Collections > Master's Papers > Gillings School of Public Health > Evaluation of Laboratory Hoods in the Basement and First Floors of the Rosenau Buildings

The proper location and operation of laboratory fume hoods is essential for effective and efficient protection against exposure to hazardous substances. Two qualitative and two quantitative tests, as well as other observations, were applied in the evaluation of 22 laboratory fume hoods in the basement and first floors of the Rosenau Building. The two qualitative tests allowed for visualization of the air currents inside and outside of the hood. Smoke tubes were used to assess air currents in front of the hood face, while titanium tetrachloride(TiCl4) was applied to the inner sides and bench of the laboratory fume hood to visualize the air current's behavior within the hood face. The quantitative tests measured face velocity and hood performance (with the use of Sulfur Hexafluoride(SFg) as a tracer gas). Other observations include layout of the room, condition of the hood bench, sash position during operation, location of windows, doors, make-up air units and general work practices which could affect cross-draft currents in front of the hood face. The presence of bottom slots leading to plenums were noted and maintenance records were reviewed during each hood evaluation. Recommendations are given for ways to improve each hood's efficiency and effectiveness.