For fume hoods to provide this important protection, technicians and laboratory personnel must use it effectively and correctly. Here are some tips to ensure that your laboratory fume hood is adequately protected from toxic fumes, chemical leaks and hazardous reactions.
Minimize air disturbances
Air turbulence reduces the efficiency of the fume hood. That's why finding the right place is critical to maintaining good work order.
After installing a fume hood, place it in a location where cross-flows can be avoided. Many things cause a cross flow, including:
1. People move around
Door opening and closing
3.Window
4.Supply air diffuser
5.External fan
Although avoiding high-flow areas is important to ensure maximum contamination control, so is laboratory staff moving around fume hoods. Avoid rapid movement in and out of the fume hood, otherwise air interference may result.
Make sure the exhaust is normal
Before starting work, laboratory technicians should always ensure that the exhaust is normal. Exhausting smoke is the main job of the fume hood, so if this part of the ventilation system is not working, the fume hood will not function effectively.
When making sure the exhaust works, check the baffle. These are removable partitions that form openings in the rear of the fume hood. They maintain uniform airflow, which increases efficiency. Look for any obstacles that may be blocking the airflow.
Also, if the fume hood contains an airflow monitor, check the status of the monitor periodically. Ensuring its proper operation will enable you to better check for any suspicious airflow changes.
Good operating procedures
Even in equipment with a special fume hood design, high efficiency can only be achieved if the equipment is used effectively. Following the correct operating procedures is key.
Each type of fume hood has its own set of manufacturer's instructions and procedures. However, examples of good laboratory fume hood procedures typically include the following:
When there is large equipment inside the fume hood, place the shelf under the equipment so that air can flow under it.
Always keep the fume hood closed unless you are commissioning the equipment or working in the fume hood.
Keep any container or equipment 6 inches or more away from the surface of the fume hood.
To maximize performance, keep the sash windows closed as much as possible. If a power outage occurs, lower the fume hood window fan to within 1 inch. The chimney effect is created by allowing some air to continue to flow into the fume hood.
pay attention
Such as paper products, chemical wipes and aluminum foil. Lightweight materials such as these can be easily drawn into the exhaust port, obstructing airflow.
If using a bench fume hood, use a sliding sash barrier. It protects you and keeps your face outside the work area.
Priority management and maintenance
Combining proper housekeeping and updated maintenance procedures is essential to ensure the efficient and high-performance operation of your laboratory fume hood.
Some housekeeping and maintenance procedures to be implemented include:
1. Do not store items (including chemicals) in a fume hood. Not only do they block airflow, they can also interfere with pollutant control. Vanderbilt University Medical Center recommends keeping at least 50% of the work surface clean at all times.
2. Store dangerous chemicals in an approved safety cabinet. If the surgery requires chemicals, just keep the minimum amount in the fume hood. Biological safety cabinets have different functions and are specifically designed to prevent exposure to biological materials. It is important to use the right cabinet for the specific chemical or biological material.
If you operate a ductless fume hood, be sure to check your fume hood filters to make sure they are clean or need to be replaced. When cleaning, carbon filters play an important role in removing harmful fumes and particles from the laboratory.
Before use, not only should the fume hood be blocked for airflow, but also excessive turbulence.
Fume hood certification is required at least annually to ensure safe operation. Typical tests may include surface wind speed tests and smoke tests. The certification body will also perform tracer gas control tests. These types of tests are especially important because face velocity does not always accurately predict leaks in a fume hood.
Clean up spills immediately. If splashing occurs, make sure to wipe the liquid off the fume hood glass.
If your fume hood is not operating properly, contact the manufacturer immediately to test your fume hood. Proper maintenance is the key to ensuring that your laboratory fume hood continues to work effectively and to protect field technicians from dangerous reactions and toxic fumes.