Downflow Booths

An image of a Hokokawa Micron downflow booth

Product Description

Hosokawa Downflow Booths offer a safe working zone for operatives. They provide protection from harmful, hazardous, toxic, or sensitizing dusts which are generated during manual powder handling activities such as sampling or dispensing. This also includes charging and offloading sub-division from powders or solvents, drum loading, and unloading.

  • Operator Exposure Levels (OEL) typically between 50 and 100µg/m3 TWA/Task Duration.
  • Lower levels of containment can be achieved by using containment screens.
  • Processing or packing equipment and drum handling equipment can also be integrated within the ergonomic design.
  • Safer and more user-friendly than PPE (Personal Protective Equipment)

The downflow booths use HEPA filtered air to push dust or vapours down and away from the operator breathing zone, creating a clean processing zone and minimising cross-contamination risk with other products/processes. This allows a wide range of process operations to be carried out without the need for PPE.

Our downflow booths are available in a range of standard and bespoke configurations to suit individual requirements of operator protection and product protection, the processing activities to be undertaken, and any environmental and energy concerns.

Downflow booths have predominantly been used in the pharmaceutical, fine chemical, cosmetics, and food industries. However, they are becoming increasingly common in other areas, including the metal finishing and sampling industries.

There are two main configuration options, depending on the application:

  • Recirculatory booths are typically used in dry powder handling operations and achieve a minimum H13 grade 99.995% @MPPS filtration performance. A conditioned downflow of air passes evenly from the booth’s ceiling inlet plenum, pushing any dust downwards and away from the operator’s breathing zone. The air is then extracted from the booth via low-level exhaust grills and through a series of filters prior to recirculation into the booth’s working area. A small percentage of air is discharged from the booth through high-level bleed to maintain the working space under negative pressure, minimizing airborne contamination from leaving the booth.
  • Single pass, once-through booths are used in applications where solvent fumes or vapours are anticipated, or when high potency products demand a once through philosophy. The single pass booth operates a vertical airflow, pushing dusts and vapours downwards and away from the operator’s breathing zone with air discharged 100% to atmosphere, ensuring that solvent laden air will not be recirculated back into the booth.

Latest Developments in High Containment

By combining clean air technology and barrier screen protection between the operator and the source of dust particles, our Downflow Booths can achieve OELs as low as <1µg/m3, which is consistent with more robust, fully enclosed containment methods.

5D Articulated Containment Screens offer a range of movements: side to side; forward and backward; raise and lower; controlled tilt function; controlled rotation; to give operators ease of movement with minimal restriction. Optional materials of screen construction include rigid and flexible transparent materials.


Our Downflow Booths are offered fully constructed in powder coated steel, 304/316L stainless steel or a combination of both or a composite ‘clean room panel’ material of  rigid polyurethane foam core between metal faced panels. The downflow booth’s open fronted design offers unrestricted operator access. Flexibility in design enables a large range of container types ie. IBCs etc. to be handled.

A range of optional features enable customers to select specific Downflow Booth enhancements to achieve a more bespoke containment and processing solution:

  • Energy Conservation Mode of Operation. Offers stand by mode when downflow booth is not in full operation. New high efficiency EC fan technology, motor assemblies, LED  lights etc.
  • Filtration Monitoring with Alarm Function. Filter blocked alarms (audible and visible)
  • 5D High Containment Screens. Rigid containment screens deliver five axes of movement and fitted with glove ports for improved operator protection (OEL 1μg/m)
  • Personnel/Materials Airlocks to provide a pressurized bridge between a controlled air environment to an unregulated area, preventing entry or egress of potentially harmful or unwanted contaminants
  • Bag-In, Bag-Out Filtration. Triple stage, safe change filtration (pre filter, fine duct, HEPA) enables maintenance personnel to remove contaminated particulate filters without coming in direct contact with the hazardous contaminants or internal booth surfaces during filter change
  • Temperature Cooling Package. Cooling fan or chiller coil system for temperature regulation
  • Integrated Equipment including vacuum manipulators, manual/automated drum tippers, roller conveyors and turntables for a more seamless operation
  • FAT/SAT, IQ/OQ protocols
  • Safe Work Zones from 1800mm to 2300mm
  • Safe Area or Explosion Proof Electrics


  • 400V 3ph + E + N / 50Hz
  • 480V 3ph + E / 60Hz
  • Other voltages available on request

Light levels<750lux