Essential for Cleanrooms: Air Showers

Two Core Functions

Surface Air Showering and Dust Removal

A fan drives air through pre-filters and HEPA filters, discharging a high-speed, clean airflow via 360° adjustable stainless steel nozzles (standard outlet velocity ≥25 m/s). The airflow's shear force dislodges dust and microorganisms adhering to cleanroom garments; the dislodged dust is captured by the return air system for re-filtration and recirculation, significantly reducing the number of particles introduced into the clean zone. The shower duration is adjustable (typically 10–20 seconds) and triggered automatically by infrared sensors; the air shower process is generally not performed when personnel exit the clean zone.

Airlock Isolation and Pressure Differential Maintenance

The unit features an electronically interlocked dual-door system that prevents both doors from opening simultaneously. This blocks direct airflow between clean and non-clean zones, protecting the positive pressure gradient of the cleanroom from disruption during personnel entry and exit, preventing the backflow of contaminated external air, and acting as a dynamic airlock.

Basic Structural Components

The unit comprises the housing, interlocked doors (with tempered glass viewing windows), an external-rotor fan, pre-filters, H13/H14 HEPA filters, adjustable spherical nozzles, a return air system, infrared sensors, and a control panel.

Housing Material: 304 stainless steel is the standard for pharmaceutical and food industries due to its resistance to disinfectant wiping and a design free of "dead zones" (hard-to-clean areas); 316L stainless steel is selected for highly corrosive GMP environments; anti-static cold-rolled color-coated steel may be used for standard Class 100,000 workshops.

Filtration Logic: Pre-filters capture large particles, while HEPA filters remove 0.3μm particles with ≥99.99% efficiency; contaminated air is recirculated via bottom return vents rather than being exhausted directly to the outside.

Mainstream Types and Application Scenarios

Single-Person Air Shower:Compact design suitable for small laboratories, small workshops, and low-traffic areas. Configurations include single-side, double-side, and triple-side (side walls plus ceiling nozzles) blowing; the triple-side mode ensures comprehensive coverage without dead zones, making it ideal for high-grade cleanrooms.

Two-Person / Multi-Person Air Shower Tunnel: Allows multiple people to pass through simultaneously; suitable for pharmaceutical facilities, medical device manufacturing, and high-volume production lines to improve traffic efficiency during shift changes. Cargo Air Shower: Designed for the entry of materials and transfer carts into cleanrooms; features a spacious interior to accommodate large items, serving as an alternative to personnel air showers for bulky cargo.

Specialized Custom Models: Anti-static models for electronics and semiconductors; explosion-proof models for lithium battery and chemical industries; negative-pressure models for biosafety laboratories; and automatic sliding-door models for high-traffic facilities.

Distinction: Air showers are for personnel or large carts; pass boxes are strictly for small materials only—personnel entry is prohibited.

Key Technical Parameters

Measured nozzle outlet air velocity must be ≥25 m/s (26–30 m/s is recommended for high-grade GMP facilities); insufficient velocity renders dust removal ineffective. Acceptance testing requires multi-point measurements 10–30 cm in front of the nozzles, rather than relying solely on nameplate specifications.

Filters: Standard H13; H14 HEPA filters are preferred for sterile environments and GMP Grade D or higher facilities.

Interlock systems must be reliable and include an emergency manual release for power outages.

Interior wall seams must be smooth with no dust-trapping dead zones, facilitating easy daily wiping and disinfection.

Daily Maintenance Points

Pre-filters: Clean or replace regularly (typically every 1–3 months); HEPA filters: Replace based on pressure differential readings (excessive pressure indicates a clogged filter).

Wipe and disinfect the interior weekly using lint-free cloths; keep the interior free of debris to prevent secondary dust generation.

Periodically verify nozzle air velocity and inspect door seals for aging and interlock systems for malfunctions.

For GMP projects, retain records of air velocity and filter testing for audit purposes.