Full text of US Federal Standard F5209E (Clean Room Standard)

FS 209E and lSO 14644 CleanRoom Classification StandardsIntroduction

of FS 209E and lSO 14644-1 and -2Airborne Particulate

Cleanliness Class ComparisonAirbore Particulate Cleanliness ClassesRequired TestingOptional Testing

The History and Future of lSO Cleanroom Standards

ISO Cleanroom Standards

ISO TC 209 Working Groups

Introduction

Federal Standard 209E has long been the only definition of cleanroom classification levels available from a standardsorganization. f$209E, Airborne Particulate Cleanliness Classes in Clean Rooms and Clean Zones, is from the U.s.General Service Administration and approved for use by all U.s, agencies. In the absence of an international standard FS 209E was broadly used internationally.

The need for a new international standard that covered more cleanroom environmental parameters and practices ledto the formation of a technical committee of the International Standards Organization. The technical committee isnamed, ironically, Tc 209 Cleanrooms and Associated Controlled Environments. The goal of Tc 209 is "standardizationof equipment, faclities, and operational methods for cleanrooms and associated controlled environments, Thisincludes procedural limits, operational limits and testing procedures to achieve desired attrilbutes to minimize microcontamination.

This lSO committee will producedocuments that relate to cleanrooms or clean zones (described0 ne stancarg sbelow). The first two standards have been published: ISO 14644-1 and -2. The first document, ISO 14644-1, Cleanrooms and associated controlled environments.

Part 1: Classification of airborne particulates has been releasedas a final draft international standard (fDlS). The second document, lSO 14644-2, Cleanrooms and associatedcontrolled environments.

Part 2: Testing and monitoring to prove continued compliance with ISO14644-1: has beenreleased as a draft international standard (DlS), Both are legal for use in trade.By U.s. law, FS 209E can be superseded by new international standards. lt is expected that 209E will be in use in someindustries through the next five years, but that eventually it will be replaced globally by iso 14644-1.The actual text of the standards must be ordered from the appropriate standards organization (see Sources and links).This paper gives a generaloverview of the reguired particle count measurements given in the standards.

Return to contents

of FS 209E and lSO 14644-1 and -2

The cleanliness classification levels defined by Fs209E and lSO 14644-1 are approximately equal, except the new lSO standard uses new class designations, a metric measure of air volume and adds three additional classes - two cleanerthan Class 10 and one beyond than Class 100,000. The second new ISO standard, iso 14644-2, gives requirements formonitoring a cleanroom or clean zone to provide evidence of its continued compliance with lSO 14644-1.The following table compares FED STD 209E to the new lSO 14644-1 classifications.

Airborne Particulate Cleanliness Class Comparison

The ISO standard also requires fewer sample locations, especially as the cleanroom/area size increases; however, the ISO standard does require minimum one minute samples, whereas the Federal Standard allows shorter samples,especially at smaller particle sizes.

For example, to certify an fs Class 10 cleanroom (lS0 class 4), with 250 square feet (7.08 square meters), classified at 0.3 micron with a 1 cf/m flow rate particle counter, the required number of sample locations, sample volumes, andsample times would be as follows:

FS209E requires 10 sample locations, 19.6 liter minimum sample volume (0.85 cf), and a sample time of 51 seconds.This yields a total minimum sample time of 510 seconds and 10 equipment moves.ISO 14644-1 requires 5 sample locations, 19.6 liter minimum sample volume (0.85 cf ), but also a minimum sampletime of one minute yielding three samples of one cubic foot, This yields a total sample time of 180 seconds and threeequipment moves.

The precise count levels reguired by lSO 14644-1 for each classification, by particle size, are given below.

Airborne Particulate Cleanliness Classes (by cubic meter)

ISO 14644-2 determines the type and frequency of testing reguired to conform with the standard. The following tables indicate which tests are mandatory and which tests are optional.

Required Testing (lSO 14644-2)

Optional Testing (lSO 14644-2)

Return to contents

The History and Future of lSO Cleanroom Standards

In 1992, at the urging of the Institute of Environmental Sciences, the American National Standards institute petitionedISO to create a technical committee on cleanrooms and associated controlled environments, This new committee, lSOTC 209, was formally established in May 1993. lts mission is to develop an international standard for cleanrooms andassociated controlled environments that encompasses the standardization of equipment, facilities, and operationalmethods, while also defining procedural and operational limits and testing procedures to minimize contamination.Thirty-four countries are currently active in lSO Tc 209. Voting members are Australia, Belgium, China, DenmarkFinland, France, Germany, ltaly, Jamaica, japan, Korea, The Netherlands, Norway, Portugal, Russia, Sweden, Switzerlandthe United Kingdom, and the United States. Nonvoting members are Bulgaria, the Czech Republic, Egypt, indiaIreland, Malaysia, New Zealand, the philippines, Poland, Saudi Arabia, South Africa, Thailand, Turkey, Ukraine, andYugoslavia.

Two Draft international Standards (DlS) have been released by the committee: ISO/DlS 14644-1.

Cleanrooms andassociated controlled environments-Part 1: Classification of airborne particulates, and lSO/Dls 14644-2 Cleanroomsand associated controlled environments-Part 2: Specifications for testing and monitoring to prove continuedcompliance with ISO 14644-1. These first is cleanroom standards are two of 10 documents (see table A) that willmake up the new family of global cleanroom standards, Many of these documents are at the final voting stage and canbe legally used in trade.

ISO Ceanroom standards

ISO/FDIS 14644-1 Classification of Air Cleanliness

This document covers the classification of air cleanliness in

cleanrooms and associated controlled environments.Classification in accordance with this standard is specified and accomplished exclusively in terms of concentration ofairborne particles.

ISO/DlS 14644-2 Cleanroom Testing for Compliance

This document specifies requirements for periodic testing of a cleanroom or clean zone to prove its continuedcompliance with ISO 14644-1 for the designated classification of airborne particulate cleanliness. These requirements invoke the test described in ISO 14644-1 for the classification of the cleanroom or clean zone. Additional tests are alsospecified, to be carried out based on the reguirements of this International Standard. Optional tests, to be applied atthe user's discretion, are also identified.

ISO-14644-3 Methods for Evaluating & Measuring Cleanrooms & Associated Controlled EnvironmentsThis document descrilbes the necessary performance tests for various types of cleanrooms. The occupancy states of "asbuilt", "at rest", and "in operation" are defined as well as appropriate levels of certification. A large index is providedon a wariety of test methods and appropriate equipment.

ISO-14644-4 Cleanroom Design & Construction.This document will be a primer on the design and construction of cleanrooms. lt will cover all aspects of the process from design development to startup and commissioning.

ISO-14644-5 Cleanroom OperationsThis document will be a primer on cleanroom operation. lt will cover all aspects of the operation of a cleanroom including entry and exit procedures for equipment and personnel, education and training, cleanroom apparel, andfacility issues such as maintenance, housekeeping, monitoring, system failure, etc.

ISO-14644-6 Terms, Definitions & Units

This document will provide a consistent reference for all terms, definitions and units discussed across all lSOcleanroom standards.

ISO-14644-7 Enhanced Clean Devices

This document will focus on specialized stand-alone clean spaces including their design, construction, and operations.

ISO-14644-8 Molecular ContaminationThis will be a new document covering measurement of airborne molecular contamination in clean zones. The firstmeeting is scheduled for December 1998.

ISO-14698-1 Biocontamination: Control General PrinciplesThis document describes principles and basic methodology for a formal system to assess and controlbiocontamination where cleanroom technology is applied.

ISO-14698-2 Biocontamination: Evaluation & Interpretation of Data

This document describes basic principles and methodology for microbiological data evaluation. lt provides a methodof estimating of biocontamination from sampling for viable particles in zones at risk,ISO-14698-3 Biocontamination: Methodology for Measuring Efficiency of Cleaning inert SurfacesThis document outlines the methodology to measure the effectiveness of cleaning and/or disinfection of inert surfaceshaving biocontaminated wet soiling or biofilms.

ISO TC 209 Working Groups

Listed below are lSO TC 209's seven working groups and their missions.

Working Group 1 

ISO14644-1, "Classification of Air Cleanliness" Three new classes have been added to the existing standard, federalStandard 209, two cleaner and one dirtier.

ISO 14644-2 covers specifications for testing and monitoring. This document specifies the reguirements formonitoring a cleanroom or clean zone to provide evidence of its continued compliance with lSO 14644-1 for thedesignated classification of airborne particulate cleanliness, A schedule of normative and informative tests is included

in the document.

Working Group 2

ISO 14698-1, "Biocontamination Control General Principles". This document describes the principles and basicmethodology for a formal system to assess and control biocontamination, lt willinclude the general reguirements of asampling plan; target, alert, and action levels; qualification; and reporting.ISO 14698-2, "Evaluation and Interpretation of Biocontamination Data." This document describes the basic principlesand methodological reguirements for all microbiolocical data evaluation and the estimation of biocontamination dataobtained from sampling for viable particles. lt will also include evaluation of the initial monitoring plan and of the dataresulting from routine monitoring, as well as analysis of the data, trending, and record keeping.

Working Group 3

A working group on metrology and testing methods. Performance tests are specified at operational phases-as-builtat-rest, and operational. The items to be measured are categorized as either primary or user-optional tests. Primarytests include particle count, airflow velocity, airlow volume, pressure differential, and installed filter leakage. User.optional tests include flow visualization, airflow parallelism, airflow turbulence, temperature, humidity, moleculecontamination, electrostatic charge, particle fallout, recovery, and integrity.

Working Group 4

iso 14644-4, "Design and Construction," This document specifies reguirements for the design and construction ofcleanroom and clean ar devices, as well as requirements for start-up and qualification. lt also provides guidance on the basic elements of design and construction.

Working Group 5A cleanroom operations working group. Topics to be addressed include entry/admittance, procedures, and cleaning,as well as maintenance as it relates to equipment, materials, and people.

Working Group 6

In detailing terms, definitions, and units, the definitive document of this working group must include all definitionsfrom all approved documents of lSO Tc 209. Consequently, it will be the final lSO Tc 209 document.

Working Group 7

The Enhanced Clean Devices working group.