Frequently Asked Questions (FAQs)

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Q.

What is a filtered workstation?

A.

Filtered Workstations are primary engineering controls designed to protect the operator from hazardous fumes or vapors. Filtered Workstations use a blower to pull contaminated air through carbon and/or HEPA filters and return clean filtered air back into the environment.

Q.

Are ductless fume hoods safe?

A.

Ductless fumes are safe, but applications should be verified by a professional prior to use. Ductless fume hoods often employ additional safety measures to ensure safe operating conditions such as; airflow sensors, filter breakthrough sensors, and ports for supplemental filter testing.

Q.

Do ductless fume hoods need to run continuously?

A.

Ductless fume hoods do not need to run continuously. Ductless fume hoods typically offer blower controls to allow for easy on/off control.

Q.

How often do carbon filters need to be replaced?

A.

Carbon filters have finite capacity based on the amount of carbon contained in the filter. Most carbon filters have recommended replacement on an annual interval. This ensures no risk of filter breakthrough or exposure. Many ductless manufacturers utilize electronic sensors to monitor the exhaust air and indicate when a filter is nearing saturation and should be changed out. Filter life is directly related to a variety of factors including; the type of chemical, the volume of chemical evaporated, frequency of use, and at what temperature is the chemical being handled during use.

Q.

What is a safety filter?

A.

Safety filters are filters that protect the environment from potentially contaminated carbon dust produced from granular carbon filters. A safety filter (failsafe carbon or HEPA/carbon blended filter) acts as a backup if the primary filter fails.

Q.

How can I monitor my carbon filter?

A.

Many ductless fume hood manufacturers offer monitoring devices built into the system. We have safety sensors to check the filter exhaust for breakthrough, and colorimeter tube testing can be employed to provide a ppm readout for target chemicals in the exhaust stream.

Q.

Can ductless fume hoods maintain a set face velocity?

A.

Many ductless fume manufacturers offer face velocity monitoring to measure the velocity at the sash. Some ductless fume manufacturers offer automatic blower control that adjusts the blower to maintain a face velocity. Others simply incorporate a simplistic visual indicator that verifies airflow.

Q.

What are the benefits of a ductless fume hood?

A.

Ductless fume hoods offer many benefits compared to total exhaust. Ductless fume hoods are portable which eliminates the need for installation, they are lower in energy costs due to exhausted conditioned air, and they trap chemicals rather than exhausting them into the environment.

Q.

How long can ductless fume hoods operate?

A.

Ductless fume hoods can have lifetimes exceeding total exhaust fume hoods. Although the life span of a ductless fume hood is based primarily on environment and use, construction materials like lab-grade polypropylene can extend fume hood life by preventing rust or corrosion.

Q.

What is PCR?

A.

Polymerase chain reaction (PCR) is an amplification technique for DNA/RNA which is frequently used in diagnostic testing, forensics, and genomics.

Q.

What does ISO 5 or Class 100 mean?

A.

The International Organization for Standards (ISO) has cleanliness standards for cleanrooms. ISO 5 means an environment with a maximum of 100 particles greater than or equal to 0.5 microns per cubic foot of air. Class 100 was the Federal Standard that was used prior to the global adoption of the ISO 5 designations.

Q.

How do HEPA filters work?

A.

High-efficiency particulate air (HEPA) filters are mechanical filters designed to filter particulates. HEPA filters physically block particles from passing through. They provide an efficiency value based on most penetrating particulate size (MPPS) such as 99.997% effective at 0.3 microns.

Q.

What is the lifetime of a HEPA filter?

A.

High-efficiency particulate air (HEPA) filters typically improve in efficiency as the filter is used. HEPA filter lifetime varies based on environment and use but most manufacturers suggest replacement between 1-3 years. The general test for a HEPA filter to be changed out is when the pressure drop across the filter is twice the amount relative to installation.

Q.

What is the difference between a PCR Workstation and Dead Air Box?

A.

High-efficiency particulate air (HEPA) filters typically improve in efficiency as the filter is used. HEPA filter lifetime varies based on environment and use but most manufacturers suggest replacement between 1-3 years. The general test for a HEPA filter to be changed out is when the pressure drop across the filter is twice the amount relative to installation.

Q.

Is the PCR Workstation a biological safety cabinet?

A.

Biological safety cabinets offer a minimum of personnel and environmental protection. The PCR Workstation protects the samples but does not protect personnel or the environment from samples handled. The PCR Workstation does not meet the requirements or definition of a biological safety cabinet.

Q.

What is the lifetime of a UV bulb?

A.

The UV bulbs in an AirClean Systems workstation are designed to operate for 1000 disinfection cycles and deliver an adequate level of energy to decontaminate the workstation. The UV bulbs are manufactured to provide a specific dose of UV irradiation for surface disinfection.

Q.

Is UV light dangerous?

A.

UV light can damage cells and various forms of UV irradiation may cause cancer. Our polycarbonate shields naturally reflect UV-C light to protect the operator during surface disinfection.

Q.

How do carbon filters work?

A.

Carbon filters are used to filter out contaminants from gas or liquid solutions. In gaseous filtration, as fumes pass through the carbon filter, Van Der Waals forces trap the chemicals on the carbon's surface.

Q.

What is activated carbon?

A.

Activated carbon is a form of carbon that has been treated to increase surface area for filtration efficiency. Activated carbon is commonly used in carbon filters because the treating process increases filter capacity.

Q.

What is a granular carbon filter?

A.

Granular carbon filters are gas-phase filters that filter potentially hazardous chemical fumes or vapors. Granular carbon filters use closely packed, loose granular carbon. They can potentially produce contaminated dust and experience carbon shifts in shipping. This leads to dead spots on the filters.

Q.

How is carbon 'activated'?

A.

Activated carbon is typically treated with steam, pressure, or chemicals to increase adsorption capacity. This treatment creates an extremely porous structure with enhanced surface area to capture chemicals.

Q.

Why are coconut shells used to produce activated carbon?

A.

Coconut shells are an excellent raw material source used to produce activated carbon due to their high carbon content and hardness. The raw materials are often sourced in regions where coconuts are harvested, including Malaysia, India, Sri Lanka and the Philippines.

Q.

How is coconut shell-based activated carbon produced?

A.

Raw material coconut shells are first charred at the coconut grower or at a facility designed to produce char. The char is then purchased by activated carbon manufacturers where it is activated at elevated temperatures by using steam in a kiln or furnace. The final product is screened to a variety of mesh sizes for both vapor phase and liquid phase applications.

Q.

How do the characteristics of coconut shell-based carbons compare to those for coal-based carbons?

A.

Activated carbons produced from coconut shells typically have a tighter, more microporous pore structure than their coal-based counterparts. This is due to the inherent pore structure of the raw material coconut shell as compared to raw material coals. This microporosity lends itself towards certain applications where activated carbon is used. Also, coconut shell-based carbons tend to be harder, more resistant to abrasion, and lower in ash than similar grades of coal-based carbons.