Chemical Hood Guidelines
Once a chemical hood is installed in a work area, it must be used properly to be effective. For use of hazardous chemicals warranting local ventilation controls, the following guidelines should be observed:
- Conduct all operations that involve hazardous chemicals inside a hood.
- Keep all apparatus at least 20 cm. back from the face of the hood and keep the slots in the hood baffle free of obstruction by apparatus or containers. Large equipment should be elevated at least 20 cm. off the base of the fume hood, to allow for the passage of air underneath the apparatus.
- Do not use the hood as a waste disposal mechanism except for very small quantities of volatile materials.
- Minimize storage of chemicals or apparatus in the hood.
- Keep the hood sash closed (up to 5 cm. from the bottom) at all times except when the hood is in use.
- Minimize foot traffic and other forms of potential air disturbances past the face of the hood.
- Do not have sources of ignition inside the hood when flammable liquids or gases are present.
- Use sash as a safety shield when boiling liquids or conducting an experiment with reactive chemicals. Nevertheless, safety goggles must be used.
- In case of malfunction report to your supervisor and to the maintenance center.