Hosokawa Down Flow Booth Demonstration

Hosokawa’s Vitalair Downflow Booths protect operators from harmful dust and vapors generated during material handling processes by drawing contaminated air downwards, away from the breathing zone. These systems can achieve operator exposure levels (OEL) typically between 10 to 100 ?g/m3 or better. The fully customized booths provide safer working environments for operators during material handling, transferring, sampling, and loading processes. The video demonstrates some of the functions of the downflow booth.

New Developments for High Containment  By combining clean air technology and barrier screen protection between the operator and the source of dust particles, Hosokawa’s Downflow Booths are capable of achieving OELs as low as <1 µg/m3, which is consistent with more robust, fully-enclosed containment methods.

5D articulated containment screens offer a range of movements including side to side, forward and backward, raise and lower, controlled tilt function, and controlled rotation to give operators ease of movement with minimal restriction. Opti Hosokawa Vitalair Downflow Booths offer a safe working zone for operators by delivering protection from harmful, hazardous, toxic, or sensitizing dusts generated during manual powder handling activities including sampling, dispensing and charging and offloading sub-division from powders or solvents, drum loading, and un-loading. Processing or packing equipment can also be integrated within the ergonomic design.

The Downflow Booth uses HEPA filtered air to push dust or vapors down and away from the operator’s breathing zone, creating a clean processing zone and minimizing cross contamination risk from other products/processes. Downflow Booths offer a safe and more user friendly alternative to the wearing of restrictive PPE (Personal Protective Equipment) and allow a wide range of process operations to be carried out without the need for PPE.

Depending upon the application, there are two main design alternatives:

  • Re-circulatory 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 extracted from the booth via low level exhaust grilles 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 vapors are anticipated or when high-potency products demand a once-through philosophy. The single-pass booth operates a vertical airflow, pushing dust and vapor downwards and away from the operator’s breathing zone with air discharged 100% to the atmosphere, ensuring that solvent-laden air will not be recirculated back into the booth.

Although typically used in pharmaceutical, fine chemical, cosmetics, and food industries, the use of downflow booths is now common in metal finishing, sampling, and other industries.