Fume hood

A fume hood having a work chamber with an inlet and an outlet, an air flow regulator for maintaining a predetermined air velocity through said inlet into said chamber, and a pitot in communication with said air low regulator to measure air velocity at the inlet of said chamber, said pitot comprising:

• a) upper and lower surfaces, a substantially horizontal rear section extending into said chamber, a front section extending to the exterior of said chamber, a front edge and a rear edge;
• b) an exterior air pressure sensor at the front edge of said pitot, said exterior sensor being a first tube positioned substantially parallel to said inlet, said first tube including a continuous wall defining a hollow interior, and at least one air access opening in said wall in communication with said interior and being inclined downwardly at an angle of from about 30° to about 50°;
• and
• c) an interior air pressure sensor at the rear edge of said pitot;
• said interior air pressure sensor including said interior air pressure sensor including a hollow interior and rear openings into said interior substantially equidistant between said upper and lower surfaces.

A pitot to measure air velocity at the inlet of a fume hood chamber comprising:

• a) a substantially horizontal rear section extending into said chamber and a front section extending to the exterior of said chamber, said airfoil having upper and lower surfaces, a front edge and a rear edge;
• b) a front air pressure sensor including downwardly inclined openings at the front edge of said airfoil;
• and
• c) a rear air pressure sensor at the rear edge of said pitot said rear sensor including openings substantially equidistant between said upper and lower surfaces, said sensors being in the form of tubes positioned substantially parallel to said inlet, each tube having a continuous wall defining a hollow interior, said openings in said rear sensor being in communication with said interior.