Bypass Hood

Bypass Fume Hood

LOC’s Bypass Fume Hood provides continuous air flow across the work surface even when the sash is closed. The fume hood features an internal, alternative opening located above the sash. This allows for a constant air volume which allows for change in the hood’s face velocity. In operation, the bypass exhaust system works automatically, in conjunction with the hood sash. The bypass adjustment is made as the sash is opened and closed creating a relatively constant air volume regardless of sash position.


  • Equipped with a full view sash providing an unobstructed view of the hood interior.
  • Sash is 7/32″ laminated safety glass with full width flush PVC pull and spring loaded sash stop.
  • Includes audible LOC500 airflow monitor for safety.
  • Counterweight provides a one finger sash operation.
  • Hood entrance is framed with inward-angled members to minimize turbulence and provide smooth air movement in hood at face velocities ranging from 60 to 150 FPM.
  • Stainless steel airfoil allows 1″ of airflow across the work surface when sash is in the closed position.
  • Double wall construction for ease of routing plumbing/ electrical lines.
  • Standard “Resin-Chem” interior liner with removable access panels on both sides.
  • Removable exterior side panels.
  • Light is mounted above a sealed safety glass panel keeping corrosive fumes and hazardous vapors isolated.
  • Tube lights can easily be replaced through the top front.


  • A variety of optional service fixtures are available.
  • Our LOC representatives work closely with customers in specifying the type of fixtures and electrical receptacles required.


Bypass Fume Hood Dimensions

Bypass Fume Hood Specs

The static pressures listed above are for the hoods only. An appropriate amount will need to be added to this figure to compensate for the pressure drop through the duct system. The total pressure drop through the hood and the duct system must be known to select the proper exhaust blower.

Additional Resources