ISO clean room design

ISO Clean room design

1. Design Considerations

The design of an ISO clean room must prioritize airflow, filtration, and surface materials. The layout should minimize contamination risks, typically employing a unidirectional airflow pattern. The clean room should include high-efficiency particulate air (HEPA) filters, capable of trapping 99.97% of particles ≥0.3 micrometers, to maintain air quality.

2. Material Selection

Materials used in clean room construction must be non-porous and easy to clean. For example, walls and ceilings are often made from stainless steel or painted gypsum board. Flooring should be smooth and chemically resistant, with vinyl or epoxy options commonly used to reduce particle generation and facilitate cleaning.

3. HVAC Systems

Heating, ventilation, and air conditioning (HVAC) systems are crucial in clean room design. According to ISO 14644-3, airflow rates must be determined based on the clean room’s classification. An ISO 5 clean room typically requires an airflow rate of 0.45 meters per second to ensure effective particle removal and uniform distribution.

4. Validation and Certification

To ensure compliance with ISO standards, clean rooms must undergo validation and certification processes. This includes initial tests for particle counts, airflow patterns, and pressure differentials. Regular re-certification, typically every six months, is recommended to maintain compliance and operational integrity.

Relevant Standards and Regulations

• iso 14644-1: This standard provides the classification of air cleanliness in clean rooms and controlled environments, detailing the permissible particle concentrations for various cleanroom classes.

• iso 14644-2: This standard outlines the monitoring and control of cleanroom environments, specifying requirements for measuring airborne particulate contamination and establishing a regular monitoring schedule.

• ISO 14644-3: This standard focuses on the test methods for clean rooms, including procedures for determining the cleanliness of the air and the performance of the clean room.

• ISO 14698-1: This standard addresses the evaluation and control of microbial contamination in cleanrooms, providing guidelines to ensure the microbial quality of the environment.

• ISO 14698-2: This part of the ISO 14698 series specifies the requirements for monitoring and controlling microbial contamination, offering details on sampling methods and analysis.

• ISO 9001: Although not specific to cleanrooms, this quality management standard emphasizes continuous improvement and customer satisfaction, relevant for cleanroom operations in regulated industries.

• Good Manufacturing Practice (GMP): These guidelines ensure that products are consistently produced and controlled according to quality standards, applicable in pharmaceutical and biotechnological cleanroom environments.

• Federal Standard 209E: Though now obsolete, this standard was widely used in the U.S. and provides historical context for CleanRoom Classifications prior to the adoption of ISO standards.

What is the ISO Scale for Cleanroom?

Definition of ISO Scale

The ISO scale for cleanrooms categorizes environments based on air cleanliness. It defines maximum allowable particle concentrations, ensuring that controlled environments meet specific cleanliness standards to protect sensitive processes.

Classification System

The classification ranges from ISO1, the cleanest, allowing only 10 particles ≥0.1 micrometers per cubic meter, to ISO Class 9, which permits 35,200,000 particles. Each class has strict requirements for particle limits.

ISO Cleanliness Specification

Particle Concentration Limits

ISO cleanliness specifications outline permissible particle counts in cleanrooms. For example, ISO5 allows no more than 3,520 particles ≥0.5 micrometers per cubic meter, ensuring a controlled environment for sensitive operations.

Air Quality Requirements

The specifications also dictate air quality parameters, including humidity and temperature levels. Maintaining these conditions is essential for worker safety and product quality, particularly in industries that require sterile environments.

Monitoring Standards

Regular monitoring and testing are required to maintain ISO cleanliness specifications. This includes routine particle counting and environmental assessments to ensure compliance with established cleanliness standards and operational integrity.

How Much ISO is Acceptable?

1. ISOStandards: Acceptable ISO classifications depend on the industry and specific applications. For critical processes, ISO5 or lower is often required, while less sensitive operations may allow ISO7 or 8 environments.

2. Regulatory Compliance: Acceptance of ISO classifications is also influenced by regulatory requirements. Industries such as pharmaceuticals and biotechnology often necessitate stringent adherence to lower ISO classes to comply with Good Manufacturing Practices (GMP).

3. Risk Assessment: Determining acceptable ISO levels involves risk assessment. Companies must evaluate potential contamination risks and adjust their cleanroom classifications accordingly to ensure product safety and quality.

Requirements for ISO 5 Clean room

• Airborne Particulate Limits

ISO 5 Clean rooms must limit airborne particles to no more than 3,520 particles per cubic meter for particles ≥0.5 micrometers. This strict limit is crucial for industries requiring high levels of cleanliness.

• Airflow and Filtration

An ISO 5 clean room requires effective unidirectional airflow, typically achieved through high-efficiency particulate air (HEPA) filters. These filters must capture at least 99.97% of particles down to 0.3 micrometers, ensuring optimal air quality.

• Temperature and Humidity Control

Maintaining specific temperature and humidity levels is essential in an ISO 5 clean room. The temperature should generally be kept between 20°C and 24°C, with relative humidity levels ideally below 60% to prevent moisture-related contamination.

• Surface Materials and Design

The surfaces in an ISO 5 clean room must be non-porous and easily cleanable. Common materials include stainless steel and specialized coatings that minimize particle generation and facilitate effective cleaning protocols.

Which Cleanroom is Cleaner: ISO 3 or ISO 8?

1. Comparison of Classes

ISO 3 clean rooms are significantly cleaner than ISO 8 environments. ISO 3 permits a maximum of 1,000 particles ≥0.5 micrometers per cubic meter, whereas ISO 8 allows up to 3,520,000 particles, highlighting the vast difference in cleanliness.

2. Applications of Each Class

ISO 3 clean rooms are typically used in highly sensitive applications, such as semiconductor manufacturing and certain pharmaceutical processes. In contrast, ISO 8 environments may be suitable for less critical operations, like certain assembly tasks.

3. Compliance and Standards

Choosing between ISO 3 and ISO 8 depends on compliance requirements and the specific needs of a facility. Industries that prioritize contamination control will often opt for ISO 3 to ensure the highest level of cleanliness and product integrity.