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Cutting fluid has cooling and lubricating properties and is an important part of the field of metal machining. Owing to harmful additives, base oils with poor biodegradability, defects in processing methods, and unreasonable emissions of waste cutting fluids, cutting fluids have serious pollution problems, which pose challenges to global carbon emissions laws and regulations. However, the current research on cutting fluid and its circulating purification technique lacks systematic review papers to provide scientific technical guidance for actual production. In this study, the key scientific issues in the research achievements of eco-friendly cutting fluid and waste fluid treatment are clarified. First, the preparation and mechanism of organic additives are summarized, and the influence of the physical and chemical properties of vegetable base oils on lubricating properties is analyzed. Then, the process characteristics of cutting fluid reduction supply methods are systematically evaluated. Second, the treatment of oil mist and miscellaneous oil, the removal mechanism and approach of microorganisms, and the design principles of integrated recycling equipment are outlined. The conclusion is concluded that the synergistic effect of organic additives, biodegradable vegetable base oils and recycling purification effectively reduces the environmental pollution of cutting fluids. Finally, in view of the limitations of the cutting fluid and its circulating purification technique, the prospects of amino acid additive development, self-adapting jet parameter supply system, matching mechanism between processing conditions and cutting fluid are put forward, which provides the basis and support for the engineering application and development of cutting fluid and its circulating purification.

The use of metalworking fluids during machining can generate oil mist and endanger the health of workers. In order to study the characteristics and emission laws of oil mist generated by machining, this study constructed a test bench to simulate the turning process. Parameters affecting the oil mist generated in the minimum quantity lubrication (MQL) mode and flood cooling mode were studied by means of single-factor experiments, and the formation mechanisms of oil mist were analyzed. The results show that the oil mist generated by the MQL system has two main sources, the initial escape of oil mist into the air and the evaporation/condensation of oil mist. The centrifugation has almost no effect on oil mist formation in the MQL mode. The mass concentration of oil mist generated by the MQL system is proportional to the cutting oil flow rate. When the work-piece is at room temperature, increasing the air supply pressure and nozzle distance, increases the oil mist mass concentration. For the flood cooling mode, the concentration of centrifugal aerosol is linearly and positively correlated with the relative centrifugal force generated by the work-piece, and the coefficient of determination (R2) is above 0.97. The oil mist mass concentrations in MQL mode is 8.33 mg/m3~ 305.88 mg/m3. The MMD and SMD are 0.74 µm to 4.42 µm and 0.31 µm to 2.14 µm, respectively. The oil mist mass concentrations in flood cooling mode is 0.2 mg/m3~ 22.42 mg/m3. The MMD and SMD are 1.81 µm to 6.58 µm and 0.45 µm to 5.13 µm, respectively.

Oil separation is commonly needed in air conditioning and refrigeration systems to reduce the oil circulation rate and keep the oil inside the compressor. For compactness, the oil separation structure integrated into the compressor is more and more popular than traditional external oil separators. However, a quantitative guideline for the design of oil separation structure is missing for irregular geometry and realistic flow condition at the compressor discharge. This paper presents impinging separation mechanism, one of the basic mechanisms of droplet separation. The separating structures are studied by flow visualization and experimental measurement under realistic compressor discharge conditions. The video of oil mist flowing through the baffles and plates is captured by a high-speed camera and analyzed quantitatively. The effect of the oil flow condition and the effect of separator geometry design are investigated based on the experimental data. With the help of flow visualization, the flow details are analyzed, and a semi-empirical model is proposed to predict the separation efficiency and pressure drop of a certain wave-plates structure. The results and conclusions from this study give useful guidelines about how to reduce the oil circulation ratio by designing oil separators.

This article presents paraffin oil mist penetration tests of commercially available air-purifying respirators of different construction conducted using the method described by Standard No. ISO 16900-3:2012, which incorporates flow rates (up to 255 l/min) of test aerosol. The testing method reflects differences in work intensity during the use of respirators. Moreover, the experimental stand, designed according to the international specifications, is described. The results show that the higher the paraffin oil mist flow rate, the higher the penetration index, irrespective of the testing method used and the type of respirator investigated. While at high flow rates, filtering half masks of the first protection class (FFP1) met the requirements of their protection class according to European Standard No. EN 149:20001+A1:2009, filtering half masks of the second and the third protection class (FFP2 and FFP3) did not.

Introduction: Once a submarine dives, the captive atmosphere inside keeps changing due to release of various pollutant gases. The gases are produced by machinery, cooking, human, paints, batteries, cooking etc. The study was envisaged to measure these gaseous pollutants on surface and in prolonged dive onboard EKM and SSK class submarines. Methods and Material: Detector tubes and pumps were used to measure the concentration of twenty gaseous pollutants in harbour on surface & during sailing in dived condition. In harbour, readings were taken early morning and before secure in the evening. During sailing readings were taken on surface, just after diving and thereafter every four hrs. The readings were recorded in excel sheet and correlated with activities on board at time of taking reading. Results: Only Ammonia and Hydrogen Sulphide were detected at the beginning of the day in harbour, however by the end of the day all other gases were detected except Mercury, Oil mist, Nitrogen Dioxide, Ozone & Arsine. At Sea none of the gases were detected at the beginning of sailing. At 12h post dive all gases were detected except Mercury, Oil mist, Nitrogen Dioxide, Ozone, Halogenated Hydrocarbons & Arsine. Recommendations and Conclusion: The gas concentration values obtained by using detector tubes and pumps were found to be within recommended Permitted Exposure Levels (PEL) for human for continuous exposure. No gas was found to be above the recommended PEL. There was no significant difference in the gas concentration levels in the EKM & SSK Class submarines. Pump and detector tube is a convenient, reasonably accurate and efficient method to measure gaseous pollutants on board Submarines.

Similar to fine dust, liquid aerosols represent a risk to human health since small droplets may enter the respiratory system and cause health problems or severe diseases, such as COVID-19. Oil mist emissions from production processes and from air brakes are reduced by filters and by air dryer cartridges, respectively, while virus-like aerosols are removed by face-masks. Since the two-phase flow processes involved are highly complex and occur on vastly different scales ranging from the scale of single droplets and fibers up to the scale of a whole filter or face mask, the modeling and simulation is extremely challenging. In this work, we present a macro-scale approach for modeling and simulation of the two-phase flow processes in fibrous filters which allows predicting both pressure loss and filtration efficiency from new to steady-state where material parameters and constitutive relationships are obtained based on nano CT scans and micro-scale simulations. Compared to previous work, this approach starts from a physical basis as it relies on mass and momentum conservation and is then closed by material laws. Using this macro-scale approach it is found that both pressure loss and oil mass at steady-state are in good agreement with experimental findings.

Oil mist detector is an important equipment in the early stage of the explosion of the crankcase for marine engine, and the oil mist detection module determines the working performance of the oil mist detector. By means of infrared light transmission principle, method and compositions of the detection module was extracted. Through analyzing the safety and reliability of hardware circuit module, real-time and accuracy of detector, overall scheme design of oil mist detection module was carried out. By analysis of principle and detection method oil mist, power and photoelectric conversion modules were designed and developed. Finally, laboratory verification of oil mist detection module was conducted, experimental results showed the module satisfied the design and function requirements.

Oil mist leakage is quite dangerous to the health of the staff as well as for the safe functioning of hydro generators. In this study, a model was established based on flow theory analysis. Three-d...

Metalworking fluids used in industrial workshops may present a major threat to the health of workers who have been exposed to a high oil mist concentration over a long period of time. Therefore, monitoring the temporal and spatial distribution of particulate matter concentration has great practical significance for the control of oil mist. Traditional particle monitors are generally cumbersome, expensive, and difficult to maintain, which to some extent restricts their extensive use in workshops. Recent years have witnessed tremendous developments in the area of low-cost sensors, which are of great help in obtaining high-density pollution data. In this paper, we evaluate the performance of an inexpensive laser sensor (A4-CG) during long-term oil mist monitoring in a machine shop for the first time. With the use of Lora technology, we developed an online oil mist monitoring network to access real-time concentration, temperature, and humidity information from distributed monitors. According to the results, the sensor data correlated well with measurements by the reference instrument (R2 = 0.96), which means that the distributed sensor network can accurately detect the concentration level of oil mist in the workshop. In fact, most of the sensors demonstrated stable operation for up to half a year according to cluster analysis, while several sensors exhibited serious data drift. Furthermore, the results indicate that the peak oil mist concentration in most areas during production exceeded the value of 0.5 mg m-3 recommended by NIOSH, and it was found that appropriately lowering the relative humidity can make sampling more accurate, while lowering the temperature can reduce the oil mist concentration in the workshop. Thus, measures to control oil mist such as generation and distribution of pollution sources should be on the agenda.

Oil is important to compressors, but it brings some side effects on the performance of refrigeration systems. Discharge valve or orifice in the compressor plenum is the gateway for the oil to leave the compressor and circulate in the system. The space of the compressor plenum has the potential to separate the oil mist from the refrigerant so that oil circulation ratio (OCR) is reduced. In this study, the formation, distribution, and movement of oil droplets in the plenum are investigated through visualization and CFD simulation. Videos of oil atomization are captured by the high-speed camera to describe how oil mist is formed. The distribution of droplet size and velocity is quantified by video processing techniques. Discrete phase model gives the numerical approach to study the oil droplet movement inside the compressor plenum. The numerical simulation is verified by comparing visualization results with simulation results. The oil flow phenomenon and its quantification provide important information for the design of separation structure incorporated in the compressor. Also, a set of tools are developed and verified to study the oil droplets behavior in different types of compressor plenums.

In industrial units, EFD maps are used as suitable methods for optimal management and controlling the release of pollutants into the environment. Hence, the main objective of the present research was to obtain the Environmental Flow Diagram-Air Pollutants (EFD-AP) map of the Purified Terephthalic Acid Production Units (PTA) of petrochemical industries. To this end, the flow of materials, feed, and productions of a PTA production unit in the southwest of Iran was analyzed. The pollutants of all 7 process sources and 2 combustion sources were sampled and measured using standard procedures. Finally, according to the results some calculations were done to determine the APs emission factors of the sources, and the EFD-AP maps of the studied unit were prepared. Results showed that the total emission factors of the Acetic acid, Methyl acetate, PTA powder, oil mist, CO, NO, NOx, CxHy, Co, Mg, Cu, Ni, Cd, Ti, Mo, Cr, and Pb were 219.518, 1.912, 44.58, 0.888, 64201.211, 1982.094, 2091.858, 23082, 76.868, 0.0193, 15.102, 36.829, 2.914, 37.623, 15.367, 200.572, and 2.888 mg per tonne of PTA, respectively. Also, results revealed that process sources emit different toxic and criteria pollutants into ambient air, while combustion emission sources (S8: hot oil furnace, S9; incinerator) have the main role in releasing criteria air pollutants, toxic trace elements and GHGs. It should be noted that emission factor of GHGs (CO2) for selected PTA unit was equal to 54661355 mg per ton of PTA production. Therefore, EFD-AP maps used for prioritization, controlling and management of APs emissions. Moreover, these maps have main role for preparing industrial atmospheric emission control action plan.

Oil mist particles emitted in industrial buildings are harmful to health. To evaluate the control effect of existing ventilation strategies on oil mist particles, this work conducts field investigations on the processing workshops of different scales and processes. Through on-site measurements, the basic characteristics of the mass concentration, quantity concentration, particle size distribution, processing technology, and emission rate of oil mist particles can be learned from different angles. The article presents the concept of unit emission rate index, which can provide reference data for ventilation design, as well as input parameters for simulation calculation. At the same time, based on the air change rate, the effect of controlling oil mist particles was evaluated, and the relationship between the air change rate and the concentration of the workshop was investigated. In view of the uniformity of the oil mist concentration in the workshop, the influence of the process emission rate and the ventilation mode on the mass concentration of oil mist particles was discussed. The conclusions obtained can be used as data support for optimizing ventilation strategies to control oil mist pollution and play a certain guiding role in the ventilation design and evaluation of industrial buildings.

The aim of this experimental study is to investigate the separation performances of a new set of small cyclones. The diameter of these cyclones spans the range of 20–45 mm, which is the typical size of these devices when they are used for separating oil mist from blow-by gases in internal combustion engines. To reproduce the flow rates and oil load of combustion engines, we developed a flow bench, with a polydisperse aerosol generator producing engine oil droplets with diameter in a 0.3–10 µm range. Measurements of the aerosol particle concentrations upstream and downstream of the cyclone permitted the determination of the particle collection efficiency, for the six devices that were tested, with flow rates ranging from 20 to 200 Nl/min which are typical operating conditions. For the six cyclones, the geometry is normalized and all internal dimensions within the cyclone are proportional to its diameter. With the operating conditions of this study, the annular Reynolds number varied in the range 1.27×10 3 to 12.2×10 3 . From the measured fractional collection efficiency curves, dimensionless cut-off aerodynamic diameters were determined. These measurements have been compared with available correlations for the determination of this dimensionless diameter as a function of the annular Reynolds number. Different correlations are proposed in this study, for the evaluation of the cut-off diameter and for the shape of the collection efficiency. We were able to establish that the collection efficiency curve dimensionless slope is correlated to a Reynolds number.

As a more efficient and advanced technology, adapting oil mist lubrication system as the leading lubricating plan has become a trend in enterprises. This paper summarizes and discusses the development of oil mist lubrication system and key technologies of it. At the same time, in order to solve the residual fog overflow problem of oil mist lubrication system, the various methods of residual fog recovery are summarized and discussed. Meanwhile, the future direction about the development of residual fog recovery system is prospected based on the current situation.

The exposure for workers handling and recycling offshore drilling waste are previously not described, and given the potential for exposure to hazardous components, there is a need for characterizing this occupational exposure. In this study five plants recycling offshore drilling waste with different techniques were included. Measurements were conducted in both winter and summer to include seasonal exposure variations. Altogether >200 personal air-exposure measurements for oil mist, oil vapor, volatile organic compounds (VOC), hydrogen sulfide (H2S) and solvents were carried out respectively. Microorganisms related to drilling waste were identified in bulk samples and in stationary air measurements from two of the plants. The exposure to oil mist and oil vapor were below 10% of the current Norwegian occupational exposure limits (OEL) for all measured components. The plants using the Resoil or TCC method had a statistically significant higher exposure to oil vapor than the plant using complete combustion (p-value

The oxidative potential (OP) measures the ability of pollutants to oxidize a chemical/biological probe. Such assays are starting to gain acceptance as integrative exposure metrics associated with inflammatory-based pathologies. Diseases such as asthma, rhinitis or cancers are reported for workers exposed to oil mist, which are aerosols of metal working fluids (MWF) emitted during the machining of metals. Measuring oil mist in the air is challenging, and exposures are often quantified as the mass fraction, which does not account for exposures to the gaseous fraction. Consequently, exposures are underestimated and furthermore, the hazardous property of oil mist is not assessed. We postulate that it is more relevant to assess occupational exposures to the hazardous fractions of oil mist by measuring OP than by simply measuring mass. We characterized exposures to straight and water-based MWF among workers in the French and Swiss mechanical industry using standard methods for oil mist and the ferrous orange xylenol assay for OP assessment (OPFOX). Considering the particulate fraction, the water-based MWF presented the greatest OPFOX. The OP was associated with organic carbon and iron content. The gaseous fraction of the oil mist presented also an important redox activity, particularly in workshops where straight oils were used. The hexanal concentration was associated with this OPFOX. The OPFOX measurement is thus integrative of multiple parameters, and bring complementary information when assessing MWF exposures. Our results highlight that OPFOX account for MWF type and could be an interesting parameter to characterize such exposure.

Internal gas velocity fluctuations and their effects on the mist diffusion process were examined in a long horizontal pipe to understand oil mist transportation, particularly in the laminar-to-turbulent flow transition region. Three hot-wire anemometers and aerosol concentration monitors were used to deduce these effects as the two-phase mist flow gradually developed in the stream-wise direction. We found significant axial mist diffusion at Reynolds numbers (Re) 2400, a sharp mist waveform was maintained by a turbulent flow with active radial mixing. New data were obtained within the range of 1000

Studies that characterize the performance of low-cost particulate matter (PM) sensors are needed to help practitioners understand the accuracy and precision of the mass and number concentrations reported by different models. We evaluated Plantower PMS5003, Sensirion SPS30, and Amphenol SM-UART-04L PM sensors in the laboratory by exposing them to: (1) four different polydisperse aerosols (ammonium sulfate, Arizona road dust, NIST Urban PM, and wood smoke) at concentrations ranging from 10 to 1000 μg m−3, (2) hygroscopic and hydrophobic aerosols (ammonium sulfate and oil) in an environment with varying relative humidity (15%–90%), (3) polystyrene latex spheres (PSL) ranging from 0.1 to 2.0 μm in diameter, and (4) extremely high concentrations of Arizona road dust (18-h mean total PM = 33,000 μg m−3; 18-h mean PM2.5 = 7300 μg m−3). Linear models relating PMS5003- and SPS30-reported PM2.5 concentrations to TEOM-reported ammonium sulfate concentrations up to 1025 μg m−3, nebulized Arizona road dust concentrations up to 540 μg m−3, and NIST Urban PM concentrations up to 330 μg m−3 had R2 ≥ 0.97; however, an F-test identified a significant lack of fit between the model and the data for each sensor/aerosol combination. Ratios of filter-derived to PMS5003-reported PM2.5 concentrations were 1.4, 1.7, 1.0, 0.4, and 4.3 for ammonium sulfate, nebulized Arizona road dust, NIST Urban PM, wood smoke, and oil mist, respectively. For SPS30 sensors, these ratios were 1.6, 2.1, 2.1, 0.6, and 2.2, respectively. Collocated PMS5003 sensors were less precise than collocated SPS30 sensors when measuring ammonium sulfate, nebulized Arizona road dust, NIST Urban PM, oil mist, or PSL. Our results indicated that particle count data reported by the PMS5003 were not reliable. The number size distribution reported by the PMS5003 (a) did not agree with APS data and (b) remained roughly constant whether the sensors were exposed to 0.1 μm PSL, 0.27 μm PSL, 0.72 μm PSL, 2.0 μm PSL, or any of the other laboratory-generated aerosols. The size distribution reported by the SPS30 did not always agree with APS data, but did shift towards larger particle sizes when the sensors were exposed to 0.72 PSL, 2.0 μm PSL, oil mist, or Arizona road dust from a fluidized bed generator. The proportions of PM mass assigned as PM1, PM2.5, and PM10 by all three sensor models shifted as the PSL size increased. After the sensors were exposed to high concentrations of Arizona road dust for 18 h, PM2.5 concentrations reported by SPS30 sensors remained consistent, whereas 3/8 PMS5003 sensors and 2/7 SM-UART-04L sensors began reporting erroneously high values.

Machining plants are often highly polluted indoor environments with dense oil mist generated from metalworking fluids. Workers exposed to oil mist may suffer serious health problems. General ventilation is often used to dilute the oil mist level below the threshold of health risk. However, it is not easy to organize the flow for ventilating a large machining plant with hundreds of machines in order to effectively remove the oil mist. In order to develop an effective ventilation system, this study validated a computational fluid dynamics (CFD) program with the RNG k-e model at a high Grashof number by using the measured air temperature and contaminant concentration in several locations in a high-ceiling lab with heat and pollutant sources. Next, the validated CFD program was used to develop an improved displacement ventilation system in which air is supplied from the lower parts of the support columns in the plant. With thermal plumes generated by machines and workers, the system formed unidirectional airflow that carried pollutants away from the work area of the factory. The system reduced the oil-mist concentration by more than 70% compared with existing ventilation system. In addition, suspended radiant heaters are recommended for supplemental heating in winter.

The aim was to assess pneumoproteins and a certain biomarker of systemic inflammation in drill floor workers exposed to airborne contaminants generated during drilling offshore, taking into consideration serum biomarkers of smoking, such as nicotine (S-Nico) and cotinine. Blood samples of club cell protein 16 (CC-16), surfactant protein D (SP-D) and C-reactive protein (CRP) were collected before and after a 14-day work period from 65 drill floor workers and 65 referents. Air samples of oil mist, drilling mud components and elemental carbon were collected in person. The drill floor workers were exposed to a median air concentration of 0.18 mg/m3 of oil mist and 0.14 mg/m3 of airborne mud particles. There were no differences in the concentrations of CC-16 and SP-D across the 14-day work period and no difference between drill floor workers and referents at baseline after adjusting for differences in sampling time and smoking. CRP decreased across the work period. There was a strong association between the CC-16 concentrations and the time of sampling. Current smokers with S-Nico &gt, detection limit (DL) had a statistically significantly lower CC-16 concentration, while smokers with S-Nico &lt, DL had CC-16 concentrations similar to that of the non-smokers. Fourteen days of work offshore had no effect on serum pneumoprotein and CRP concentrations. However, the time of blood sampling was observed to have a strong effect on the measured concentrations of CC-16. The effect of current smoking on the CC-16 concentrations appears to be dependent on the S-Nico concentrations.

Road tunnel construction involves the use of explosives and diesel-powered machines in a very limited indoor space. Tunnel construction workers are thus exposed to a variety of toxic substances, including dust, asbestos, silica, concrete, diesel fumes, and oil mist. In this study, the low noise miniaturized Sioutas Cascade Impactor (SKC) has been used to collect PM samples as a function of particle size (i.e., aerodynamic diameter). Airborne particulates were sampled into a road tunnel (final length 2391 m) under construction near the village of Pale, Municipality of Foligno, Umbrian Apennines (State Highway 77 “Val di Chienti”). Three sampling sessions were performed: (i) in the West yard, during dislodging of rocks; (ii) in the East yard during drilling of rocks, and (iii) during scaling and grouting with quick-drying shotcrete. The aim of this study was to characterize size-fractionated PM samples for their cytotoxic/genotoxic potentials. Toxicological evaluation was carried out in vitro on A549 lung carcinoma cells: cytotoxicity was assessed by Trypan blue dye exclusion assay, whereas genotoxicity was assessed by comet assay (primary DNA damage) and cytokinesis-block micronucleus (CBMN) Cytome assay (cytogenetic effects). Primary DNA damage (i.e., strand breakage) was mainly caused by coarse fractions A (O > 2.5 μm) sampled in the West yard (sample i) and in the East yard (sample iii). Cytogenetic effects were mainly caused by the fine fractions AF (aerodynamic O

Quantitative assessment of human exposure to semi-volatile organic compounds (SVOC), such as tricresyl phosphates (TCP) that may originate from engine oil contamination of the cabin air, during air travel is challenging due to the technical complexity of the air supply in commercial jet aircraft. Normal flight operations involve reduced air exchange before and during takeoff, which results in increased concentrations of potential cabin air pollutants. During cruise, normal ventilation rates (>20 h− 1) are reestablished and thus lower pollutant concentrations are also reestablished. This relationship between changes in ventilation rate and associated changes in pollutant concentrations during the departure phase is first described in the present study, although this effect was found by previous studies that investigated distinct flight phases. The perception of so-called "smell events" in cabin air does not necessarily indicate the presence of harmful contaminants and TCP-containing oil mist must be clearly distinguished thereof. Thus, aldehydes, VOCs, and organophosphates such as TCP were investigated. In this paper, the occurrence of TCP contamination in a bleed air free Boeing 787 (B787) aircraft is reported for the first time. The results presented here show that there are TCP sources other than bleed air from leaky engines. Furthermore, exceptional release behavior of TCP suggests that a more detailed classification for engine oil-triggered cabin air contamination (CAC) events is necessary. This study evaluated measurement data from 177 flights that were either commissioned by the EASA or conducted as part of studies with the support of Lufthansa, Condor, and British Airways.

Bearing failure is one of the major concern in Indian Steel Industries as the failure leads to breakdown of the machine and thereby causes huge production loss. Bearing performance depends on design, selection of bearing type, lubricant and the type of maintenance practice chosen for it. In Steel industries there is not much scope to play for enhancing the bearing performance except good maintenance practice and manoeuvre with the lubricant and lubrication system. It is desired for any lubrication or lubrication system to optimise lubricant consumption without compromising the performance /life of the bearing. There are many systems which can provide lubricant with desired viscosity to the bearings. Grease is sticky, so it gets contaminated quickly. Consumption of grease is a bit higher and it does not help to increase the mill speed. The oil mist lubrication is better than grease lubrication system. But it has the problem of atomise oil droplet mix with air which creates foggy and unhealthy atmosphere in the shop/plant. The Air-Oil lubrication system sends metered quantity of lube oil in the form of oil streak through a distributor, carried by dry compressed air into bearing to lubricate it. The carrier air prevents entry of foreign particle in the lubricant and avoids lube oil contamination. It also helps in reaching the lubricant into the bearing clearance to maintain an oil film and it avoids the direct contact with rolling elements and races. Here in this work an attempt is made to enhance the performance of taper roller bearing of Cold Rolling Mill by implementing Air- Oil Lubrication system.

The aim was to study exposure to airborne contaminants in oil drillers during ordinary work. Personal samples were collected among 65 drill floor workers on four stationary and six moveable rigs in the Norwegian offshore sector. Air concentrations of drilling mud were determined based on measurements of the non-volatile mud components Ca and Fe. The median air concentration of mud was 140 μg m(-3). Median air concentrations of oil mist (180 μg m(-3)), oil vapour (14 mg m(-3)) and organic carbon (46 μg m(-3)) were also measured. All contaminants were detected in all work areas (drill floor, shaker area, mud pits, pump room, other areas). The highest air concentrations were measured in the shaker area, but the differences in air concentrations between working areas were moderate. Oil mist and oil vapour concentrations were statistically higher on moveable rigs than on stationary rigs, but after adjusting for differences in mud temperature the differences between rig types were no longer of statistical significance. Statistically significant positive associations were found between mud temperature and the concentrations of oil mist (Spearman's R = 0.46) and oil vapour (0.39), and between viscosity of base oil and oil mist concentrations. Use of pressure washers was associated with higher air concentrations of mud. A series of 18 parallel stationary samples showed a high and statistically significant association between concentrations of organic carbon and oil mist (r = 0.98). This study shows that workers are exposed to airborne non-volatilized mud components. Air concentrations of volatile mud components like oil mist and oil vapour were low, but were present in all the studied working areas.

Aluminium workers are exposed to a complex mixture of airborne chemicals. Workers in different stages of aluminium manufacturing are exposed to different mixtures of chemicals. At twelve US aluminium facilities, we used information from an industrial hygiene database containing 30 years of sampling results for 227 separate chemical agents to build job exposure matrices (JEMs). We selected chemicals that represented major exposures in the workplace (e.g., oil mist and fluorides) and those that have been associated with heart disease [e.g., polycyclic aromatic hydrocarbons (PAHs) and welding-related metals]. We used cluster analysis to empirically group the chemical agents and establish exposure profiles by job. For PAHs and welding-related metal exposures, we also built quantitative JEMs. There were 21 PAH chemical agents, including individual PAHs (e.g. benzo[a]pyrene) and groups of PAHs (e.g. coal tar pitch volatiles). For metals, there were 54 different chemical agents associated with welding tasks. The categorical JEMs have three categories of exposure: unmeasured, very low exposure, and moderate or higher exposure. The stage of the manufacturing process made a large impact on the distribution of exposures. While 62% of jobs in smelters involved PAH exposures, only 2% of jobs in fabrication facilities did. Conversely, oil mist exposure is more common in fabrication facilities, compared with smelters (24% and 7% of jobs exposed, respectively). We observed that the exposure profiles in smelters was very different to those observed in fabrication facilities or refineries. These chemical exposure JEMs will help clarify the role chemicals play in heart disease.

An integrated approach was developed to assess exposure and health-risk from polycyclic aromatic hydrocarbons (PAHs) contained in oil mists in a fastener manufacturing industry. One previously developed model and one new model were adopted for predicting oil mist exposure concentrations emitted from metal work fluid (MWF) and PAHs contained in MWF by using the fastener production rate (Pr) and cumulative fastener production rate (CPr) as predictors, respectively. By applying the annual Pr and CPr records to the above two models, long-term workplace PAH exposure concentrations were predicted. In addition, true exposure data was also collected from the field. The predicted and measured concentrations respectively served as the prior and likelihood distributions in the Bayesian decision analysis (BDA), and the resultant posterior distributions were used to determine the long-term exposure and health-risks posed on workers. Results show that long term exposures to PAHs would result in a 3.1%, 96.7%, and 73.4% chance of exceeding the PEL-TWA (0.2 mg/m3), action level (0.1 mg/m3), and acceptable health risk (10−3), respectively. In conclusion, preventive measures should be taken immediately to reduce workers’ PAH exposures.

Figure 1 is showing the gravimetric measurement system Topas GMS 141. The system is used to measure the condensate and oil concentration (oil carryover) in the full blow by stream of combustion engines. The quantity of the fluid blow by fraction is measured by the determination of the mass of a filter paper. The oil emission is determined in a steady state condition of the engine.

Dust collecting performance of axial-vane type cyclone for oil mist was analyzed in this study. For predicting cut diameter size of cyclone, the number and angle of vane (tanβ2' ) was calculated by CFD. As the result, tanβ2' was decreased as the number of vane was increased and the angle of inclination (β2' ) decreased, and it cause strong swirl flow. Therefore, it could be confirmed that as the number of vane was increased and the angle of inclination was decreased, cut diameter size was decreased. Also, by verifying the results of CFD through experiment, the cut diameter size could be 2 μm at 4 m 3 /min of flow rate.

Collecting multiple and long-term samples is necessary to accurately describe the exposure profile of a similar exposure group (SEG), but only a few industries can afford to do this because of the costs and manpower needed. In the present study, measured oil mist concentrations (Cm, n = 11) were randomly collected on eleven days during one year (serving as the likelihood distribution in Bayesian decision analysis (BDA)), and daily fastener production rates (Pr, n = 250) were used as a surrogate for predicting the yearlong oil mist exposure concentrations (Cp) (serving as the prior distribution in BDA). The resulting BDA posterior distributions were used to assess the long-term oil mist exposures to threading workers in a fastener manufacturing industry. The feasibility of the proposed methodology was finally examined with reference to the effects of the sample size of the Cm. The results show that threading workers experienced more severe thoracic and respirable oil mist exposure than exposure to the inhalable fraction. Using Pr as a surrogate was adequate to explain ~92% of the variations in Cm. By combining Cp and Cm, our results suggest that the BDA technique adopted in this work was effective in predicting workers' long-term exposure. By judging the consistency of the resulting posterior exposure ratings, this study suggests that the proposed methodology could be feasible, even when the sample size of Cm is set as low as 3.

The effects of draft on the flow and spillage characteristics of wall-mounted and jet-isolated range hoods were investigated. A specially designed draft generator that could supply low-swirl air current was used to provide "cross draft" from three directions, lateral (θ = 0(o)), oblique (θ = 45(o)), and front (θ = 90(o)), with respect to the center point of the range hoods. Flow characteristics of oil mist were inspected through visualization of smoke flows with light scattering (laser light sheet-assisted visualization of smoke flow). The leakage mechanisms, which were closely related to the flow features, were studied by examining both movies and still pictures showing smoke-flow evolution. The sulfur hexafluoride tracer gas concentration detection method was employed to measure the capture indices. The results showed that the lateral draft pushed the pollutants generated under the hood in the opposite direction and induced serious spillage. The oblique draft pushed the pollutants toward both the rear wall and opposite side and induced more serious spillage than did the lateral draft. The frontal draft forced the pollutants to bifurcate into streams moving toward the left and the right, and induced the most serious pollutant spillage among the three tested drafts. Pollutant spillage became critically significant as the cross draft velocity was increased to greater than 0.2 m/sec. Spillage of pollutants increased as the velocity of the cross draft was increased. Increasing the suction flow rate of the range hood may increase resistance to the draft, but the benefits were limited at draft velocities greater than 0.2 m/sec. Both range hoods had a similarly low capture index under the influence of the lateral draft. For the oblique and frontal drafts, the jet-isolated range hood demonstrated a higher capture index than did the wall-mounted range hood.

The high-concentration pickling and the extreme emission and energy consumption of the precision saponification process before the cold finishing of the precision forgings of the constant speed drive shaft of the car. Oil mist emissions from the cold finishing process and relatively harsh working conditions. The purpose of this paper is to develop a new saponification process that saves energy and reduces emissions while ensuring product quality during production. Through a large number of tests, it shows that the saponification of precision forgings for the drive shaft can be completed by three steps including simple saponification liquid spraying, liquid extraction and hot air drying. Thus in this way, the saponification quality is the best, At the same time, it has greatly reduced emissions, while the instability of the saponification quality mainly relates to the control of saponification process.

Respiratory problems are observed in machinists using soluble metalworking fluid (MWF). Evidences suggest that these problems could be related to the aerosolized microorganisms and their byproducts from MWF. To establish MWF aerosol exposure thresholds and to better understand their effect on human health, these aerosols must be fully characterized. This article evaluates airborne microorganisms and aerosols from soluble MWF in the working environment. Air quality parameters (endotoxin levels, culturable airborne microorganisms, fluid mist, inhalable dust and air exchange rates) were evaluated at 44 sites, in 25 shops in Quebec, Canada. Microorganism concentrations were also measured in MWF. Culturable airborne bacteria concentrations were low, ranging from 1.2 x 10(1) to 1.5 x 10(3) CFU (colony forming units) m(-3), even for metalworking fluid highly contaminated by bacteria (up to 2.4 x 10(9) CFU mL(-1)). Inhalable dust varied between0.1 to 2.6 mg m(-3), while air exchange rates were mostly below the standard (4 h(-1)) for this type of workplace, between 0.6 to 14.2 h(-1). Only nine of 44 sites respected the suggested minimum value for air exchange rates. Fluid mist ranged from 0.02 to 0.89 mg m(-3), which is below the threshold limit value (TLV) (ACGIH) of 5 mg m(-3). Airborne endotoxin concentrations ranged from undetectable to 183 EU m(-3) (endotoxin units), showing no correlation with airborne microorganisms or inhalable dust. Most workstations respected the suggested minimum values for fluid mist and showed low concentrations of airborne endotoxin, culturable microorganisms and inhalable dust despite fluid contamination, even when air exchange rates were below the recommendations. Airborne Pseudomonas pseudoalcaligenes was recovered from many sites at significant concentrations. Health-associated risks following exposure to this microorganism should be further investigated.

This study was set out to characterize size distributions of oil mists in three workplace atmospheres of the forming, threading, and heat treatment in a fastener manufacturing industry and to assess their exposures to workers. Particle size segregating samplings were conducted on the workplace atmospheres of the three selected industrial processes by using the modified Marple 8-stage cascade impactor (m-Marple). We found that mass median aerodynamic diameter (MMAD) of the fine mode and coarse mode fell to the range 0.309-0.501 microm and 8.16-13.0 microm, respectively. The fractions of inhaled particles exposed to different regions of the respiratory tracts found that the alveolar region was consistently higher than both head and tracheobronchial regions in all three studied exposure groups. Personal inhalable oil mist samplings were conducted on workers in the three selected processes revealed their exposure levels as: threading workers (2.11 mg/m3)>forming workers (1.58 mg/m3)>heat treatment workers (0.0801 mg/m3). The estimated respirable exposure concentrations for both forming and threading workers (1.34 mg/m3 and 1.40 mg/m3, respectively) were higher than the level known for "increased risk of pulmonary injury" (0.20 mg/m3) suggesting that appropriate control measures should be taken to reduce their exposures to the oil mists of the respirable fraction immediately.

The uncertainty of a new primary standard for hydrocarbon flow measurements has been evaluated analytically and experimentally in detail in accordance with the “ISO Guide to the expression of uncertainty in measurement”. The expanded uncertainty has been estimated to be 0.03% for volumetric flow rate and 0.02% for mass flow rate (coverage factor : k=2). This evaluation shows that the uncertainty of duration time when liquid is accumulated into the weighing tank is negligible by using the new diverter, and that the dominant sources of combined uncertainty of flow rate are the mass of oil accumulated in the weighing tank and the density of oil flowing through the flowmeter under test. In particular, the uncertainty in the low flow rate at the kerosene test rig using the 10t weighing system is quite larger than those at the other test rigs due to the loss of oil caused by oil mist and vapor discharged from the diverter and the weighing tank. Furthermore, the uncertainties of temperature measurements at the test meter and the density meter have large effect of the combined uncertainty of volumetric flow rate.