What is an ISO class 8 cleanroom?

An ISO 8 Cleanroom is a controlled environment that adheres to the ISO 14644-1 standard for cleanliness, which is used in industries where the control of particulate contamination is critical, such as in pharmaceuticals, Electronics, biotechnology, and food production. ISO 8 cleanrooms are less stringent than ISO5 or 6 cleanrooms but still provide a controlled environment for specific applications.

What is an ISO 8 Cleanroom?

An ISO 8 cleanroom limits airborne particles (≥0.5 microns) to 3,520,000 per cubic meter. Used in industries like pharmaceuticals and electronics, it offers moderate contamination control, balancing cleanliness with cost-effectiveness compared to higher ISO classes.

1. Air Filtration: ISO 8 cleanrooms use HEPA filters (High-Efficiency Particulate Air Filters) to trap particles and keep the air clean. These filters can capture particles as small as 0.3 microns with a high efficiency (at least 99.97%).

2. Airflow and Air Changes: The cleanroom's airflow is carefully managed to ensure that the particles are constantly moved out of the room. ISO 8 cleanrooms typically require around 20-60 air changes per hour (ACH). The airflow is typically unidirectional, meaning that air flows in a single direction to minimize turbulence and particle re-suspension.

3. Applications: ISO 8 cleanrooms are used in industries where contamination control is important but not as critical as in higher classes. Common applications include electronics assembly, packaging of pharmaceuticals, and biotech research. These rooms also serve industries that require clean but non-sterile environments, such as food manufacturing or medical device assembly.

4. Personnel and Protocols：Personnel working in ISO 8 cleanrooms are required to follow gowning procedures to prevent contamination from human particles, such as skin flakes and hair. While the gowning protocol may not be as strict as in lower-class rooms, it still involves wearing cleanroom attire such as lab coats, gloves, and hair covers.

What Does ISO 8 Mean?

ISO 8 cleanrooms are used when the contamination risk is moderate, and higher levels of cleanliness are not required. Industries such as electronics, pharmaceuticals, and food production often use ISO 8 cleanrooms because they strike a balance between maintaining Clean air and being cost-effective. 

What is the Difference Between ISO 7 and ISO 8?

How Many Air Changes Per Hour for ISO8?

1. Standard Requirement

ISO 8 cleanrooms typically require 20-60 air changes per hour (ACH). The specific number of air changes depends on the requirements of the application, the level of contamination control required, and the size of the cleanroom.

2. Why Air Changes Matter

Air changes per hour determine how frequently the air in the room is replaced with clean, filtered air. A higher air change rate improves particle removal and ensures that the room's air quality stays within the specified limits. For an ISO 8 cleanroom, 20 air changes per hour may be sufficient for moderate contamination control, but more sensitive operations might require up to 60 ACH.

3. Energy Considerations

While higher air change rates improve cleanliness, they also increase energy consumption. Maintaining the necessary airflow and pressure for 20-60 ACH requires an efficient HVAC system, but the energy cost can be significant, especially for larger cleanrooms. 

What is the Acceptable Air Changes Per Hour?

Influencing Factors: The number of air changes required depends on the process being performed and the cleanliness level needed. More sensitive processes, such as pharmaceutical production or electronic component assembly, may require a higher ACH to maintain particle control. However, higher air change rates can also lead to increased energy consumption and higher operational costs.

Energy Efficiency: Achieving the required ACH while maintaining energy efficiency is critical. Cleanrooms must balance effective filtration with optimal airflow to minimize the energy demand of the HVAC system. An efficient HVAC system that is well-maintained can help meet ACH requirements without excessive energy costs.

Regulatory Compliance：For compliance with ISO Standards, cleanrooms must maintain the required air changes and particle limits. Regular testing of air quality and filtration systems ensures that cleanrooms meet the necessary standards and help maintain compliance with regulations.

What is 20 Air Changes Per Hour?

1. Air Change Rate: 20 air changes per hour refers to the replacement of the entire volume of air in a room 20 times every hour. This is suitable for environments where moderate contamination control is required, such as in ISO 8 cleanrooms.

2. Impact on Contamination: A 20 ACH rate ensures that airborne particles are effectively filtered and removed, helping to maintain the room's cleanliness level. It is sufficient for less stringent cleanroom environments, like those found in food processing or general pharmaceutical industries.

3. Energy Implications: Maintaining 20 ACH can help optimize the balance between cleanliness and energy consumption. It’s a common requirement for cleanrooms where cost and energy efficiency are important considerations.

How to Calculate Room Air Changes Per Hour?

To calculate air changes per hour (ACH), use the following formula:

Where:

• Airflow is the rate at which air is supplied or extracted (in cubic feet per minute (cfm) or cubic meters per hour (m³/hr)).

• Room Volume is the total volume of the room (in cubic feet (cf) or cubic meters (m³)).

For example, if A CleanRoom has an airflow of 6,000 cfm and a room volume of 12,000 cubic feet.

The ACH would be:

This calculation ensures that the room meets the necessary airflow requirements for the desired cleanliness standard.