Cleanrooms are essential to any manufacturing process where particulate contamination can affect the quality of goods produced. Cleanrooms provide secure environments with controlled air filtration, lowering the possibility of product contamination or large particulate interference with critical process manufacturing. Cleanrooms are used in industries such as medical device manufacturing, food processing, computer manufacturing and server holding, military and aerospace research and life sciences as well as thousands of other potential applications.
Cleanroom Industry Requirements & Classifications
Cleanroom standards are classified according to the number and size of particles permitted per volume of air in a specific amount of time. Clean Air Products engineers can provide guidelines for the class of cleanroom required. Typically, businesses and organizations are aware of their cleanroom performance requirements because of customer, industry or government specification. For example, government regulation USP 797 outlines specific requirements for pharmaceutical product manufacturing.
Clean room industry requirements are classified according to ISO 14644-5:2004 which specifies basic requirements for cleanroom operations. Federal Standard 209E is still also used (see Table 1).
ISO cleanroom classifications are rated according to how much particulate of specific sizes exist per cubic meter (see second chart). The "cleanest" cleanroom is a class 1 and the "dirtiest" a class 9. Each clean room is rated by ISO class. This cleanroom standard rating system provides the necessary information to make an informed decision based on your product needs. Most clean rooms fall into the class 6,7, or 8 categories.
Cleanroom Industry Requirement Standards
A cleanroom’s performance requirements identify the cleanroom class level required at a given state or condition. There are three level of condition (states) for testing and characterizing the performance of cleanrooms: as-built; at rest; and operational. Specific test methods for these three classifications are outlined in 14644-3:2005.
Most cleanrooms are rated and sold in the as-built category—an empty room with the filter system running, but without workers and production equipment. However, adding workers and equipment will introduce contamination and affect the room rating. A clean room may be rated ISO 6 at rest, but at ISO 7 during operation (see Table 1). To comply with performance requirements, the as-built empty room should be tested and benchmarked, followed by testing and documentation of the at-rest and operational states. If contamination in the at-rest or operational states is not in compliance, corrective steps need to be taken. These steps can range from examining the production process and number of workers in the cleanroom, to testing the room’s air flow performance.
In addition, cleanroom air flow performance can be cost-effectively upgraded by adding fan filter modules (FFM). For example, FFMs cover approximately 5-15% of an ISO 8 Class cleanroom ceiling. Upgrading to an ISO 7 cleanroom requires 15-25% ceiling coverage and covering 25-40% of the ceiling changes the room to an ISO 6 Class.
ISO Class 1
The “cleanest” cleanroom is ISO 1, used in industries such as life sciences and electronics that require nanotechnology or ultra-fine particulate processing. The recommended air changes per hour for an ISO class 1 clean room is 500-750, and the ceiling coverage should be 80–100%.
ISO Class 2
The recommended clean room air changes per hour for an ISO class 2 rated cleanroom is 500-700, with a ceiling coverage of 80-100%.
ISO Class 3
The recommended clean room air changes per hour for an ISO class 3 rated cleanroom is 500-750, with a ceiling coverage of 60-100%.
ISO Class 4
The recommended clean room air changes per hour for an ISO class 4 rated cleanroom is 400-750, with a ceiling coverage of 50-90%.
ISO Class 5
The recommended clean room air changes per hour for an ISO class 5 rated cleanroom is 240-600, with a ceiling coverage of 35-70%.
ISO Class 6
The recommended clean room air changes per hour for an ISO class 6 rated cleanroom is 150-240, with a ceiling coverage of 25-40%.
ISO Class 7
The recommended clean room air changes per hour for an ISO class 7 rated cleanroom is 60-150, with a ceiling coverage of 15-25%.
ISO Class 8
The recommended clean room air changes per hour for an ISO class 8 rated cleanroom is 5-60, with a ceiling coverage of 5-15%.
Determining the correct cleanroom standards for a new product or business requires balancing many aspects – from process requirements and cost, to performance and construction. Clean Air Products staff members work hands-on with you to review the basics of selection, and all applicable clean room industry requirements. Clean Air Products provides cleanrooms by ISO class, as well as additional cleanroom accessories to guarantee superior air quality and particle filtering.
