The design and construction of fume hoods have evolved significantly over the years, with newer generations offering several improvements over the older ones. Older fume hoods were typically lined with asbestos panels as an industry standard for chemical resistance, but the use of asbestos was discontinued after 1988 due to safety concerns. In addition, many older designs had raised airfoils that could cause spills, used non-military grade cables for vertical sash operations that became frayed and imbalanced over time, and provided limited visibility and light due to their small sightline. They also lacked a secondary spill trough or cable pass-through, which is now a standard feature for spill containment.

Older hoods were “constant volume” or “auxiliary air” type, which meant they always exhausted the maximum amount of air, even when closed or not in use. In contrast, newer hoods use VAV systems or low flow technology, resulting in high operating cost savings. The newer hoods also have lower static pressure, allowing them to operate more efficiently and with less noise. They also have a sill and can meet ASHRE 110 standards.

While older equipment was painted with baked-on epoxy paint that provided no UV protection and became discolored over time, newer hoods are powder-coated, eliminating discoloration, and can be branded with laser-cut logos. In addition, newer hoods are equipped with LED lighting instead of fluorescent lighting.