leak is suspected, operators may employ a glove leak tester. These devices dock to one (or more) glove ports in an isolator or RABS and run a test to determine if there is a breach.

Leak testers come in a variety of form factors and typically use the principles established by the positive pressure decay method to detect leaks.

When selecting a glove leak tester, the following factors should be considered:

• Compliance with cGAMP specifications
• Compatibility with your specific glove port size and shape
• Glove cycle testing time
• Ergonomics and ease of use
• Data collection and storage capabilities

Special Considerations for Radiopharmaceuticals

Radiopharmaceuticals require additional precautions to ensure the safety of operators.

Often, operators will put on one or two pairs of disposable gloves before inserting their hand into the glove of the isolator as an extra layer of protection. Once the operator’s hands are removed, the disposable gloves should be checked for radiation. If there has been any radiation exposure, this signals a possible leak at the glove interface.

Environmental monitors can also be placed outside of the isolator to alert personnel to radiation.

Glove Port Leak Prevention

While visual inspection, pressure monitoring and leak testers can help identify when a containment breach has occurred, there are several commonsense steps that operators can take to prevent leaks from happening in the first place.

First, facilities should establish regular schedules for glove replacement. Glove change schedules should be dictated by the application, the number of batches processed with each glove and the duration of glove use. Glove changes should always be documented with batch details.

Training is also essential for preventing glove port leaks. Ultimately, each facility will have its own set of standard operating procedures (SOPs) for glove port operation and leak detection, which operators should review regularly. In particular, operators should understand the correct way to clean glove interfaces, as improper cleaning can cause gloves and seals to fail prematurely. In addition, operators must be trained on emergency breach protocols and glove changes.

Finally, glove ports that are not in use for extended periods should be covered with plug assemblies. These are more durable than gloves, providing a more secure seal that deters leaks.

The integrity of a glove port system is crucial for efficient, scalable and safe biopharma production. For best results, operators must recognize the signs of a leak and follow best practices to prevent leaks effectively.