Benchtop Fume Hood

What is the Benchtop Fume Hood?

A benchtop fume hood is a compact ducted hood that sits on an existing bench or cabinet. It suits low-volume chemical work in limited space, such as small teaching or quality control laboratories.

Overview

The hood has a compact body, widths of 750–1200 mm, depth of 600–700 mm and height of about 1000–1200 mm. Exhaust volume is 300–800 m3/h, with face velocity of 0.4–0.5 m/s at a sash opening of 400–500 mm. It is constructed from epoxy-coated steel, polypropylene or stainless steel, with a fixed or sliding sash and LED lighting. Service fittings are optional, and it connects to a duct of diameter 150–250 mm. The unit sits on a bench rated for its weight, typically 150–250 kg, and requires sealing to the worktop. Benchtop hoods are quiet, lower in energy use than floor-standing types and easy to relocate, but have limited workspace and cannot accommodate tall apparatus.

How does it work?

A ducted fume hood creates a controlled inward airflow through the sash opening so contaminants generated inside are carried to the exhaust rather than into the room. Face velocity, typically 0.4–0.6 m/s at the sash, is produced by an exhaust fan located on the roof or in the duct. A baffle system at the rear distributes air across slots at the top, middle and bottom to avoid dead zones. A bypass airfoil keeps flow smooth as the sash moves. Variable air volume (VAV) hoods modulate exhaust as the sash opens or closes, saving energy while holding face velocity. The work surface, liner and sash are chemical resistant. Airflow monitors, alarms and lighting complete the hood, and the building make-up air system replaces exhausted air.

What are the key features?

• Compact body of 750–1200 mm width
• Exhaust volume 300–800 m3/h
• Epoxy steel, PP or stainless steel construction
• Fixed or sliding sash with LED lighting
• Sits on existing bench and seals to worktop
• Lower energy use than floor-standing hoods

What are the technical specifications?

A typical benchtop fume hood configuration offers width of 750 / 900 / 1200 mm, depth of 600–700 mm, height of 1000–1200 mm, exhaust volume of 300–800 m3/h, face velocity of 0.4–0.5 m/s and sash opening of 400–500 mm. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The Benchtop Fume Hood is used in small teaching laboratories, quality control, sample weighing and low-volume chemistry. Across the wider Ducted Fume Hoods class, laboratories also deploy it for chemistry laboratories, pharmaceutical research and materials testing.

Which standards and certifications apply?

Relevant standards and methods include EN 14175-2 (fume cupboards, safety and performance), EN 14175-3 (type test methods), EN 14175-4 (on-site test methods), ASHRAE 110 (method of testing performance of laboratory fume hoods), GB/T 34269 and ISO 14644-1. Certification candidates for this model are CE and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Commission each hood with a face velocity survey and, where required, a containment test such as EN 14175-3 or ASHRAE 110. Place it away from doors, walkways and supply diffusers, since cross-drafts above 0.15 m/s degrade containment. Keep the sash at or below the marked working height, and avoid blocking baffles with equipment. Check airflow monitors, alarms and exhaust fans at least every 6–12 months, and clean the liner regularly. Plan make-up air so the room does not become negatively pressured. Train users and label the hood with its tested face velocity and date, and do not use it for storage of chemicals beyond what the work requires.

How do I select the right Benchtop Fume Hood?

Choose a benchtop hood for small-scale tasks in limited space with an existing bench. It is not suited for tall apparatus or heavy equipment. Confirm duct routing and bench rating before order. RFQ: width, bench load rating, duct diameter, liner material and services.

How does it compare with other Ducted Fume Hoods variants?

Select the hood by the chemicals and process. Choose width, commonly 1200, 1500 or 1800 mm, to match equipment and operators, and check that depth and height suit tall apparatus. Decide between constant volume, bypass and VAV designs, taking the building's exhaust capacity and energy costs into account. Specify liner material: fibre-reinforced cement or epoxy for general use, stainless steel or polypropylene for acids. Consider sash type, vertical or combination, face velocity monitoring, service fittings and base cabinet for storage. Confirm whether perchloric acid or radioisotope work requires a specialised hood instead. Coordinate duct size, fan capacity and make-up air with the building engineer, and plan for containment testing.