Filters high-efficiency particulate

HEPA-filter (high-efficiency particulate and aerosol air filter)... 

Plutonium solutions that have a low activity (<3.7 x 10 Bq (1 mCi) or 10 mg of Pu) and that do not produce aerosols can be handled safely by a trained radiochemist in a laboratory fume hood with face velocity 125—150 linear feet per minute (38—45 m/min). Larger amounts of solutions, solutions that may produce aerosols, and plutonium compounds that are not air-sensitive are handled in glove boxes that ate maintained at a slight negative pressure, ca 0.1 kPa (0.001 atm, more precisely measured as 1.0—1.2 cm (0.35—0.50 in.) differential pressure on a water column) with respect to the surrounding laboratory pressure (176,179—181). This air is exhausted through high efficiency particulate (HEPA) filters. 

Beryllium oxides Baghouses or high-efficiency particulate air (HEPA) filters... 

The purpose of open unidirectional airflow benches is to protect products from particulate contaminants by creating a controlled environment. These benches are used, for example, in electronic, biological, pharmaceutical, and food industries. It should be mentioned that within pharmaceutical production, aseptic sterile processes must be carried out in a Class 100 environment (U.S. Federal Standard 209 E, Airborne Particulate Cleanliness Classes in Cleanrooms and Clean Zones). To avoid particle contamination in the bench, horizontal or vertical airflow with high-efficiency particulate air (HEPA)-filtered air is used. The air velocity is normally 0.4-0.5 ra s". Some examples of typical arrangements of open unidirectional airflow benches are shown in Fig. 10.51. 

Air filter A device that removes particulate matter from a gas flowing through it. These are classified as Absolute A high-efficiency particulate air filter that is at least 99.79% efficient in the removal of thermally generated mOnodisperse dioctylphthalate smoke particles with a diameter of 0.3 pm, also known as a HEPA filter. 

HEPA A high-efficiency particulate air filter designed to deal with particles below 1 pm with efficiencies... 

HEPA (high-efficiency particulate air) filters Also known as absolute filters, the large collection filter surface area provides a high collection efficiency for particulate matter. 

Where a high cleaning efficiency is required it is sound practice to install a filter of lower performance upstream to trap the larger particles and prolong the life of the more expensive High Efficiency Particulate (HEPA) Air Filter. Two filters of equal merit placed in series will not be materially more efficient than one. 

Small areas Small puddles of liquid can be contained by covering with absorbent material such as vermiculite, diatomaceous earth, clay, sponges, or towels. Place the absorbed material into containers lined with high-density polyethylene. Larger puddles can be collected using vacuum equipment made of materials inert to the released material and equipped with a high-efficiency particulate air (HEPA) filter and appropriate vapor filters. Wash the area with copious amounts of soap and water. Collect and containerize the rinseate. Ventilate the area to remove vapors. 

A number of conditions must be considered when selecting protective equipment for individuals at the scene of a release. For instances such as "anthrax" letters when the mechanism of release is known and it does not involve an aerosol generating device, then responders can use Level C with high-efficiency particulate air (HEPA) filters. 

High-efficiency particulate air filters can remove lightweight particles such as pollens, mold spores, and cat allergen, thereby reducing allergic respiratory symptoms. 

Bag filters are composed of woven material that intercepts small particles on the filter surface by impingement and electrostatic attraction. The efficiency of collection increases as the depth of the filter cake increases, making these filters highly efficient for small diameter, even sub-micron, particle size. Filters are periodically shaken or back-flushed to remove particulate accumulation. These filters are usually constructed of woven materials suitable for operation at low temperatures up to about 350°C. 

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