Fume hoods are used to capture potentially hazardous chemical fumes, mists and dusts and remove them from the breathing space of the operator. Therefore, properly engineered fumes hood ventilation as well as effective use and maintenance of fume hoods is of critical importance. The typical laboratory fume hood includes a working space within the hood and a fume hood sash that can be raised or lowered at the face of the hood. Proper placement of equipment and chemicals inside the hood can affect the effectiveness of the air flow to keep hazardous chemicals from entering the breathing space of the operator. Additionally, the design and maintenance of the ventilation system and the effective use of the fume hood sash are also important aspects to consider.
Time and again we find commercial and/or custom fume hoods that are not performing as desired due to a number of reasons such as:
- poor design;
- inadequate maintenance;
- disabled or missing flow indicator;
- lack of training on the proper use of a fume hood and sash to control laminar air flow;
- operator unfamiliarity with or misuse of the equipment.
In some cases, the roof-top discharge of chemical fume hoods has been placed too near HVAC systems designed to introduce clean air into the building and as a result, the HVAC system draws in exhaust from the fume hoods and degrades indoor air quality.
In order to produce optimal results, fume hood flow rate must be evaluated on a regular basis. This is a documented, specific analytical and diagnostic process. Appropriate and calibrated flow measurement equipment must be used. Fume hoods must have a working flow indicator to alert the operator of the function of the local exhaust associated with the hood.
Ask us to conduct comprehensive fume hood ventilation surveys for your business.