ISO 14644-1 terms and definitions

Question 1

cleanroom (general- 3.1.1)

Answer 1

room within which the number concentration of airborne particles is controlled and classified, and which is designed, constructed, and operated in a manner to control the introduction, generation, and retention of particles inside the room.

Question 2

clean zone (general- 3.1.2)

Answer 2

defined space within which the number concentration of airborne particles is controlled and classified, and which is constructed and operated in a manner to control the introduction, generation, and retention of contaminants inside the space.

Question 3

installation (general- 3.1.3)

Answer 3

cleanroom or one or more clean zones, together with all associated structures, air-treatment systems, services, and utilities

Question 4

classification (general- 3.1.4)

Answer 4

method of assessing level of cleanliness against a specification for a cleanroom or clean zone
** levels expressed in terms of ISO class, which represents maximum allowable concentrations of particles in a unit volume of air.

Question 5

particle (airborne particles- 3.2.1)

Answer 5

minute piece of matter with defined physical boundaries

Question 6

particle size (airborne particles- 3.2.2)

Answer 6

diameter of a sphere that produces a response, by a given particle-sizing instrument, that is equivalent to the response produced by the particle being measured

Question 7

particle concentration (airborne particles- 3.2.3)

Answer 7

number of individual particles per unit volume of air

Question 8

particle size distribution (airborne particles- 3.2.4)

Answer 8

cumulative distribution of particles concentration as a function of particle size

Question 9

macroparticle (airborne particles- 3.2.5)

Answer 9

particle with an equivalent diameter >5 microns

Question 10

M descriptor (airborne particles- 3.2.6)

Answer 10

designation for measure or specified concentration of macroparticles per cubic meter of air, expressed in terms of the equivalent diameter that is characteristic of the measurement method used.
**can be regarded as upper limit for the averages at sampling locations. M descriptors cannot be used to define ISO classes, but may be quoted independently or along with ISO classes

Question 11

unidirectional air flow (airborne particles- 3.2.7)

Answer 11

controlled airflow through the entire cross-section of a cleanroom or a clean zone with a steady velocity and airstreams that are considered to be parallel

Question 12

non-unidirectional air flow (airborne particles- 3.2.8)

Answer 12

air distribution where the supply air entering the cleanroom or clean zone mixes with the internal air by means of induction

Question 13

as-built (occupancy states- 3.3.1)

Answer 13

condition where the cleanroom or clean zone is complete with all services connected and functioning but with no equipment, furniture, materials, or personnel present

Question 14

at-rest (occupancy states- 3.3.2)

Answer 14

condition where the cleanroom or clean zone is complete with equipment installed and operating in a manner agreed upon, but with no personnel present

Question 15

operational (occupancy states- 3.3.3)

Answer 15

agreed condition where the cleanroom or clean zone is functioning in the specified manner, with equipment operating and with the specified number of personnel present

Question 16

resolution (testing instrumentation- 3.4.1)

Answer 16

smallest change in a quantity being measured that causes a perceptible change in the corresponding indication

Question 17

maximum permissible measurement error (testing instrumentation- 3.4.2)

Answer 17

extreme value of measurement error, with respect to a known reference quantity value, permitted by specifications or regulations for a given measurement, measuring instrument, or measuring system

Question 18

LSAPC light scattering airborne particle counter
light scattering discrete airborne particle counter
(instrument specifications- 3.5.1)

Answer 18

instrument capable of counting and sizing single airborne particles and reporting size data in terms of equivalent optical diameter

Question 19

discrete-macroparticle counter (instrument specifications- 3.5.2)

Answer 19

instrument capable of counting and sizing single airborne macroparticles

Question 20

time-of-flight particle sizing apparatus (instrument specifications- 3.5.3)

Answer 20

discrete-particle counting and sizing apparatus that defines the aerodynamic diameter of particles by measuring the time for a particle to accommodate to a change in air velocity