Large quantities of submicron particles (0.1-0.5 m) and ultrafine particles (0.1 m) are produced at manufacturing facilities during processes such as welding, casting, and asphalt production.
Occupational Asphalt Face Piece
In this article, we are going to discuss how face piece can help occupational asphalt workers with lung cancer and it goes a long way indeed. Despite having much smaller cumulative masses than larger particles, their greater penetration into the human lower respiratory tract, larger surface area, and ability to pass through the respiratory epithelial layers have resulted in more severe health effects. This study looks at the effectiveness of two commonly used N95 filtering facepieces and N95 pleated particulate respirator models against ultrafine and submicron particles. The N95 filtering facepiece and N95 pleated particulate models were tested on a manikin in both sealed and unsealed conditions at a variety of industrial and academic testing sites, including a foundry, a welding site, and an asphalt manufacturing facility. Two TSI Nanoscan SMPS nanoparticle counters were used simultaneously to collect data on particles ranging in size from 10 to 420 nm from both inside and outside the respirators. One represented the exposure levels at work, while the other considered the exposure after it had been filtered through the respiratory surfaces. According to the findings, the majority of the particles produced by these manufacturing processes were between 40 and 200 nm in size. 
Despite particle size variations, the percentage of filtration levels for both N95 respirator models in sealed conditions, as well as the N95 pleated particulate model in unsealed conditions, remained mostly within the desired protection level of 95%, according to the results. In the N95 filtering facepiece model, unsealed respirators demonstrated a very high penetration percentage, lowering protection levels to 60% in some cases. The concentrations of airborne particles in the workplace varied significantly, but the filtration rates remained relatively constant. The term "ultrafine particle" refers to a matter particulate with a size of 1 to 100 nanometers that are typically produced naturally or through engineering techniques. Natural occurrences like forest fires or industrial combustion processes both release ultrafine particles. Ultrafine particles that occur naturally include ash, viruses, and smoke. Engineered ultrafine particles are produced during processes such as asphalt and concrete mixing, welding, cosmetics manufacturing, and others. Because of their small size, ultrafine particles are often overlooked despite their harmful effects in the workplace. The Brownian Motion theory states that the motion of ultrafine particles is random and characterized by frequent collisions that result in high momentum values. Because of their unpredictable nature, behavior analysis and control of the effects on human health have become increasingly difficult. Numerous studies have been conducted to evaluate and comprehend the nature and behavior of ultrafine particles. It has been discovered that ultrafine particles are highly concentrated in environments with welding fumes. Given that metal-rich particles present in fume composition are hazardous to humans, the conclusion is extremely pertinent. Schraufnagel has thoroughly examined the health effects of ultrafine particles. According to this review, it is critical to understand how the material, mass, size, and surface of ultrafine particles affect human health. There have been reports of significant relationships between particle size, surface, and heart and lung complications caused by inhaling particles. Because of their large particle surface area carrying significant amounts of absorbed pollutants, ultrafine particles are thought to be more toxic than fine or coarse particles, potentially increasing mortality due to particle interaction. 
Face Mask Occupational Asphalt
There haven't been many studies on how well air filters and face masks work at removing ultrafine particles. Despite face piece respirators and filters having strict regulations for micro and others, during occupational asphalt larger-sized particles, current protection, and filtration devices do not have standards for preventing the ingestion of ultrafine particles. Ultrafine particle concentrations are frequently highest in metal industries, machine shops, and welding shops. Inhaling these ultrafine particles has been linked to health risks such as inflammation and toxicity, with studies showing that these risks are more dependent on the specific surface area than the total mass. Because ultrafine particles have a larger relative surface area than larger particles, they pose a greater risk to human health. Furthermore, because they are smaller, they can penetrate deeper into the human lower respiratory tract and are more difficult to filter out. It is critical to understand how these particles behave. It has been shown that ultrafine particles have a greater potential to cause an inflammatory response than more typical fine particles. As a result, understanding how ultrafine particles are removed from processes such as welding is critical. Ready-mix concrete (RMC), one of the most important subsectors in modern construction, is in charge of producing building materials required for the construction of large engineering structures such as roads, bridges, homes, and high-rises. RMC is made by combining fine and coarse aggregates with cement and water. 
RMC has many advantages, including quick construction due to computer-programmed delivery on site, consistency of quality due to accurate computerized control of sand aggregates and water as per mix designs, ability to minimize cement wastage due to bulk handling, labor cost savings, and raw material economy. Despite being the world leader in RMC production, with over 5000 plants and 68,500 trucks, the US RMC industry continues to face safety issues. Workplace safety concerns are linked to a variety of activities performed in an RMC plant that necessitate the use of tools and the operation of machines, such as mixers, cement batchers, aggregate batchers, conveyors, radial stackers, aggregate bins, cement bins, heaters, chillers, and cement silos. Because they are partially carried out in the production area, where RMC is made and loaded into mixer trucks, these activities expose RMC employees to a variety of safety risks. Workers may experience eye, skin, and respiratory tract irritation, overexertion and awkward postures (ergonomics), slips, trips, and falls, chemical burns from wet concrete, loss of stability, cutting, and severing risks, and dangers caused by vibration and radiation as a result of cement dust exposure. The most common sources of these hazards are inadequate lockout/tag-out systems on machinery (mechanical and electrical hazards), ejection of parts or material, shearing hazards caused by noise, stabbing, puncture, friction, abrasion, high-pressure fluid injection, or combined hazards. Because RMC's concrete contains between 10% and 20% silica, some of its projects may expose workers to silica. RMC contains silica, which becomes airborne during jackhammering operations. Silicosis is a debilitating, irreversible, and occasionally fatal lung disease caused by prolonged inhalation of respirable crystalline silica. Over one million American workers are exposed to crystalline silica each year, and more than 250 people die from silicosis. The disease has no known cure, but it can be completely avoided if employers, employees, and healthcare professionals work together to limit exposure. To reduce the risk of silica exposure, it is recommended that safe working conditions, adequate dust cleaning, and ventilation of working areas be provided. The power plant's loading procedure exposes RMC plant workers to cement-containing dust. Through their skin, operators may come into contact with irritant-containing concrete mixtures and additives. Cement products are inherently hazardous. Wet concrete has been shown to react with skin, natural moisture, and the mucus layers of the eyes. Furthermore, concrete contains a chrome component, which is a strong irritant. These substances have the potential to irritate the skin and cause allergic reactions. According to OSHA, the concrete industry employs over 250,000 people in the United States. Tens of thousands of the hundreds of thousands of concrete product workers have sadly died as a result of an occupational disease, injury, or death. Approximately 28,000 of those workers, or more than 10%, were injured or ill at work, and 42 died in just one year. According to Bureau of Labor Statistics data from 2013, the injury rate in the RMC sector was 4.8. There was a lack of a comprehensive analysis of the risks and hazards that could arise during the production and handling of RMC. Manuals and guidelines published by organizations such as OSHA, ACPA, and NSCSA are the only resources available to raise RMC producers' awareness of safety. RMC occupational health and safety field research is still lacking. 
Face Mask Respirator
Numerous studies have been conducted on the environmental effects of welding. Cho et al. use aerosol to evaluate the efficacy of various particulate respirators. Even studies on potential face mask respirator leaks have shown that the effectiveness of the filter is dependent on particle size. Extensive review studies on the effectiveness of commonly used N95 respirators have recently been published. A hygiene database of exposure has also been developed to track the overall cumulative health effects of asphalt industry workers. This study measured and compared exposure levels to ultrafine particles before and after filtration through a facepiece filter during welding activities and routine asphalt plant operations. Filters, including N95 pleated particulate respirator models and commercially available N95 filtering facepieces, were used in both sealed and unsealed situations. Stick welding, MIG welding, and die casting sites were investigated. To simulate a welder's exposure levels, measurements were taken from a distance of about 1 m and a distance of about 2-3 m from the welding spot. We used two 3910 NanoScan SMPS Nanoparticle Sizers at the same time. One NanoScan measured nanoparticle exposure levels prior to filtration, while the other NanoScan measured exposure levels after filtration. This study compares the protection provided by two commercially available facepieces against submicron and ultrafine particles during various manufacturing processes. A field-compatible testing setup was developed to allow for the parallel evaluation of respirators at various testing locations while collecting air samples to assess the respirators' effectiveness in filtering contaminants. Two of the current authors used a similar set-up to evaluate the N95 facepiece on construction sites. The setup included two NanoScan SMPS ultrafine particle monitors (model: 3910, manufacturer: TSI). These nanoparticle scanning devices have a scan time of 60 seconds and inhale and analyze 1 cubic centimeter of air each time. The scanner detects particles with sizes ranging from 10 nm to 420 nm. After that, the particles are divided into 13 logarithmically scaled bin sizes. The median values for these 13 bin sizes are 11.5, 15.4, 20.5, 27.4, 36.5, 48.7, 64.9, 86.6, 115.5, 154, 205.4, 273.8, and 365.2 nm. Every minute, it happens again. As a result, a ten-minute test consists of ten cycles with ten data points for each bin. For each location and set of parameters, at least ten of these data points are collected. The effectiveness of ultrafine particle and submicron particle filtration by standard worker respirators was investigated in two work environments with high potential for ultrafine particle concentrations, such as welding work sites and workshops and asphalt plants. The setup included: Two NanoScan SMPS 3910 devices were used to assess ultrafine particle concentration; Three sampling probes that maintain airflow; N95 respirators are used to test the effectiveness of ultrafine particle filtration. A manikin head made of foam to represent how people would interact with their surroundings; An 85 L/min air pump is used to simulate human breathing effects. A portable stand and cart for transporting the testing setup between locations The set-up was used on construction sites to simulate a construction worker's exposure to ultrafine particles. It is worth noting that the data collection process required the use of two NanoScan SMPS 3910s at the same time. One device measured unfiltered upstream airflow outside of the respirator. The downstream airflow of the respirator was measured simultaneously by the other device. To simulate airflow, an 85 L/min air pump was used, drawing a comparable volume of air into the respirator as a human would when breathing normally. According to the National Institute for Occupational Safety and Health (US NIOSH) N95 Filtering Facepiece Respirator (FFR) certification method, an N95 FFR sealed onto a plate should be tested against an airflow of 85 L/min. As a result, we incorporated this airflow into our experimental design. The setup was designed to be portable, allowing it to be moved from one location to another and transported to multiple locations within a single space. As a result, a utility cart with an integrated stand was designed to hold the two NanoScan units as well as the adjustable-height manikin heads. 