ISO 29462:2022 粒子サイズと気流に対する抵抗による現場での除去効率に関する一般的な換気ろ過装置とシステムの実地試験 | ページ 6

3.1.1

air filter bypass

proportion of the challenge air stream that passes around an air cleaner without interacting with the air cleaner (test device)

[SOURCE:ISO 29464:2017; 3.1.3, modified — The preferred terms"bypass" and"sneakage" have been deleted and"(test device)" has been added.]

3.1.2

air velocity

rate of air movement at the test device

Note 1 to entry: It is expressed in m/s (ft/min) to three significant figures.

[SOURCE:ISO 29464:2017, 3.1.2, modified — “at the test device” has been added to clarify the location,"fpm" has been changed to"ft/min".]

3.1.3

allowable measurable concentration of the particle counter

fifty percent of the maximum measurable concentration as stated by the manufacturer of the particle counter (3.1.12)

[SOURCE:ISO 29464:2017, 3.2.115]

3.1.4

coefficient of variation

C_V

standard deviation of a group of measurements divided by the mean

[SOURCE:ISO 29464:2017, 3.2.31]

3.1.5

coincidence error

error which occurs because at a given time more than one particle is contained in the measurement volume of a particle counter (3.1.12)

Note 1 to entry: The coincidence error leads to a measured number concentration which is too low and a value for the particle diameter which is too high.

[SOURCE:ISO 29464:2017, 3.2.32]

3.1.6

diluter

dilution system

system for reducing the sampled concentration to avoid coincidence error (3.1.5) in the particle counter (3.1.12)

[SOURCE:ISO 29464:2017, 3.2.46]

3.1.7

filter efficiency

fraction or percentage of a challenge contaminant that is removed by a test device

[SOURCE:ISO 29464:2017, 3.1.12, modified — The preferred term"efficiency" has been deleted.]

3.1.8

filter installation

filtration devices and systems such as a single filter or a group of filters mounted together with the same inlet and outlet of air

[SOURCE:ISO 29464:2017, 3.2.85]

3.1.9

general ventilation

process of moving air from outside the space, recirculated air, or a combination of these into or about a space or removing it from the space

[SOURCE:ISO 29464:2017, 3.2.100]

3.1.10

isoaxial sampling

sampling in which the flow in the sampler inlet is moving in the same direction as the flow being sampled

[SOURCE:ISO 29464:2017, 3.2.104]

3.1.11

isokinetic sampling

technique for air sampling such that the probe inlet air velocity (3.1.2) is the same as the velocity of the air surrounding the sampling point

[SOURCE:ISO 29464:2017, 3.2.105]

3.1.12

particle counter

device for detecting and counting numbers of discrete airborne particles present in a sample of air

[SOURCE:ISO 29464:2017, 3.2.114]

3.1.13

particle size range

defined particle counter (3.1.12) channel

[SOURCE:ISO 29464:2017, 3.2.137]

3.1.14

reference filter

dry media-type filter that has been laboratory tested for removal efficiency by particle size (3.1.15)

3.1.15

removal efficiency by particle size

removal efficiency

ratio of the number of particles retained by the filter to the number of particles measured upstream of the filter for a given particle-size range

[SOURCE:ISO 29464:2017, 3.2.149, modified — The preferred term"removal efficiency" has been added.]

3.1.16

resistance to airflow

difference in absolute (static) pressure between two points in a system

Note 1 to entry: Resistance to airflow is measured in Pa.

[SOURCE:ISO 29464:2017, 3.1.36, modified — The preferred terms"differential pressure","pressure differential" and"pressure drop" have been deleted.]

3.1.17

system efficiency

removal efficiency (3.1.15) of a filter system where upstream and downstream particle count measurements may be across several filter banks or other system components

[SOURCE:ISO 29464:2017, 3.2.163]

3.1.18

HEPA filter

filters with performance complying with requirements of filter class ISO 35H to ISO 45H as per ISO 29463-1

[SOURCE:ISO 29464:2017, 3.2.84]