Fume Hoods, also known as fume closets or fume cupboards are designed with the view of protecting people and property from toxic fumes. Toxic chemicals used in the laboratories give rise to gases and fumes that harm both people and the environment. These fumes need to be cleared away immediately to ensure the safety of the people working in such environment, necessitating the use of fume hoods. Though all fume hoods follow the same basic working and design principle, only chemical fume hoods should be used for labs.
The Need for a Fume Hood
A fume hood should be used when the workers are involved in the use of materials that are near to the permissible exposure limit. Another reason for using the hood is to filter out the radioactive isotopes when using radioactive materials. When there is a growing concern that the flammable vapors might attain 1/10 of the lower explosion limit. These hoods are helpful when working with materials that are non-hazardous but emit vapors or unpleasant odors.
Features of Chemical Fume Hoods
To choose a chemical fume hood, a comprehensive analysis of the laboratory needs to be conducted. The concentration of the contaminants in the air should be determined and the particulates that pose a threat should be identified. Consult lab fume hood manufacturers to help you decide on the type of fume hood that is best suitable for your environment and for the materials used in your lab. Consider the energy efficiency of the hood when purchasing one. Hoods that follow the concept of variable-air-volume (VAV) or use two-speed systems offer great energy efficiency.
Duct or No Duct?
Ductless fume hoods get rid of the toxic particles, vapors, and fumes at a much lower cost, due to the absence of ductwork. Ductless fume hoods have some chemical and heat restrictions which might not be suitable for the general application in certain laboratories. The chemical volumes should remain below 500mls when ductless fume hoods are used.
Types of Chemical Fume Hoods
- Air Flow Hoods
Air flow is an integral part of a fume hood. For applications where the air levels within the hood need to be adjusted, customized lab fume hoods that offer variable air velocities are available.
- Thin-walled Fume Hoods
For laboratories that do not work with hazardous materials, heavy-walled hoods with accessories are not necessary. Instead, thin-walled hoods that execute the same function should be used. The lab fume hood price will be more economical for tin-walled ones.
- Walk-in Fume Hoods
Cabinet-sized exhaust fume hoods are suitable for large-scale projects where the bench hoods will not suffice. The larger hoods allow the worker to sit or stand within them and house large equipment.
Always have the hood installed from a professional installer
A chemical fume hood is nothing like the hoods found in kitchens. The placement and positioning of the hood should also be guided by the professional to ensure fume hood safety. A chemical fume hood should always be installed by a professional installer because of its complexity.
Depending on the needs, some hoods can be attached to a special conduit for leading the gases out of the building. Alternatively, a fume hood can also be attached to an incinerator for burning off the toxic gases. The hood should be properly attached to the incinerator to drive away the toxic gases.
When choosing a lab fume hood manufacturer, make sure that their products comply with the necessary safety and quality standards. The right manufacturer is as important as the right chemical fume hood. Working with a reputed manufacturer will keep you covered on the grounds of efficiency, safety, cost, and customization.