High-efficiency particulate air HEPA

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. 

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. 

Responders may use full facepiece respirator with a P100 filter or powered air-purifying respirator (PAPR) with high efficiency particulate air (HEPA) filters when it can be determined that ... 

Filter A High-Efficiency Particulate Air (HEPA) filter is at least 99.97 percent efficient in removing particles with a diameter of 0.3 microns. 

The costs associated with the PAT process will vary based on site-specific conditions and the costs of pozzolan additives, operating safety requirements, and labor. The estimated costs associated with the stabilization of fine-grained soils that do not require pretreatment and do not pose extreme handling hazards are between 30 and 50 per ton. For the stabilization of coarsegrained soils, costs were estimated between 40 and 60 per ton. Pretreatment, containment, and high-efficiency particulate air (HEPA) filtration would add to these cost estimates (D20799S, pp. 23, 24, 66). 

An air supply filtered through High-Efficiency Particulate Air (HEPA) filters under positive pressure regardless of whether flow is laminar or nonlaminar. 

Off-gas emissions from the modified baseline process MPF will pass through a separately fired afterburner maintained at a temperature of 2,000°F. The committee was told that the afterburner design is patterned after the successful afterburner operations at JACADS and TOCDF (Webster, 2000). The key design parameter for the afterburner is to have a one-second residence time at 2,000°F (CR E, 2000). Off-gas emissions then pass through the PAS, which includes high-efficiency particulate air (HEPA) and carbon filtration. Metal parts emerging from the MPF will be disposed of as scrap metal. 

Adjustments in the air source should be made to obtain a controlled flow of air within the tunnel and across the entrance and exit openings. Air must be particulate-free as it enters the tunnel area therefore, all high efficiency particulate air (HEPA) filters in the tunnel must be integrity tested and certified prior to validation studies. 

Wisthaler et al. (2005) used PTR-MS to examine the products formed when ozone reacted with the materials in a simulated aircraft cabin, including a loaded high-efficiency particulate air (HEPA) filter in the return air system. 

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