EN ISO 1644 Clean Rooms and Related Controlled Environments

Developed by the International Organization for Standardization (ISO) and later published as a European standard within the scope of harmonization efforts, the “ISO 14644 Clean rooms and related controlled environments” standard consists of the following sub-sections published under the same title:

• The standard “EN ISO 14644-1 Part 1: Classification of air cleanliness according to particle concentration” includes the classification of air cleanliness in cleanrooms and clean areas in terms of the concentration of particles in the air and the separation devices defined in the ISO 14644-7 standard.

For classification purposes, only particle populations with cumulative distributions based on threshold (lower limit) particle sizes ranging from 0,1 µm to 5 µm are considered.

Determining the concentration of airborne particles of specified dimensions or larger at specified sampling points relies on the use of light scattering (discrete) airborne particle counters.

The EN ISO 14644-1 standard does not provide for the classification of particle populations outside the specified lower threshold particle size range (0,1 µm to 5 µm). Concentrations of ultrafine particles (particles smaller than 0,1 µm) are addressed in a separate standard for determining air cleanliness with nanoscale particles. An M identifier can be used to quantify macroparticle populations (particles larger than 5 µm) (Annex C).

This standard cannot be used to characterize the physical, chemical, radiological, biological, or other properties of airborne particles.

• The standard “EN ISO 14644-2 Part 2: Finished Compresses” describes physical and chemical test methods for evaluating finished nonwoven compresses. This standard specifies minimum requirements for a monitoring plan in cleanrooms or clean areas. It helps demonstrate that the facility maintains the required level of air cleanliness over time, particularly in terms of airborne particle concentration.

This standard is based on the following:

• Risk assessment regarding the intended use of the cleanroom.
• Parameters that directly measure or influence the levels of particles in the air.
• The standard “EN ISO 14644-3 Part 3: Test methods” describes test methods that support operations to ensure cleanrooms and clean zones meet air cleanliness classification, other cleanliness characteristics, and relevant controlled conditions.

Performance tests were specified for two types of cleanrooms and clean zones—those with unidirectional airflow and those with non-unidirectional airflow—in three possible use cases (under construction, standby, and operational).

This standard provides test methods, recommended test equipment, and test procedures for determining performance parameters. Where the test method is affected by the type of cleanroom or clean zone, alternative procedures are suggested.

• The EN ISO 14644-4 Part 4: Design, construction and commissioning standard details the cleanroom design process, from requirements to design, construction and commissioning. This standard applies to new, refurbished and modified cleanroom installations. It does not prescribe specific technological or contractual methods for meeting these requirements.

This standard is designed for use by users, specifiers, designers, buyers, suppliers, builders, and performance verifiers of cleanroom installations. The primary cleanliness consideration is airborne particulate matter concentration. Requirements provide detailed checklists for design, construction, and commissioning. These include key performance parameters to consider. Energy management design approaches are defined to support an energy-efficient cleanroom design. Construction guidance is provided, including commissioning and verification requirements. A key element of this standard is the consideration of aspects, including maintenance, that will help ensure the consistently satisfactory operation of the cleanroom throughout its entire lifecycle.

• The EN ISO 14644-5 Part 5: Operations standard describes the requirements for establishing an operational control program to ensure efficient cleanroom operation within the specified cleanliness levels. The operational control program includes personnel management, personnel and material entry and exit, cleaning, maintenance, and monitoring. This standard specifies operational requirements related to:
• Providing a system that defines policies and operational procedures for maintaining cleanliness levels.
• Staff education
• Transportation, installation, and maintenance of stationary equipment.
• Entry and exit of materials and portable equipment into and out of the cleanroom.
• Maintaining a staff management program that includes a dress code.
• Maintaining a cleaning program that focuses on specialized cleaning.
• Maintaining the cleanroom maintenance program.
• Establishing a suitable monitoring program.

This standard provides additional information for the following:

• Staff management
• Dressing
• Training:
• Cleaning

This standard does not specifically address biocontamination control. For details on this topic, please refer to ISO 14698-1 and ISO 14698-2 standards.

• The standard “EN ISO 14644-7 Part 7: Isolation devices (clean air hoods, glove boxes, isolators and mini-environments)” describes the minimum requirements for the design, construction, installation, testing and approval of isolation devices, where they differ from the cleanroom standards described in ISO 14644-4 and 14644-5. The application of this standard takes into account the following limitations:
• User requirements are as agreed upon by the customer and supplier.
• Application-specific requirements have not been addressed.
• No specific processes to consider when installing the isolation device have been outlined.
• Fire, safety, and other regulatory issues have not been addressed specifically; where applicable, national and local regulations apply.
• The standard “EN ISO 14644-8 Part 8: Assessment of air cleanliness by chemical concentration method” outlines typical assessment processes for determining the rating levels of air chemical cleanliness in cleanrooms and related controlled environments, in terms of the concentrations of specific chemical substances (individual, group or category) in the air, and provides a protocol including test methods, analyses and time-weighted factors for their determination. This standard currently only considers concentrations of air chemical pollutants between 100 g/m3 and 10-12 g/m3 under cleanroom operating conditions.

This standard is not applicable to industries, processes, or manufacturing processes where airborne chemical substances do not pose a risk to the product or process. The purpose of this standard is not to define the nature of airborne chemical pollutants. This standard does not provide a classification of surface chemical pollution.

• The standard “EN ISO 14644-9 Part 9: Assessment of surface cleanliness with respect to particle concentration” describes a procedure for assessing the particle cleanliness levels on solid surfaces in cleanrooms and related controlled environment applications. Recommendations for test and measurement methods and information on surface properties are included in the annexes to this standard (Annexes A to D).

This standard applies to all solid surfaces in cleanrooms and associated controlled environments, such as walls, ceilings, floors, work environments, tools, equipment, and products. The procedure for evaluating surface cleanliness by particle concentration is limited to particles between 0,05 µm and 500 µm.

• The standard “EN ISO 14644-10 Part 10: Assessment of surface cleanliness with respect to chemical contamination” describes appropriate test procedures for determining the cleanliness of surfaces in cleanrooms in terms of the presence of chemical compounds or elements (including molecules, ions, atoms, and particles). This standard applies to all solid surfaces (such as walls, ceilings, floors, work surfaces, tools, equipment, and devices) in cleanrooms and related controlled environments.

For the purposes of this standard, only the chemical properties of a single particle have been considered. The physical properties of the particle have not been considered, and this standard does not cover the interaction between contaminant and the surface.

• The standard “EN ISO 14644-12 Part 12: Specifications for monitoring air cleanliness by nanoparticle concentration” covers the monitoring of air cleanliness in terms of the concentration of nanoscale particles present in the air. For monitoring purposes, only particle populations with a size limit of 0,1 microns or smaller are considered. The monitoring described here is primarily intended for use in operational situations.

In conclusion, the characteristics of monitoring air cleanliness in a cleanroom in operational conditions, specifically regarding nanoscale particle concentration, also take into account the equipment used, personnel behavior, and similar process characteristics.

• The standard “EN ISO 14644-13 Part 13: Cleaning of surfaces to achieve defined levels of cleanliness according to particle and chemical classifications” describes guidelines for achieving a certain degree of cleanliness on cleanroom surfaces, cleanroom equipment surfaces, and cleanroom material surfaces. All surfaces of interest (external or internal) are considered. This standard provides guidance on evaluating cleaning methods to achieve the required surface cleanliness according to particle concentration and chemical concentration classes, and on which techniques should be considered to reach these specified levels.

The suitability of cleaning techniques refers to the cleaning classes and related test methods found in ISO 14644-9 and ISO 14644-10 standards.

• The standard “EN ISO 14644-14 Part 14: Assessment of equipment suitability for use according to airborne particle concentration” describes a procedure for assessing the suitability of equipment (e.g., machinery, measuring equipment, process equipment, components, and instruments) for use in cleanrooms and related controlled environments in terms of airborne particle cleanliness, as specified in ISO 14644-1. Particle sizes range from 0,1 µm to 5 µm or larger (as given in ISO 14644-1).
• The standard “EN ISO 14644-15 Part 15: Assessment of the suitability of equipment and materials for use according to the concentration of chemicals in the air” describes the requirements and guidelines for assessing the cleanliness of equipment and materials intended for use in cleanrooms and related controlled environments against airborne chemicals. This standard is based on ISO 14644-8 for cleanliness classes according to chemical concentration.
• The standard “EN ISO 14644-16 Part 16: Energy efficiency in cleanrooms and separating devices” provides guidance and recommendations for optimizing energy use and maintaining energy efficiency in new and existing cleanrooms, clean zones, and separating devices. This standard provides guidance for the design, construction, commissioning, and operation of cleanrooms.

This standard covers all the features specific to cleanrooms and can be used in different fields to optimize energy use in electronics, aerospace, nuclear, pharmaceutical, hospital, medical device, food industries and other clean air applications.

• The standard “EN ISO 14644-17 Part 17: Applications of particle deposition rate” provides guidance on interpreting and applying the results of particle deposition rate measurements on one or more sensitive surfaces in a cleanroom as part of a contamination control program. This standard offers some guidance on how to influence particle deposition rate and how to reduce the risk of particle contamination on sensitive surfaces.

This standard provides information on how a cleanroom user can use particle deposition rate measurements to determine achievable limits for macroparticles on sensitive surfaces. It also presents a risk assessment methodology for determining an acceptable risk of particle deposition on sensitive surfaces in a cleanroom, and methods that can be used to reduce the particle deposition rate when this is not possible.

• The standard “EN ISO 14644-18 Part 18: Assessment of the conformity of consumables” provides guidance for assessing the appropriate use of personal and non-personal consumables in cleanrooms, clean areas, or controlled areas, based on product and process requirements, cleanliness characteristics, and functional performance characteristics. The cleanliness characteristics considered are particles or chemicals in the air or on surfaces. Biological contamination (living particles, microorganisms, or pyrogens) is considered a specific characteristic of consumables. Identification of associated risks is taken into account.

This standard complements the cleanroom operation specified in the ISO 14644-5 standard.

This standard provides guidance on the following:

• In general, determining the cleanroom suitability of consumables.
• Specifying the customer's requirements for the intended use of a consumable in terms of functional performance, cleaning properties, and special characteristics.
• Specifications by the supplier regarding the intended use of a consumable.
• Evaluating a consumable for proper use.
• Documentation
• The standard “EN ISO 14644-19 Part 19: General technical requirements for modular isolation units for emergency medical use” describes the requirements and definitions, technical requirements, inspection and testing, marking, packaging, transport and storage requirements for emergency medical modular isolation units. This document applies to modular isolation units intended for emergency medical use.

However, this standard has been discontinued.

• The standard “EN ISO 14644-21 Part 21: Airborne particle sampling techniques” addresses the physical limitations of probe and particle counter placement and the tubing connecting them, particularly for obtaining representative samples when examining particles of 5 micrometers and larger.

This standard also defines key factors for sampling performance during classification and tracing, and good practices for identifying and maintaining an acceptable compromise between achievable accuracy in counting and the applicability of counting in real-life situations.

For many years, our organization, with its competent and experienced staff, has been understanding the needs of its clients, providing the advanced testing services they require, and assisting them in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services in accordance with the EN ISO 1644 standard.