Sometimes known as a fume cupboard or fume closet, fume hoods all are designed with the same basic function in mind. They protect both people and property from escaping gases. Fume hoods all follow the same basic design construct as well. Contaminated air is pulled into the hood and is forced from the area in question, then is released into the outside environment.
Will Just Any Fume Hood Do?
But not all fume hoods fit one size, or at least one scenario. These hoods come in different heights, issue different kinds of warnings, and increasingly, perform secondary functions in addition to their basic purpose. As the saying goes, “you don’t bring a knife to a gunfight”, and likewise, expecting one type of hood to cover all potential situations can result in ineffective and quite possibly dangerous outcomes. So when looking at more than one option for fume hood choices, how does a lab or floor manager make the right one? Read on to learn more about fume hood types and how to determine which is the right type for particular work.
How Do I Know I Need A Fume Hood?
Also known as a “lab fume hood” or “exhaust fume hood”, this type of hood is appropriate for use when workers are using materials that at airborne levels are at or might potentially reach the permissible exposure limit (PEL) of the material being used. Other reasons for using this type of hood would be concerns that flammable vapors may reach 1/10 of their lower explosion limit. They can also be used to filter out radioactive isotopes when working with radioactive materials. Because of increasing levels of sensor sophistication and the needs of workers, many of these hoods now can warn workers about material spills and adverse levels of oxygen and carbon dioxide in a work area. They’re also useful when working with non-hazardous materials that may still emit unpleasant odors or vapors if not contained.
Chemical Fume Hood Options
- Air Flow
While air flow is an essential part of any exhaust fume hood system, some work calls for the ability to adjust the level and amount of air within the hood. Hoods are now available that allow for more customized air velocities with air bypass systems. And other hoods allow workers to expand upon air volume within the hood when needed with a “makeup air” option that can supply additional air from outside sources, increasing total air capacity within the hood by 70%. And for labs and work areas that don’t want to risk modifying designs to meet their needs, lab fume hoods with variable air volume (VAV) are available to be installed and used with lab specific controls.
- Thin-Walled Fume Hoods
Not all labs and work areas are working with hazardous materials. In such cases, heavy walled hoods with all of the expensive accessories would be an unnecessary expense. For such work, managers should instead consider thin walled hoods which performs the same function as a heavier walled lab fume hood but is much more economical.
- Walk-In Fume Hoods
But what if a project is bigger than the “bench” accommodations that a traditional fume hood provides? Cabinet-sized exhaust hoods are now available that can house larger pieces of equipment and allow workers to stand or sit within them.
And Make Sure…..
When working with hood manufacturers, always make sure that the company’s products are ASHRAE 110-1995 certified, which means that they have passed all safety testing, and meet industry and Federal requirements.
With all of the lab fume exhaust hood options out there, it can be difficult to decide what’s best for your needs. That’s why choosing the right manufacturer is as least as important as finding the right chemical fume hood. Working with the right company means that your needs will be covered in terms of customization, efficiency, and cost as well as safety.