Understand the Air Particle Counter in Pharmaceutical Equipment

Air particle counters are crucial for the environmental integrity of global pharmaceutical, biopharmaceutical, and radiopharmaceutical facilities. As the pharmaceutical industry becomes increasingly globalized, collaboration and coordination are becoming more common, driving the need for continuous monitoring of these facilities and the reliance on digital solutions to meet your contamination control requirements. This article will explore the importance of air particle counters, their types, and their key role in maintaining cleanroom environments.

There are mainly three forms of airborne particle counters: handheld, portable, and fixed remote (online). This article will focus on the portable and fixed particle counters.

The portable dust particle counter is a standalone device equipped with a user-friendly control interface. It features an integrated sampling system, making it easy to carry and use flexibly. Users can set sampling parameters, collect data, and transfer the data to external systems via WiFi or a secure network. To prevent contamination, the air sampling system must be equipped with an exhaust system that includes a high-efficiency air filter.

Portable particle counters can be powered by an internal battery or an AC power supply, and they offer a variety of sampling flow rates:

• 28.3L/min (standard flow rate) portable particle counter: The sampling flow rate is 1.0 CFM (28.3 LPM), which is suitable for general cleanroom operations.

• 100L/min (high flow rate) portable particle counter: The sampling flow rate exceeds 1.0 CFM (28.3 LPM), which is particularly useful in cleanroom certification testing. For example, devices with a sampling flow rate of 100L/min or higher are especially valuable in Class A environments because they can significantly reduce sampling time when sampling large particles of 3μm and above.

Compared to portable particle counters, fixed remote particle counters are smaller in size, easier to install in confined spaces, and more reliable and durable. They can be mounted on process equipment, cleanroom walls, or transportation devices. They typically operate at a flow rate of 0.1 CFM (2.83 LPM) or 1.0 CFM (28.3 LPM) for data logging or real-time data transmission to external systems, such as Facility Monitoring Systems (FMS).

Fixed remote (online) dust particle counters can be divided into two types: those with a built-in pump and those without a built-in pump.

• Remote particle counters with a built-in pump: These have an integrated sampling system and exhaust filtration device. Although they are larger in size, noisier, and more expensive than their pumpless counterparts, they do not require an additional vacuum pump or distribution system. However, they require regular filter replacement and pump maintenance.

• Remote particle counters without a pump: These rely on an external vacuum source, making them smaller, quieter, and less expensive. With no built-in filter or small pump, they also have lower maintenance costs. However, the facility's vacuum system needs to be regularly maintained to ensure proper flow, and it is recommended to have a redundant vacuum system to ensure continuous operation.

When installing and using particle counters in pharmaceutical facilities, it is crucial to clearly distinguish between cleanroom classification and operational process monitoring.
• Cleanroom Classification: Commonly also referred to as cleanroom validation or certification, this is the formal process of testing the environment according to the ISO 14644-1 standard. It includes determining sampling locations, specifying sampling volumes, and meeting additional certification requirements, such as monitoring particles of 0.5 micrometers and 5.0 micrometers in size. Cleanroom classification provides confidence that the environmental air quality meets the specific cleanliness standards of a particular classification, essentially verifying whether the cleanroom has achieved its design criteria

.• Operational Process Environmental Monitoring: This is a continuous monitoring process used to track critical locations during high-risk operations in the production of sterile products. It includes alarm and notification systems that can alert personnel in real-time when the environment approaches or exceeds operational limits.Key areas that typically require continuous monitoring include sterile products, containers, and closures that are exposed to the risk of contamination. These high-risk operations are usually conducted under Grade A conditions, associated with unidirectional airflow environments. This type of monitoring is essentially intended to verify whether the cleanroom is operating in a controlled state.

Particle counters used in pharmaceutical facilities must meet specific requirements for design, reliability, durability, and calibration:
• Rational Design: The design of particle counters should not interfere with the environment they are monitoring. They need to withstand cleaning and disinfection processes and be chemically compatible with cleaning agents. Additionally, particle counters should feature ergonomic design, be lightweight, and easy to carry. Long battery life is also an important characteristic to ensure business continuity.

• Reliability and Durability: The construction of particle counters should ensure their durability, especially considering the limited lifespan of laser diodes, which are common components in these devices.

• Performance and Calibration: Particle counters must be calibrated in accordance with the ISO 21501-4 standard, covering calibration aspects such as particle size, flow rate, size resolution, counting efficiency, false count rate, and voltage limits.In addition, particle counters should also be capable of verifying particle counting data and be designed to ensure data integrity.

Different countries may have different recommended practices or requirements for air particle counters. For example, Japan has JIS B 9921, and China has JJF 1190-2008, both of which specify detailed calibration requirements. The United States has ASTM F50-129 and IEST-RP-C0148, while the United Kingdom refers to the PHSS Technical Monograph No. 16 as a guideline. However, ISO 14644-1:2015 is an internationally recognized standard that every particle counter should support.

Selecting a suitable particle monitoring system for controlled environments requires a comprehensive consideration of many factors:
• Product Type: The type of products being produced, due to their specific hazards or environmental requirements, may influence the choice of monitoring equipment.
• Sterilization Method: Clarifying whether the product undergoes terminal sterilization or is filled aseptically will help design the corresponding monitoring system.
• Cleanroom Classification: Determining the cleanroom classification that needs to be monitored will decide the number of monitoring points and operational restrictions.
• Target Country: Different countries may have different regulations, which will affect the overall system design
.• Equipment Usage: Understanding the production equipment in use can identify key monitoring locations.
• Remote APC Type: The decision to use a remote APC with a built-in pump depends on facility limitations and considerations for placement location.
• Monitoring Locations: Determine monitoring locations based on risk assessment and past monitoring data, rather than relying solely on the grid pattern of ISO 14644-1
.• Connection Methods: Options include Ethernet, WiFi, or API for connectivity.
• Data Export: Digitize data export through CIF, network, or WiFi.

Therefor, Air particle counters are essential pieces of equipment in global pharmaceutical, biopharmaceutical, and radiopharmaceutical facilities. They play a crucial role in maintaining the environmental integrity required to produce safe and effective pharmaceutical products. Familiarity with the types of air particle counters, their roles in cleanroom classification and process monitoring, and the various considerations when selecting these devices is vital to ensuring regulatory compliance and product quality.