What Is a Microbial Air Sampler?
There are several types of microbial air samplers. The most widely used system is the impaction-based air sampler on agar plates, commonly referred to as an impactor.
This system consists of two main components:
- An air pump
- A sampling headpiece containing an agar plate
The pump draws air through a perforated cover into the headpiece. The airflow changes direction above the agar surface. Due to centrifugal force, airborne particles impact the agar and adhere to it.
Microorganisms rarely travel alone; they are typically associated with dust or aerosol particles. After sampling, the agar plate is incubated. Microorganisms multiply and form visible colonies that can be counted as colony-forming units (CFU).
Based on the sampled air volume, CFU per cubic meter can be calculated.
This method is the most commonly used approach for:
- Active air sampling
- Viable particle monitoring
Advantages of Impaction on Agar
For routine microbial air quality control, this method offers significant advantages.
Common monitoring parameters include:
- Total viable count (TVC)
- Total yeasts and molds
- In most controlled environments, expected CFU ranges are known. The objective is to measure cultivable microorganisms efficiently.
- Impaction on agar provides:
- Direct sampling on plate
- Simple incubation
- Cost-effective detection
- Broad regulatory acceptance
It remains one of the most practical and economical microbiological monitoring methods across pharmaceutical, biotech, food, and environmental sectors.
EU GMP Annex 1 — Air Monitoring Requirements
EU GMP Annex 1 governs sterile production in pharmaceutical and biotechnology environments. It includes a dedicated section on:
Viable and non-viable environmental & process monitoring.
Three types of air monitoring are defined:
1. Passive Sampling (Settle Plates)
- Agar plates exposed for up to 4 hours
- Simulates real contamination conditions
- Plates incubated and colonies counted
2. Volumetric (Active) Air Sampling
- Typically performed using an impactor
- Standard: max 1000 L per plate at 100 L/min
- Continuous monitoring (e.g., 25 L/min) allows larger sampled volumes
- Provides quantitative CFU per air volume
3. Non-Viable Particle Monitoring
- Measurement of particles <0.5 µm and <5 µm
- Performed using particle counters
Threshold limits and sampling frequencies are defined for cleanroom grades A, B, C, and D. For Grade A zones, stainless steel samplers are required, often with satellite probes.
Continuous viable particle monitoring according to the new GMP Annex 1
According to GMP Annex 1 §9.24:
Continuous viable air monitoring in Grade A areas must be performed throughout critical processing, including aseptic setup and operations.
A similar risk-based approach applies to Grade B.
Monitoring must:
- Capture interventions and transient events
- Detect system deterioration
- Avoid introducing contamination risks
During extended air sampling, agar media can progressively dehydrate.
Loss of moisture reduces nutrient availability, which may:
- Inhibit microbial growth
- Lead to underestimation of CFU
- Affect data reliability
To minimize dehydration during continuous monitoring:
- Use lower flow rate air samplers (e.g., 25 L/min)
- Use Petri dishes containing ≥ 30 mL agar medium
- These measures help maintain culture integrity and ensure accurate colony counts."
Our products
Microbial air monitoring system that samples at 25l/min to comply with continuous monitoring of the new GMP Annex 1 in Grade A and B zones. Unit is constructed in stainless steel to resist H2O2 decontamination. The unit can be connected with up to 3 satellite units to sample different locations simultaneously, or program them to sample in relay. System can also be configured to do remote sampling. This air sampling system is deal for continuous monitoring.
Each PACK consists of:
- 1 TRIO.BAS RABS ISOLATOR stainless steel command unit with battery charger,
- 1 calibration certificate,
- 1 s/s satellite,
- 1 s/s aspirating head (code 830) with s/s cover head (code 465),
- 1 cable connection (5 mt) (code 265),
- 1 cable for data transfer
- and 1 robustus medium carrying case
Microbial air monitoring system that samples at 25l/min to comply with continuous monitoring of the new GMP Annex 1 in Grade A and B zones. each PACK consists of: 1 air sampler with Bluetooth and battery charger, 1 calibration certificate, 1 s/s aspirating head (code 830) with s/s cover head (code 465), 1 cable for transfer data and 1 robustus carrying case.
Microbial air monitoring system that samples at 25l/min to comply with continuous monitoring of the new GMP Annex 1 in Grade A and B zones. Unit has 2 heads to be programmed to do sampling in relay to cover a longer critical process. Each PACK consists of: 1 air sampler with Bluetooth and battery charger, 1 calibration certificate, 2 s/s aspirating head (code 830) with s/s cover head (code 465), 1 cable for transfer data and 1 robustus carrying case
Microbial air monitoring system that samples at 25l/min to comply with continuous monitoring of the new GMP Annex 1 in Grade A and B zones. Unit has 3 heads to be programmed to do sampling in relay to cover a longer critical process. Each PACK consists of: 1 air sampler with Bluetooth and battery charger, 1 calibration certificate, 3 s/s aspirating head (code 830) with s/s cover head (code 465), 1 cable for transfer data and 1 robustus carrying case.
Including:
1x TRIO.BAS MINI BLUETOOTH Air sampler (100 lts/min) Petri 90 plate with Battery charger 100/240VCA 18VDC 859 mA - cable with adapter for plug Eu/UK/USA - and 1 calibration certificate
1x s/s ASPI HEAD Petri plate
1x COVER HEAD s/s to protect ASPI HEAD
1x LIGHT STANDARD carrying case - 43x35x19h cm
Including:
1x TRIO.BAS MONO BLUETOOTH Air sampler (100 lts/min) Petri 90 plate with Battery charger 100/240VCA 18VDC 859 mA with adapter for plug Eu/UK/USA - and CABLE for transfer data and 1 calibration certificate
1x s/s ASPI HEAD Petri plate
1x COVER HEAD s/s to protect ASPI HEAD
1x ROBUSTUS STANDARD carrying case - 48x38x17h cm
Part of multiple Portable Microbial Active Air Samplers, the
TRIO.BAS™ MONO INDUCTION is a Single aspirating chamber for Petri or Contact plates with Bluetooth and base station induction charger. Suitable for users who perform a large number of controls in different environments with a large staff rotation and need to be compliant with quality standards and QM/GMP.
Sampling data can be exported for further analysis or control by inspectors.
TRIO.BAS MONO 100 Petri PACK [ORU-201K] is including:
- 1x TRIO.BAS MONO BLUETOOTH Air sampler (100 lts/min) Petri 90 plate and 1 calibration certificate
- 1x Base Station Induction battery charger 100/240VCA 50/60Hz 35W - Power supply cable with plug SHUKO
- 1x s/s ASPI HEAD Petri plate
- 1x COVER HEAD s/s to protect ASPI HEAD
- 1x ROBUSTUS STANDARD carrying case - 48x38x17 cm
Single aspirating chamber for Petri plates with Hepa filter on air outlet.
The TRIO.BAS microbial air samplers have an electrical motor that do not produce particles after the cleaning procedure.
If the same air sampler is transferred in different environments with different levels of microbial contamination (from high to low – e.g. from C to A area), a risk of cross-contamination is possible.
In this case, to avoid this risk of transferring particles from the inside part of the aspirating chamber, it is suggested to adopt those air samplers that include an HEPA filter fixed on the air outlet of instrument.
The purpose of the filter is to stop the potential transfer of particles.
The HEPA filter is positioned externally and therefore its replacement is very simple.
- Main customers of TRIO.BAS MONO FILTER are pharmaceuticals, cleanrooms and biotech industries. The HEPA filter allows to capture the particulates
- The data is transferred via Bluetooth between the air sampler and a smartphone or tablet (Android version) and then to a PC or laptop
- The data may be transferred via cable, too. This is helpful for all companies that, due to internal policy, are not allowed to use wireless transfer
- It is possible to work either in manual or automatic mode
- Body IP 65 certified for protection from dust and water
- The battery is recharged by a power cable connected directly to the air sampler
- The use of sterile "Daily Shift" aspirating heads reduces the risk of contamination
Including with this reference:
- 1x TRIO.BAS MONO BLUETOOTH FILTER Air sampler (100 lts/min) Petri 90 plate with battery charger 100/240VCA 18VDC 859 mA with adapter for plug Eu/UK/USA - and CABLE for transfer data,
- 1 box HEPA filter and 1 calibration certificate
- 1x s/s ASPI HEAD Petri plate
- 1x COVER HEAD s/s to protect ASPI HEAD
- 1x ROBUSTUS STANDARD carrying case - 48x38x17h cm
Including:
1x TRIO.BAS MONO BLUETOOTH ATEX Air sampler (100 lts/min) Petri 90 plate and 1 calibration certificate
1x Base Station Induction battery charger 100/240VCA 50/60Hz 35W - Power supply cable with plug SHUKO
1x Stainless steel ASPI HEAD Petri plate
1x COVER HEAD stainless steel to protect ASPI HEAD
1x ROBUSTUS STANDARD carrying case - 48x38x17h cm
Including:
1x TRIO.BAS DUO BLUETOOTH Air sampler (100 lts/min) Petri 90 plate with Battery charger 100/240VCA 18VDC 859 mA with adapter for plug Eu/UK/USA - and CABLE for transfer data and 1 calibration certificate
2x s/s ASPI HEAD Petri plate
2x COVER HEAD s/s to protect ASPI HEAD
1x ROBUSTUS STANDARD carrying case - 48x38x17h cm
Including:
1x TRIO.BAS DUO BLUETOOTH Air sampler (100 lts/min) Petri 90 plate and 1 calibration certificate
1x Base Station Induction battery charger 100/240VCA 50/60Hz 35W - Power supply cable with plug SHUKO
2x s/s ASPI HEAD Petri plate
2x COVER HEAD s/s to protect ASPI HEAD
1x ROBUSTUS STANDARD carrying case - 48x38x17h cm
Including:
1x TRIO.BAS DUO BLUETOOTH ATEX Air sampler (100 lts/min) Petri 90 plate and 1 certificate with 4 calibrations (2 for instrument and 2 for Selftest)
1x Base Station Induction battery charger 100/240VCA 50/60Hz 35W - Power supply cable with plug SHUKO
2x Stainless steel ASPI HEAD Petri plate
2x COVER HEAD stainless steel to protect ASPI HEAD
1x ROBUSTUS STANDARD carrying case - 48x38x17h cm
