26 Aug Cleanroom Particle Counting: A Quick Primer
Though too small to see with the human eye, a single 0.5 micron particle can cause malfunctions to products in industries like semiconductors and aerospace. And just because we can’t see them, doesn’t mean they aren’t there, which is why particle counting has become so important. In this article, we’ll cover what cleanroom particle counting is, why it’s so important, the instruments used to measure particles, and more.
What is Cleanroom Particle Counting?
Particle counting is the process of measuring and monitoring the number of airborne particles within a cleanroom. These particles can be anything from dust and pollen (non-viable particles) to microorganisms (viable particles); generally, it is their presence or abundance that leads to the contamination of products and the disruption of important processes.
Such particle counting helps ensure that the cleanrooms meet their required standards, such as those set by ISO 14644 or FDA. These standards define the maximum particle sizes and limits allowable, which of course makes it important to regularly monitor particle counts.
Why is Particle Counting Important in Cleanrooms?
As we touched on already, particle counting is important for two main reasons. First and foremost, by measuring particle counts, companies can prevent the quality of products or processes from being harmed and disrupted. Second, reaching proper particle levels is important to meeting regulations, especially for ISO 14644.
To illustrate, let’s take a look at how counting particles may be important in the pharmaceutical industry. When manufacturing drugs, it’s important that the final product be sterile. Airborne particles can carry microorganisms that contaminate medications, and this can lead to expensive product recalls or even harm to patients. As a result, particle counting has become an essential part of the manufacturing process.
Let’s take a look at a few more industries to see how particles can hurt products/processes.
The Impact of Particulate Contamination
As we demonstrated with pharmaceuticals, contamination can have severe consequences for different industries. Here are a few more sectors that can be adversely affected:
- Semiconductors: Particles can cause defects in microchips, leading to device failure. (As a result, semiconductor manufacturing environments see some of the strictest particle control measures taken. A single particle can cause real damage to parts.)
- Medical Devices: Contaminated devices can result in malfunction or infection when used by patients. Medical devices placed in the body need to be manufactured in strictly controlled environments.
- Aerospace: Contaminants in sensitive equipment, such as GPS systems, can lead to failure, which poses risks to safety and mission success.
Consequences of Non-Compliance
Furthermore, failing to keep proper particle counts in cleanrooms can lead to serious consequences. In the United States, regulatory bodies such as the FDA may take legal action resulting in fines, shutdowns, product recalls, and loss of consumer trust. Regular particle counting helps prevent these issues.
What Instruments are Used in Cleanroom Particle Counting?
- Handheld Particle Counters: These particle counters are compact, lightweight, and easy to use. They are specifically designed for on-the-spot checks and for more localized measuring.
- Remote Particle Counters: These ones installed inside cleanrooms so that particle levels can be continuously monitored. They are typically connected to a central system.
- Portable Particle Counters: Portable particle counters are larger than handheld models, but are still mobile. They may have handles or wheels. These counters are equipped with more advanced features, allowing them to monitor larger areas and provide more detailed data.
How Do You Set Up and Conduct Particle Counting Procedures?
Perhaps the most important aspect of particle counting procedures is making sure the conditions allow for accurate and reliable data. Though real-world procedures may differ depending on the industry and application, we have put together a short step-by-step guide to how one might measure particles in a cleanroom.
- Calibrate Your Instruments: Before you begin, make sure that all particle counters have been properly calibrated according to the manufacturer’s instructions. It goes without saying that calibration is fundamental to accurate measurements.
- Prepare the Cleanroom: Make sure the cleanroom is operating under normal conditions during particle counting. This includes running HVAC systems and other equipment that might affect air quality. The goal is to obtain the most accurate data possible while the cleanroom is in full operation.
- Position the Particle Counter: Place the counter at locations specified in your cleanroom’s monitoring plan. Typically, this includes areas near workstations, entrances, air returns, and critical areas.
- Conduct the Count: Follow the specific instructions for your particle counter, making sure you take measurements for the recommended length of time to get an accurate sample.
- Record the Data: After completing the count, document the results, noting the time, location, and any environmental factors that could have influenced the result.
Please keep in mind that this is just a basic guide, and your exact procedure may differ from ours. Another thing to note when taking measurements is not to disturb the airflow, as this can introduce more particles and skew the results.
Cleanroom Particle Counting: The Bottom Line
As we’ve said already, cleanroom particle counting is necessary both to comply with regulations and ensure that cleanrooms are working as they should. As a result, particle counting is a necessary step in protecting the products and processes that are handled in cleanrooms. Whether you’re in pharmaceuticals, semiconductors, or another industry that relies on cleanrooms, you will need to effectively carry out particle counting in order to achieve operational success.
FAQs About Cleanroom Particle Counting
1. How often should particle counting be performed in a cleanroom?
The frequency depends on the ISO cleanroom classification as well as industry requirements, but regular monitoring, often daily or weekly, is usually recommended.
2. How do environmental factors affect particle counting accuracy?
Certain environmental factors, such as airflow, temperature, and humidity can change particle distribution in areas where you’re measuring particles. As a result, when conducting a particle count, you should always try to make the conditions the same as when the cleanroom is in full operation.
3. Do automated systems replace the need for manual particle counting in cleanrooms?
Automated systems allow for continuous monitoring and real-time data, but they may not entirely replace manual checks in all situations. This is because particle counts are often location dependent. Sometimes, you need to measure exact/critical spaces, and that will require manual particle counting.
4. What are the consequences of inaccurate particle counting in a cleanroom?
Inaccurate counts can lead to non-compliance with standards, product contamination, regulatory fines, damage to a company’s reputation, and even shutdowns.