Who invented bfe

The particle concentrations and the size distributions of the tested samples can be estimated by exploiting the wide-range particle spectrometer WPS , which is the combination of three various instruments, called the differential mobility diameter DMA , the laser particle spectrometer LPS , and the condensation particle counter CPC. The illustration of the experimental setup is illustrated in Fig.

Where, the C u value, and the C d term, present aerosol, which is sampled before and after passing upstream and downstream through the specimen. Schematic illustration of filtering set up Konda et al. The particulate respirators such as N95 protect the wearer only against the particles not vapours or gases.

Therefore, the airborne biological agents e. The classified particulate filters are labelled as P1 low-efficiency filters , P2 medium efficiency filters or P3 high-efficiency filters Infection Prevention and Control Application, Rengasamy et al. This test assesses the ability of the masks and respirators to lessen the squirted synthetic blood or any splashed or sprayed fluid that can penetrate the outer layer of the mask and transfer through the inner part by changing the pressure.

According to the ASTM F protocol, the penetration resistance ability of the medical face mask is estimated using the high-velocity synthetic blood, which is in contact with the surface of the test sample including a fixed volume in a specific time between 0 s and 2. Several factors have a strong effect on the penetration and the wetting of the body fluids including, polarity, viscosity, and the surface tension, the structure, and the relative hydrophobicity or hydrophilicity of the face mask material ISO, The hospitals contain different sources of the heat, oxygen, and fuel, the ASTM F standards requires a test regarding the flame resistance for all the medical masks.

The used material for masks and respirators should not present any hazards for the users, and their flammability shall not be high. The flammability factor is determined based on the 16 CFR part for clothing textiles U. CPSC, The flame spread test calculates the required time for the flame to reach the mask material in 5 in. Table 5 summarizes the characteristics of each class of materials that are categorized based on the 16 CFR part testing requirements U.

Classifications of face mask materials according to the flam resistance test U. The differential pressure test is an indicator of airflow resistance of the masks as well as their comfort and breathability Lord, During this test, airflow passes through the mask in a controlled manner, and the various pressures are calculated for the inner and outer layers of the mask.

The differential value is divided by the surface area cm 2 of the mask to estimate the breathability, where the higher Delta P values indicated a harder breath for the users. The Delta P values less than 0. CLK Medical Supply. The masks and respirator devices are worn by the wearer in high hazard environments. Thus, to increase the effectiveness of the devices, the wearers shall know how to use the devices correctly.

The fit test aims to check and avoid any leakage existence before using the masks or respirators Kiersma, The purpose of fit testing is to provide a perfect fit and appropriate seal for all tight facemasks and respirator facepieces, which can be done through two main methods. The first fit method is carried on utilizing either qualitative fit test methods or through the quantitative fit test techniques Coffey et al. In the basis of the control of substances hazardous to health COSHH Health and Safety Executive, protocols, there are different conditions in which the fit testing shall be repeated.

These conditions are including a the wearer has gained or lost weight, b the wearer has experienced any dental work, c the wearer has faced any imperfections such as scars, moles, etc. Tuberculosis Fig. Illustration of how to put on the well-fit of the FFP3 respirators a-e , as well as their fit check f.

Besides, the design of the respirator affects the fit of the facepieces as fitting a half-facepiece respirators, which only cover the mouth and nose, is more difficult compared to that of full-facepiece respirators which also cover the eyes Loeb, As was already mentioned, the fit-test for respiratory facepieces is mainly categorized into two groups, a qualitative, and b quantitative, that each can be done through different methods, which are summarized in Fig.

For the qualitative test, a hood and a taste or odour solution are utilized to investigate the capability of the wearer to smell or taste the sample. Furthermore, a quantitative method utilizes an instrument to calculate the efficiency of the respirator numerically using electronic equipment, which calculates the air leakage into the face masks Infection Prevention and Control Application, During the experiments through the fit testing methods, The fit factor can be obtained by using Eq.

The overall fit factor can be calculated using the harmonic mean value of each exercise Sietsema and Brosseau, If the N95 face mask is well fitted, it has the ability to filter out the small size particles less than 0. Face mask and respirators are to become and integral part of day to day life with the COVID pandemic.

PPE undergoes analysis for a variety of tests to evaluate their performance and suitability for different environments. Face mask and respirators each have different standards to be met with respirators having the higher of the two. Particulate filtration, bacterial filtration viral filtration and NaCL method are evaluated to ascertain their efficiency in the filtration of each of the named bodies.

Particulate filtration is measured using 0. Viral efficiency examines the assigned protection factor; this evaluates the face mask and respirators ability to reduce exposure to a virus in workplace conditions. The masks are further tested for their fluid and flame resistance, differential pressure and fit testing. Fluid resistance examines the penetration of and wetting of fluids on the mask, with bodily fluids, synthetic blood and saliva being measure. Flame resistance examines the flammability of materials used in masks, how much and how long the material will burn and how quickly the flame will spread.

Differential pressure is used to measure the comfort and breathability of the masks and airflow resistance, the higher the differential pressure, the harder it is to breathe in the mask.

Facepiece Fit Testing examines both qualitative and quantitative methods, with negative or positive pressure methods to study how well the mask or respirator fits on an individual face. By using all of these standards and their testing methods face masks and respirators can be approved for use in the prevention of the spread of COVID National Center for Biotechnology Information , U.

Saf Sci. Published online Sep Author information Article notes Copyright and License information Disclaimer. Received Jul 21; Accepted Sep 7.

Elsevier hereby grants permission to make all its COVIDrelated research that is available on the COVID resource centre - including this research content - immediately available in PubMed Central and other publicly funded repositories, such as the WHO COVID database with rights for unrestricted research re-use and analyses in any form or by any means with acknowledgement of the original source. This article has been cited by other articles in PMC. Graphical abstract. Open in a separate window.

Table 1 Different mask types and materials used in construction Hall, Mask type Materials Tie-on Surgical Face Mask 3-ply, pleated rayon outer web with polypropylene inner web Classical surgical Mask, Blue 3-ply, pleated cellulose polypropylene, polyester Sofloop Extra Protection Mask 3-ply, pleated blended cellulosic fibers with polypropylene and polyester, ethylene methyl acrylate strip Aseptex Fluid Resistant Molded rayon and polypropylene blend with acrylic binder Surgine II Cone Mask Molded polypropylene and polyester with cellulose fibers Surgical Grade Con Style Mask Molded polypropylene.

Personal protective equipment PPE testing methods Different PPE tests are utilized to guarantee the security and the safety of the PPE manufacturers in possibly hazardous workplace environments.

Table 2 Specific types of PPE testing. Type Protective ensemble testing For example, testing for vapour, chemical, or liquid splash resistance of clothing ensembles, and full-body protection systems ASTM F S. Type Impact protection testing In the case of sports helmets and occupational headwear and body protection equipment.

Illustration of the common test to estimate the performance of face masks. Viral filtration efficiency VFE The virions, as one of the smallest bioaerosol particles with a size diameter of 20— nm, can simply enter through the respiratory organ and result in various epidemic infections. SM: Surgical mask. Fluid resistance This test assesses the ability of the masks and respirators to lessen the squirted synthetic blood or any splashed or sprayed fluid that can penetrate the outer layer of the mask and transfer through the inner part by changing the pressure.

Flame resistance The hospitals contain different sources of the heat, oxygen, and fuel, the ASTM F standards requires a test regarding the flame resistance for all the medical masks. Table 5 Classifications of face mask materials according to the flam resistance test U. Differential pressure Delta-P The differential pressure test is an indicator of airflow resistance of the masks as well as their comfort and breathability Lord, Facepiece fit testing The masks and respirator devices are worn by the wearer in high hazard environments.

Respirators and Surgical Masks: A Comparison, pp. Anfinrud P. Visualizing speech-generated oral fluid droplets with laser light scattering. New Engl. ASTM F, Standard test method for evaluating the bacterial filtration efficiency BFE of medical face mask materials, using a biological aerosol of Staphylococcus aureus. American Society for Testing and Materials. ASTM International, Spain tightens mask rules for all older than five. Google Search. Borkow G. A novel anti-influenza copper oxide containing respiratory face mask.

PLoS One. Respiratory protective devices— Methods of test. Part 7: Determination of particle filter penetration. Bs En Chatterjee, P. Comparison of five methods for fit-testing N95 filtering-facepiece respirators. Fadare O.

Covid face masks: a potential source of microplastic fibers in the environment. Total Environ. Hall, D. Han Z. Characterizations of particle size distribution of the droplets exhaled by sneeze.

Huang H. COVID a call for physical scientists and engineers. ACS Nano. June, Infection prevention and control during health care when novel coronavirus nCoV infection is suspected, ISO, Juang P.

Emergency forum N95 respirator cleaning and reuse methods proposed by the inventor of the N95 mask material. Occupational Safety and Health Administration. In: Encyclopedia of Toxicology: third ed. Konda A. Aerosol filtration efficiency of common fabrics used in respiratory cloth masks.

A new approach to measure the resistance of fabric to liquid and viral penetration. The cultural origin of the original fictional town the famous "squeal like a pig" scene was lost, but the idea of backward sodomites in a foreign world survived the translation. As for the abbreviation, well, that's something that tends to happen quickly in the world of SMS and tweets.

If something occurs frequently and requires more than a couple of characters, somebody is going to abbreviate it.

I don't have an better explanation than Stan for the "butt-fuck" part I'd always heard it as "bum-fuck", which made me think it was originally British but it certainly ante-dates the First Gulf War.

Wikipedia suggests that "Egypt" was originally a Chicago-area expression referring to the southern third of Illinois , especially the towns of Cairo, Thebes, and Karnak. I know for certain we used "BFE" when I was back in high school too prior to and therefore, well before even the first Gulf War.

It was immediately likened to what they called the "midwestern" expression "BFE". Basically, if one was hopelessly lost, it was said they were "up in Poughkeepsie. Historically, as it was explained, New York City mobsters, criminals, etc. This notion of this tradition is apparently still popular today, as it was duplicated, more or less, in a later episode of the Sopranos.

As previously suggested, the vulgarity and the proximity to Chicago of Cairo, Thebes, and Karnak, Illinois would lend some creedence to the Wikipedia suggestion that the "BFE" expression might have similarly arose among mobsters, criminals, or anyone looking to "hide out" outside the Chicago area. It seems very logical to think that if a mobster, etc. Louis and hiding out across the river in southern Illinois. Something else that lends some creedence to this suggestion is that if one proceeds to the very tip of southern Illinois and ultimately crosses the Ohio River, one would end up in Paducah Podunk , Kentucky.

Paducah is miles from Chicago, miles from St. When I was working in the oil patch in Wyoming in the early 's we used the term BFE to refer to any remote location we had to go to work. Example: "Where did you go today?

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Ask Question. Asked 10 years, 8 months ago. Active 8 years, 11 months ago. Viewed k times. Improve this question. Hugo Scott Mitchell Scott Mitchell 4, 9 9 gold badges 30 30 silver badges 44 44 bronze badges. A related destination, at least in my mind, was always East Jesus, which I first encountered mid 90s. Some language and stories emphasize the forlornness of a place by implying that it's so far from civilization that there are no women around, so men have to deviate from personal norms to achieve sexual satisfaction.

So in this instance, this is a corner of Egypt so remote that the only option is to fuck your comrade in the bum.

Add a comment. Active Oldest Votes. Improve this answer. Hugo Hugo I was in the military during Gulf War I -- trust me, the hate and propaganda was thick in the air, and it wasn't all about Iraq.

Just because there was anti-Arab sentiment then doesn't mean that that's when the phrase originated.