Glossary
Essential terms and definitions for cleanroom technology.
Products
Particle Counter
An instrument that detects and counts particles in the air or a liquid. It is used to monitor cleanroom contamination levels.
Airborne Particle Counter (APC)
A particle counter designed to measure suspended particles in air. It is widely used for cleanroom classification, validation, and routine monitoring.
Handheld Particle Counter
A portable particle counter used for quick spot checks, troubleshooting, and mobile cleanroom measurements.
Benchtop Particle Counter
A stationary particle counter typically used in labs or cleanroom monitoring stations, often offering higher flow rates and faster measurements than handheld units.
Online Particle Counter
A particle counter used for continuous or near-real-time monitoring, commonly installed at fixed points in cleanrooms and connected to monitoring software.
LSAPC
An abbreviation often used for Laser Sampling Airborne Particle Counter, referring to laser-based instruments used to count airborne particles in cleanroom monitoring.
Remote Particle Monitoring System
A system that connects multiple particle counters/sensors to central software for real-time monitoring, alarming, trending, and compliance reporting.
Microbial Air Sampler
An instrument that collects airborne microorganisms onto culture media (such as agar plates) to assess microbiological contamination in clean environments.
Airflow Meter
An instrument used to measure air velocity or airflow volume, commonly used for HVAC verification and cleanroom airflow balancing.
Smoke Generator
A device that produces visible smoke/aerosol to visualize airflow patterns, support airflow studies, and assist in HVAC troubleshooting and cleanroom validation.
HEPA Filter Leak Test
A test procedure to verify the integrity of HEPA/ULPA filters and their installation by challenging with aerosol and scanning for leaks.
Aerosol Photometer
An instrument that measures aerosol concentration, commonly used in HEPA/ULPA filter leak testing together with a challenge aerosol.
Multipoint Sampler
A device that sequentially switches sampling between multiple locations/ports, allowing one particle counter to monitor multiple points.
General
Cleanroom
A controlled environment where the concentration of airborne particles is controlled to specified limits.
Particle Size Channel
A measurement channel that reports particle counts above a specified size threshold (for example ≥0.5 µm or ≥5.0 µm).
Sampling Flow Rate
The volume of air drawn through an instrument per unit time (for example 28.3 L/min). It affects sampling representativeness and time-to-result.
Alarm Limit (Threshold)
A predefined limit that triggers an alarm when particle counts or other parameters exceed the set value.
Data Logging
The recording and storage of measurement results (such as particle counts, timestamps, and locations) for analysis, traceability, and compliance.
Calibration
A process of verifying and adjusting an instrument against traceable standards to ensure measurement accuracy and compliance.
Impaction Sampling
A microbial sampling method where air is directed through a head/nozzle and particles impact onto an agar surface for incubation and colony counting.
Standards
Components
HEPA Filter
High Efficiency Particulate Air filter, capable of removing at least 99.97% of dust, pollen, mold, bacteria, and any airborne particles with a size of 0.3 microns (µm).
Agar Plate
A culture medium plate used to grow microorganisms collected during environmental monitoring, enabling CFU counting after incubation.
PAO Aerosol
A commonly used challenge aerosol for HEPA/ULPA filter leak testing. The photometer measures concentration upstream and downstream to detect leaks.
Isokinetic Probe
A sampling probe designed to match the air velocity at the sampling point, reducing sampling bias and improving measurement representativeness.
Sampling Manifold
A manifold or valve block that distributes or switches sampling flow among multiple sampling lines, often used in multipoint monitoring setups.
Pressure Relief Valve
A safety component that releases pressure when it exceeds a set limit, helping protect systems and maintain stable operation.