Using RVI to prevent contamination and maintain purity of pharmaceuticals 

Strict purity and contamination control of pharmaceutical manufacturing facilities is required under various international standards, such as ASME (American Society of Mechanical Engineers), AWS (American Welding Society) and local regulatory authorities such as the U.S. Food and Drug Administration.

Bacterial or foreign-particle contamination in production-line equipment can cause serious health issues for consumers and shake public confidence in the industry.

Preventing contamination in medication production lines is one of the main goals of good manufacturing practices (GMP). Following GMP is a prerequisite for the pharmaceutical industry to prevent poor quality or incorrect mixtures of elements from reaching the consumer. GMP requirements include implementing strict equipment maintenance and cleaning protocols supported by QC and QA inspections and audits, all backed by detailed documentation.

Drug manufacturers use a combination of indirect and direct quality control (QC) techniques to prevent contamination throughout the production line.

Remote visual inspection (RVI) is a practical tool that can help drug manufacturers prevent contamination and maintain product-line purity to meet GMP requirements.

This article discusses how facilities can leverage remote visual inspection (RVI) using video scopes and borescopes to reduce contamination threats. Further, it offers three ways to maintain pristine pipe welds in pharmaceutical plants using visual inspection.

Four ways video scopes can improve drug plant preventative maintenance

Video scopes and borescopes allow direct access and evaluation of hard-to-reach areas inside facilities.

Video scope insertion tubes can have an internal diameter as small as 4 mm (0.16 in.) and a length up to 30 meters (98 ft), making them ideal tools to reach often inaccessible locations inside process pipes, tubes, tanks, and vessels. With their outstanding image quality, video scopes can be used to check welds for signs of corrosion or monitor locations where microorganism colonies tend to grow.

Here are four ways manufacturing facilities can incorporate a video scope or borescope into their proactive maintenance:

1. Validating the compliance of new processing equipment. Before the initial operation of new or replacement equipment, drug production facilities can perform a baseline video scope inspection to ensure compliance to standards and regulations for welds on pipe bends, elbows, joints and tanks.

Specifically, the colors of heat-affected zones (HAZ) and surface porosity indicate the quality of the welds. Therefore, a video scope with a high-quality image processor can balance the illumination and color representation to ensure that the images demonstrate the actual weld condition based on established discoloration acceptance criteria for welds and heat-affected zones.

2. Monitoring problem areas for residue buildup. Between production batch changes, pharmaceutical plants need to thoroughly clean and inspect the processing equipment. Video scopes enable quality assurance inspectors to check key contact locations for residue buildup or corrosion and monitor potential microorganism growth areas.

3. Checking metal walls of pipes and cessels for corrosion. During periodic plant maintenance, RVI can be used to check and monitor any deterioration of processing equipment, such as corrosion or erosion.

4. Documenting inspection images to comply with good manufacturing practices. After each visual inspection, an inspection report is required for auditing and validation. All video scope inspection images or video footage can be documented as evidence. The software capabilities of borescope or video scope systems directly impact the efficiency of the report generation process. Well-designed inspection software enables a streamlined workflow.

The latest video scopes provide QA/QC inspectors in pharmaceutical manufacturing facilities with numerous features to ease processing equipment verifications and record keeping. These include the following:

• High image quality provided by advanced optics resulting from a century of expertise
• Innovative image processors that reduce noise and sharpen images for a high probability of detection (POD) in low-light and reflective environments.
• Adjustable color saturation to enhance the visibility of the weld’s heat-affected zone (HAZ).
• Interchangeable light sources in white and ultra-violet options.
• Modern “inspection assist” software for efficient image data management.
• Portable and ergonomic design for inspection in restrained spaces
• Easy-to-use user interface for simple operation.
• Stereo measurement upgrades for quantitative defect assessment.

Three ways to maintain pristine pipe welds in pharmaceutical plants using visual inspection

Weld quality control and assurance (QA/QC) is critical in drug manufacturing facilities. Yet, it’s one of the biggest challenges, given that process pipes can have thousands of welds and joints in inaccessible locations. If even one of those welds is deficient, corrosion, leaks, or contamination can occur.

Both automated and manual welds on stainless steel processing pipes can be a challenge to inspect. Methods such as ultrasonic and X-ray testing are commonly used to identify internal flaws and defects within the volume of a weld and on the parent material. However, after the welding and heat-treatment processes, inspectors need to visually examine the weld’s inner diameter (ID) and the weld root. Because of restricted access, remote visual inspection is a viable, non-destructive solution.

Video scopes and borescopes help ensure all pipework and welds are fit-for-purpose and comply with welding codes and industry standards. Here are three ways to incorporate video scopes into pharmaceutical process pipeline inspection:

1. After equipment installation, repair work or expansion

Before initial operation of equipment or during plant expansion or repair work, QA inspectors can use RVI equipment to check all welded parts that require validation:

• Internal diameter (ID) surface finish
• Defects in the root section of the weld (i.e., root undercut, incomplete root penetration, burn through, etc.)
• Heat-affected zone (HAZ) near the weld (i.e., color differences as per ASME BPE 2016)
• Geometrical mismatch between welded pipe such as excess weld metal, weld overlap, etc.

It’s essential to have RVI equipment with features that ensure a thorough inspection of welds in the complicated process piping network. Ideal features include:

• Insertion tubes of various diameters (starting at 4 mm) and lengths (up to 30 meters), offering direct viewing access to inspect weld roots and IDs of complex geometry and extensive networks of stainless steel pipes.
• Markings (numbers) on the pipes to identify the location of each weld. Such numbers can be used for the corresponding recorded inspection video and images.
• An optional UV light source that can be used in combination with penetrant testing to identify surfaces defects that are invisible and undetected with white light.

Wide-angle view optical adaptors, such as a 220° direct view lens tip, allow a complete profile view of the weld ID, increasing the inspection efficiency and speed without compromising the probability of detection (POD). The 220° adaptor shows a complete view of the condition of both the front and backside of the weld.

2. After batch-to-batch cleaning and product-to-product changeover

Welds and the surfaces inside process pipelines must not disrupt the flow of products passing through them. If the product becomes lodged, it can either spoil or contaminate products flowing through later. Welds, elbows and joints in pipes are key problem zones for residue buildup.

After maintenance personnel have cleaned the equipment between batch or product changes, RVI is recommended to check for residue to avoid cross-contamination in these inaccessible problem zones. In addition, inspectors can use the video scope or borescope to verify the cleanliness of all welds that are in areas in contact with the flow of the product. Regional regulators, such as the FDA, typically recommend these inspections.

Ways to Ease Residue and Buildup Checks

When checking for residue around welds, elbows and joints, there are a couple video scope/borescope features that help make the job easier:

• For a quick yet thorough inspection, using a wide-angle optical adaptor provides a complete panoramic view inside the pipe for viewing any medication remnants directly on the video scope screen.

• Halation caused by highly reflective surfaces, such as stainless steel pipes, can impede video scope or borescope inspection. Operators usually need to manually adjust the illumination brightness to see properly. Some video scopes are equipped with features to resolve this problem:
  • Processors that interact with the illumination system, actively adjusting the brightness level for the operator to deliver an optimized image that is clear and sharp.
  • Image processing technology supports a wide dynamic range, maintaining visibility in dark areas even when the brightness is decreased to avoid halation.
• Some video scopes offer scope tip articulation to allow fast navigation and precise control (joystick or touchscreen) to the target – through complex pipe networks, tight corners and restricted spaces.
• Other newer video scopes offer software for user-friendly inspection data management.

3. Periodic inspection for corrosion and structural integrity

Pharmaceutical production facilities are not immune to corrosion and other structural integrity problems. As a result, process water that passes through the pipes is periodically monitored to check the content of impurities. The cause of this contamination can include microorganisms that nestle around pitting corrosion and proliferate in biological residue in processing equipment.

To ensure the hygienic soundness of process pipelines, it is a good practice to implement video scopes or borescopes to inspect all welds and inaccessible locations as part of regular preventative maintenance.

Ultraviolet light reveals microorganisms

Colonies of microorganisms are challenging to locate with white light. Therefore, borescopes or video scopes that offer a UV light source option help detect microorganisms in processing pipes, vessels or tanks because the UV light source exposes this organic material through its fluorescence.

Checklist for video scope or borescope inspections in pharmaceutical manufacturing plants

Here is a summary of my tips for inspecting stainless steel pipes or other process equipment:

• Choose the correct length and diameter insertion tube for your application. Video scopes and borescopes with various lengths and diameter insertion tubes are available.
• Select the suitable optical tip adaptor for your application needs. I recommend a 220° “fish-eye” lens for a fast, efficient inspection with a high POD.
• Maintain proper hygiene during and after inspection—wipe down the video scope insertion tube with isopropyl alcohol (IPA) before and after use to remove contaminants.
• Inspecting weld integrity. Ensure the white balance is correctly set before use. Observing with accurate color representation is crucial to detect discoloration in the HAZ to validate that it meets the acceptance criteria.
• Adjust the light source’s brightness to reduce halation inside shiny stainless steel pipes, tanks, and vessels. Consider video scopes that have dynamically adjusting light sources that do that for you.
• Thoroughly inspect the welded section of pipes by rotating the insertion tube with a side view adaptor. For large-diameter pipes, use a centering device to support placing the insertion tube at the center of the pipe.
• Thoroughly record and document your inspection. Record still images and videos of entire weld inspections as evidence for quality control validation and audits.

Remote visual inspection (RVI) is a practical tool that can help pharmaceutical manufacturers prevent contamination and maintain product-line purity to meet GMP requirements. Newer video scopes and borescopes offer features that help perform thorough, reliable inspections, especially in hard-to-access areas such as welds, where problems often originate but can go unseen until it’s too late.

Hafees Fraisada is product marketing manager for Olympus in the EMEA region. He has more than 15 years’ experience in the medical and industrial industries. Based in Hamburg, Germany, Fraisada is a member of Olympus’ remote visual inspection (RVI) team. His background is in science, and he has a master’s in international business administration.