Cleanliness testing is essential for quality control in cell culture rooms, directly impacting experimental reliability, production compliance, and biosafety. This document outlines key technical points for air particle, microbial, and physical parameter testing to provide practical guidance for cleanroom management.

Airborne Particle Testing​​

Instrument Selection​​

Use a particle counter (e.g., LM-GPro series) based on light-scattering principle, with SOP sampling mode, stainless steel housing for disinfection resistance, and a 10.1-inch touchscreen. Grade A filling areas require real-time monitoring equipment.

Testing Standards​​

• Sampling points

Follow GMP and ISO 14644 standards, evenly distributing points horizontally/vertically to cover critical operation areas.

• Parameters

Use 100 L/min flow rate for Grade 100 areas, 28.3 L/min for Grade 10,000 areas, with sampling time ≥1 minute per point.

• Frequency

Perform after construction/renovation, monthly routine checks, and after major changes (e.g., HEPA filter replacement).

Microbial Testing​​

Settling Bacteria Testing​​

• Use 90mm TSA plates (SDA for fungi), placed at 0.8-1.5m height.
• Expose for 30-45 minutes, then incubate at 30-35°C for 3-5 days (20-25°C for fungi, 5-7 days). Count colonies visually.

Airborne Microbe Testing​​

• Use impact or membrane samplers (e.g., LM-AC with rotating stand, FKC portable models).
• Place sampling points 0.8-1.5m above ground, 30cm from air supply vents. Incubation conditions match settling bacteria testing.

Surface Microbe Testing​​

• Contact plate method

Use 25 cm² agar plates for flat surfaces.

• Swab method

Wipe irregular surfaces with sterile swabs, then count after elution.

Physical Parameter Testing​​

HEPA filters

Scan for leaks using photometer method per national standards.

Airflow & velocity

Verify unidirectional flow uniformity; measure key areas with a thermal anemometer.

Air changes

Calculate using "air supply volume/room volume" from hood measurements.

Pressure & humidity

Maintain ≥10Pa pressure gradient, 20-24°C, 45%-65% humidity.

Additional Testing & Procedures​​

• Noise ≤60dB, illumination ≥300 lux. Regularly test recovery time and purified water microbial limits.

Process

• Plan → calibrate instruments → sample → incubate → analyze → compare data → correct deviations (e.g., replace filters, enhance disinfection).

Through multi-dimensional testing and standardized management, combined with professional instruments and data analysis, cell culture room cleanliness can be effectively maintained, reducing contamination risks.