How to Score the Best Cleaning Method for Your Medical Device

In the highly controlled medical device manufacturing industry, selecting the most effective cleaning process ensures product quality, safety, and regulatory compliance. While cost considerations are important, manufacturers must take a comprehensive approach that encompasses cleaning efficiency, safety, sustainability, regulatory adherence, and long-term affordability. One effective strategy is using a cleaning scorecard to help in making informed decisions.

The role of the cleaning scorecard

A cleaning scorecard is a strategic tool that evaluates the entire parts cleaning process, focusing on the total cost per part cleaned, including direct and indirect costs. It helps manufacturers choose the most practical cleaning solution by comparing different methods across key criteria, ensuring decisions are based on a complete understanding of both the process and costs, not just upfront expenses.

Evaluating cleaning methods

Choosing the correct cleaning method requires understanding the specifics of every option available. Two primary methods used in medical device cleaning are aqueous cleaning and vapor degreasing, each with distinct advantages and challenges.

Aqueous cleaning: Aqueous cleaning uses water and chemical additives to achieve high cleanliness levels. It excels at removing inorganic, polar contaminants like rust, tarnish, heat scale, and smuts. It is particularly effective on simple-shaped parts without crevices where water might get trapped and cause corrosion. Aqueous cleaning can also incorporate rust-preventative coatings or brighteners, saving processing time.

However, the method often requires significant water and energy resources. The process involves multiple washing and rinsing stages, high-temperature inputs, and extensive drying, leading to higher energy consumption and a larger carbon footprint. Additionally, processing the used water for recycling and addressing water scarcity in some regions pose sustainability challenges.

Vapor degreasing is an efficient cleaning method using low boiling temperature solvents to clean and dry parts in a single cycle. Graphic courtesy of MicroCare.

Vapor degreasing: Vapor degreasing is an efficient cleaning method using low boiling temperature solvents to clean and dry parts in a single cycle, reducing power consumption. It effectively removes non-polar, organic soils like machine oils, grease, and baked-on resins. The fluid is continuously recycled, enhancing its environmental footprint.

However, it is crucial to choose cleaning fluids that follow environmental regulations and are sustainable long-term. Environmental regulations significantly influence the selection process. Responsible manufacturers must select methods and fluids that meet current and future regulations.

Calculating capital and operating costs

When evaluating cleaning methods, it's important to consider one-time capital costs and ongoing operating expenses. Capital costs include the purchase price of the capital equipment, site preparation, and any necessary facility upgrades. Operating costs encompass direct materials, labor, and manufacturing overheads.

Cleaning throughput — the rate at which parts are cleaned — is another key factor in determining operational efficiency and cost-effectiveness. It involves evaluating the number of parts cleaned per hour, factoring in loading and unloading times, and considering the total surface area of parts if they vary in shape and size. Larger vapor degreasers typically offer faster, more efficient cleaning for high-volume operations, while smaller benchtop machines may be more suitable for lower-volume needs.

Considering labor and maintenance costs

Labor costs can significantly affect the overall cost of a cleaning process. Automated systems reduce labor expenses, but it's essential to account for any non-automated tasks that may arise, such as added inspections or re-cleaning. Maintenance costs, including routine checks and replacement of consumables, should also be factored into the total cost analysis.

Ensuring consistent and reliable cleaning is crucial for maintaining high-quality standards in medical device manufacturing. The chosen method must effectively remove contaminants without damaging the parts. Vapor degreasing, for instance, provides a consistent automated cleaning process that can be closely monitored, ensuring uniform cleanliness and reducing variability in cleaning outcomes.

Testing and validation

Before choosing the cleaning method, it is advisable to evaluate the equipment with contaminated parts. Manufacturers should compile detailed reports on the cleaning process, including fluids used, temperatures, times, and results, to verify that the system meets specific cleaning requirements. This validation step is crucial to ensure the selected method performs effectively in real-world conditions.

Final scoring and decision making

After thorough testing, the last step is to score each cleaning method based on a comprehensive set of criteria:

By converting all cost data into a performance index of total cost per part cleaned, decision-makers can select the option that minimizes costs while maximizing compliance, efficiency, and consistency.

Choosing a cleaning method can have far-reaching implications in an industry where precision and quality are paramount. By adopting a systematic approach to evaluation and decision-making, manufacturers can select a cleaning process that meets their immediate needs and positions them for long-term success.

A cleaning scorecard is a strategic tool that evaluates the entire parts cleaning process, focusing on the 'total cost per part cleaned,' including direct and indirect costs. Graphic courtesy of MicroCare.

About the author:

Elizabeth Norwood is a senior chemist at MicroCare, LLC, which offers precision cleaning solutions. She has been in the industry more than 25 years and holds a bachelor’s in science in Chemistry from the University of St. Joseph. Norwood researches, develops and tests cleaning-related products. She currently has one patent issued and two pending for her work. For more information, visit www.microcare.com.