IEST Technical Guides serve as complementary documents to ISO Standards ISO 14644, Cleanrooms and associated controlled environments – Part 1: Classification of air cleanliness, and ISO 14644, Cleanrooms and associated controlled environments – Part 2: Specifications for testing and monitoring to prove continued compliance with ISO 14644-1.

Working Group 101 of the IEST Contamination Control Division (WG-CC101), Forum on Air Cleanliness Technology, has developed the following four Technical Guides to be used as supplements to the ISO 14644 Cleanroom Standards:

IEST-G-CC1001: Counting Airborne Particles for Classification and Monitoring of Cleanrooms and Clean Zones
Technical Guide 1001 launches the series of Guides, with general coverage of methods for sampling air in clean environments using a discrete-particle counter (DPC) to determine concentrations of airborne particles. The protocols presented are applicable for any cleanroom occupancy state and apply to classification (in accordance with ISO 14644-1), as well as monitoring (in accordance with ISO 14644-2). Several terms specific to counting procedures are defined. This document also provides detailed setup procedures to complement the concise provisions of section B.4.3 of ISO 14644-1. A sample format is provided for systematic data reporting in conjunction with ISO 14644-1 and ISO 14644-2.

First printing, 1999

IEST-G-CC1002: Determination of the Concentration of Airborne Ultrafine Particles
Technical Guide 1002 supplements the coverage of procedures for determining the concentration of ultrafine particles as provided by ISO 14644-1. Procedures presented in this Guide are suitable for classification (in accordance with ISO 14644-1) and monitoring (in accordance with ISO 14644-2) of cleanroom and clean zone environments that would typically qualify as ISO Class 4 or cleaner. The specified concentration or the measured concentration of ultrafine particles (expressed in terms of ultrafine particles per cubic meter) is referred to by its numerical values as the U descriptor. Ultrafine particles in this usage fall within the range of size distribution having a lower limit (threshold) particle size smaller than 0.1 μm. (This definition of ultrafine particle size represents a departure from the concept used in Federal Standard 209E.) This Guide describes the apparatus and procedures necessary for determining the U descriptor and provides guidelines and an example format for reporting data.

First printing, 1999

IEST-G-CC1003: Measurement of Airborne Macroparticles (Electronic and Print Versions Available)
 Technical Guide 1003 covers the realm of macroparticles, the particles of concern with respect to operations involving the “other end” of the controlled environment spectrum. The size range for macroparticles (a term coined for ISO 14644-1) includes particles larger than 5 μm in diameter. Particles in this size range are most commonly of interest for classification and monitoring in cleanrooms and clean zones having air cleanliness classifications that would generally qualify as ISO Class 5 or less clean. The air cleanliness is expressed in terms of the M descriptor, the numerical value of the concentration of macroparticles per cubic meter. The M descriptor may be used to describe either the specified concentration or the measured concentration of macroparticles. This Guide contains descriptions of apparatus and procedures for classification (in accordance with ISO 14644-1) and monitoring (in accordance with ISO 14644-2) of clean environments requiring control of airborne contaminants in the macroparticle size range.

First printing, 1999

IEST-G-CC1004: Sequential-Sampling Plan for use in Classification of the Particulate Cleanliness of Air in Cleanrooms and Clean Zones (Electronic and Print Versions Available)
Technical Guide 1004 expands the coverage of sequential sampling introduced in ISO 14644-1. By applying sequential sampling procedures in lieu of standard sampling procedures, significant savings of sampling time, perhaps as much as 80 percent, can be achieved when classifying the cleanliness of very clean air in cleanrooms and clean zones. The procedure is most appropriate for environments having air cleanliness that qualifies as ISO Class 4 or cleaner when tested in accordance with ISO 14644-1.

First printing, 1999