What is a powder weighing cabinet?
A powder weighing cabinet or balance enclosure is a cabinet type that protects the operator against the powder products that are being manipulated inside the cabinet. Often the application is weighing. The ventilator pulls the air from the cabinet and directs it trough a HEPA H14 filter that captures the particles.
A powder weighing cabinet sends the air back into the lab after filtering it. A ducted fume hood sends the air outside using an HVAC system. When manipulating powders, the ducted fume hood comes with 2 problems:
- It is connected to the outside, so the variable flow rate of the wind will influence the flow rate of the air in the cabinet. This means pressure fluctuations that can influence the results of the weighing.
- Powders are heavier than air. In the turns of the HVAC system, powders tend to stay behind due to the centrifugal force.
These 2 factors make the powder cabinet a much better solution for weighing powders.
HEPA H14 filters are particle filters. Particles can be dust or microdroplets. Most liquid chemicals have evaporation of molecules that are not captured by the HEPA filters. Despite this, there is a solution. Carbon filters can be mounted on top of the HEPA filters. Carbon filters are filled with active charcoal that contains chemical coatings. These coatings can capture molecules by using a process called adsorption
When products get more dangerous, there are 2 considerations for the cabinet choice:
The filter replacement procedure: during filter replacement, it is possible that particles get released from the filters and get airborne again. So for the protection of the service engineer doing the replacement and the staff working in the lab, a safe filter replacement procedure like BIBO (Bag-In-Bag-Out) need to be considered. If BIBO is required, Analis can offer the Esco Ventilated Balance Enclosure.
Brochure Esco Ventilated Balance Enclosures EN
Open versus closed systems. Open systems are more convenient to work with and come with a lower investment cost. Closed systems provide a better containment due to the physical separation between the users and the product. If a closed system is required, Analis can offer Esco Healthcare Platform Isolators.
The ideal solution for hazardous weighing operations.
ERLAB secure weighing station guarantees an outstanding level of safety for users. It provides the required stability as well as the level of accuracy (up to 0,01 mg) required when weighing in the laboratory. It is the ideal solution for hazardous operations which require a confined environment, eliminating any risk of personnel being exposed to toxic products.
Containment and filtration guaranteed by their compliance with the AFNOR NF X15-211 standard.
The exclusive eValiQuest service assesses the risk of your operations and reduces any risks associated with your system.