NOTICE

Hurricane Irma Update

The Air Science office is currently closed.
As Hurricane Irma passed through Fort Myers this weekend, the Air Science facility sustained minor damage to two of our buildings. We expect to be back in operation as soon as it is safe for our employees to secure their own homes and return to work.
Please contact us at info@airscience.com as usual; this address will be monitored continuously.
We thank you for your understanding.
La oficina de Air Science está actualmente cerrada.
Cuando el huracán Irma pasó por Fort Myers este fin de semana, la instalación de Air Science sufrió daños menores en dos de nuestros edificios. Esperamos volver a trabajar tan pronto como sea seguro para nuestros empleados asegurar sus propios hogares y volver al trabajo.
Comuníquese con nosotros en info@airscience.com como de costumbre; esta dirección será monitoreada continuamente.
Gracias por su comprensión
With power restored, we are pleased to announce that the Air Science factory and offices will re-open on Wednesday, September 13, 2017.
Due to Hurricane Irma, we may see some delay in processing quotation requests. As our staff returns from evacuation we will reduce the backlog. All previous quotation requests have been accumulated in our queue and will be processed as soon as soon as possible.
Please contact us at info@airscience.com as usual; this address is being continuously monitored.
Thanks for your patience and understanding during this event.
Attention Air Science Employees
Both first and second shifts should report to work on Wednesday, September 13, 2017, as soon as it is safe for you to do so. Please contact us at the numbers provided to let us know how you and your families are doing and what we can do to assist.
 
Air Science reabre miércoles, 13 de septiembre de 2017
Con el poder restaurado, nos complace anunciar que la fábrica y las oficinas de Air Science volverán a abrir el miércoles, 13 de septiembre de 2017.
Debido al huracán Irma, puede haber una respuesta retrasada en las peticiones de cotización. A medida que nuestro personal regrese de la evacuación, reduciremos la reserva. Todas las peticiones de cotización anteriores se han acumulado en nuestra cola y se procesan lo antes posible.
Comuníquese con nosotros en info@airscience.com como de costumbre; esta dirección será monitoreada continuamente.
Gracias por su comprensión a medida que nos recuperamos de la tormenta.
Atención a los empleados de Air Science
Tanto los turnos primero como segundo deben reportarse al trabajo en miércoles, 13 de septiembre de 2017, tan pronto como sea seguro para usted hacerlo. Contáctenos en los números proporcionados para hacernos saber cómo usted y sus familias están haciendo y qué podemos hacer para ayudar.
Due to Hurricane Irma, there may be a delayed response on quote requests. The Air Science office is open with staff on site as they return from evacuation. Please contact us at info@airscience.com as usual; this address will be monitored continuously. We thank you for your understanding as we recover from the storm.
Debido al huracán Irma, puede haber una respuesta retrasada en las peticiones de cotización. La oficina de Air Science está abierta con el personal en el sitio a medida que regresan de la evacuación. Comuníquese con nosotros en info@airscience.com como de costumbre; esta dirección será monitoreada continuamente. Gracias por su comprensión a medida que nos recuperamos de la tormenta.
We're back. At Air Science, our experience with Hurricane Irma was a challenge for all of us, both personally and professionally. Thankfully, we are back on the job and working hard to catch up.
While our quotations and administrative systems remained in operation during the storm, our manufacturing and shipping functions were temporarily suspended. These have now been restored.
On behalf of all of us at Air Science, we thank you for your thoughts and prayers, your patience and understanding, and most of all, your continued confidence in our company, our products and our services.
Paul Chambre
 
Estamos de vuelta. En Air Science, nuestra experiencia con el huracán Irma fue un reto para todos nosotros, tanto personal como profesionalmente. Afortunadamente, estamos de vuelta en el trabajo y trabajando duro para ponernos al día.
Mientras nuestros peticiones de cotización y sistemas administrativos permanecían en operación durante la tormenta, nuestras funciones de fabricación y envío se suspendieron temporalmente. Estos han sido restaurados.
En nombre de todos nosotros en Air Science, le agradecemos por sus pensamientos y oraciones, su paciencia y comprensión, y sobre todo su confianza continua en nuestra empresa, nuestros productos y nuestros servicios.
Paul Chambre
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Filtration Guide

Ductless fume hoods provide cost benefits over ducted systems by eliminating the need for ductwork changes in the laboratory as well as utility savings; however they are limited in the types of chemicals and the quantities of those chemicals that they can handle.  The purpose of this application guide is to provide information as to the proper use of the ductless fume hood.
 

Using the Ductless Fume Hood

 
The use of activated carbon filters in ductless mode is dependent on the chemicals being used and the quantity of chemical being evaporated into the filter.  Generally speaking, chemicals with a molecular weight over 30 and a boiling point higher than 60°C are candidates for adsorption with carbon filters, but there are exceptions and combinations which need to be evaluated by your supplier. 
 
Carbon filters have retention capacities which can be pre-determined and your supplier should be able to predict the amount of chemical in grams or ml capable of being retained by the filter prior to any measurable desorption taking place.  This is done by using data from the carbon supplier, testing under dynamic conditions, extrapolation from available data, and engineering judgment.
 

Carbon Filtration Technology

 
Our ductless fume cabinets incorporate our exclusive Multiplex™ high performance activated carbon filters, which is the primary filtration component in removing all chemical fumes from within our products before air is recirculated back to the laboratory.
 
Activated carbon exhibits excellent adsorbent characteristics that make carbon very useful for a wide variety of processes including filtration, purification, deodorization, decolorization, purification and separation.
 
The effectiveness of activated carbon as an adsorbent is attributed to its unique properties, including “large surface area, a high degree of surface reactivity, universal adsorption effect, and pore size".
 
Activated carbon is produced from a wide variety of carbon-rich raw materials, including wood, coal, peat, coconut shells, nut shells, bones and fruit stones. New materials are currently under investigation as sources for activated carbon.
 

The two primary types of activation are:

  • Chemical Activation
    • This technique is generally used for the activation of peat and wood based raw materials.
    • The raw material is impregnated with a strong dehydrating agent; typically phosphoric acid or zinc chloride mixed into a paste and then heated to temperatures of 500 - 800°C to activate the carbon.
    • The resultant activated carbon is washed, dried and ground to powder.
  • Steam Activation
    • This technique s generally used for the activation of coal and coconut shell raw material which is usually processed in a carbonized form.
    • Activation is carried out at temperatures of 800 - 1100°C in the presence of steam.
Filter Monitoring
There are two aspects to filter monitoring:
  • Checking the airflow to ensure the pre-filter is not clogged with dust
  • and checking the exhaust air for chemical contaminants to ensure the main filter has not reached the breakthrough point.
Airflow can be measured with an anemometer. There are a number of anemometer designs available including propeller, hot wire and vane anemometer. In addition, most ductless fume hoods are fitted with a low airflow alarm which indicates a low airflow situation as well as fan failure.
 
Air Science uses high-quality centrifugal fans to ensure that airflow is maintained even as the pre-filter airflow resistance increases. Filter monitoring should aim to detect the period of initial breakthrough and in all cases should warn the operator well before the permissible exposure level (PEL) is reached.
 
activated carbon filtration active filtration zone
 
Adsorption takes place in a filter bed in what is known as the active filter zone (represented above as dark saturated area). As the filter is used this active zone progressively moves up the filter bed until it approaches the top surface of the filter. At this point there is an initial breakthrough by the contaminant vapor(s), and thereafter the percentage of contaminant gas that escapes filtration increases.
 
Filter monitoring can be performed with gas detection tubes.  Most of the units have test ports allowing the use of this equipment in a zone immediately above the main filter.  The filter is challenged with a known chemical, and the concentration of this chemical in the exhaust air is measured with a suitable detection tube.  The safety of this process is enhanced by the use of safety back-up filters that prevent any contamination coming from the main filter from being recirculated into the work area.
 
Electronic filter saturation alarms which use special gas sensors are also available.  These alarms provides continuous monitoring and remove the need for manual testing. Such sensors are sensitive to a wide range of hydrocarbon contaminants used in the laboratory, with a detection sensitivity of a few parts per million (PPM).
 
For more information on ductless fume hood technology, visit ductless.com.
 



Carbon Filters from Air Science

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