Main control factors affecting mechanical oil recovery efficiency in complex blocks identified using the improved k-means algorithm.

The system efficiency of pumping units in the middle and late stages of oil recovery is characterized by several factors, complex data and poor regulation. Further, the main control factors that affect system efficiency in different blocks vary greatly; therefore, it is necessary to obtain the block characteristics to effectively improve system efficiency. The k-means algorithm is simple and efficient, but it assumes that all factors have the same amount of influence on the output value. This cannot reflect the obvious difference in the influence of several factors in the block on the efficiency. Moreover, the algorithm is sensitive to the selection of the initial cluster centre point, so each calculation result that reflects the efficiency characteristics of the block system cannot be unified. To solve the aforementioned problems affecting the k-means algorithm, the correlation coefficient of all the factors was first calculated, followed by extracting the system efficiency of the positive and negative indicators of standardization. Next, the moisture value was calculated to obtain the weight of each factor used as a coefficient to calculate the Euclidean distance. Finally, the initial centre point selection of the k-means algorithm problem was solved by combining the dbscan and weighted k-means algorithm. Taking an oil production block in the Daqing Oilfield as the research object, the k-means and improved algorithm are used to analyse the main control factors influencing mechanical production efficiency. The clustering results of the two algorithms have the characteristics of overlapping blocks, but the improved algorithm's clustering findings are as follows: this block features motor utilization, pump efficiency and daily fluid production, which are positively correlated with system efficiency. Further, low-efficiency wells are characterized by the fact that the pump diameter, power consumption, water content, daily fluid production, oil pressure and casing pressure are significantly lower than the block average; high-efficiency wells are characterized by pump depths lower than the block average. For this block, it is possible to reduce the depth of the lower pump and increase the water-injection effect to increase the output under conditions of meeting the submergence degree, which can effectively improve the system efficiency.

Workforce perceptions of human factors as indicators of plant reliability and process safety.

Human factors, as perceived by the maintenance workforce, were used as the measure for comparing work areas within a petroleum company. These factors were then compared to an objective measure of reliability (Mean Time Between Failures) in order to determine which factors would be most predictive of plant reliability and process safety. Maintenance personnel were surveyed using scales based on Problem-solving, Vigilance, Design and maintenance, Job-related feedback and Information about change. Analysis of Variance was used to assess the strength of these variables in relation to Reliability Level. Significant differences were observed between different reliability levels based on workforce perceptions of problem-solving requirements and the design and maintainability of plant. Conclusions were that perceptions of human factors in the workplace can be predictive of group-level performance, and that if issues relating to design and maintainability are not addressed at the design stage, greater problem-solving abilities will be required from maintenance personnel. Practitioner summary: Workforce perceptions of plant performance could provide a statistically valid measure of current and future reliability. A survey of perceptions of human factors was conducted with maintenance personnel in a petroleum company. Results indicated significant relationships between reliability and requirements for Problem-solving, as well as Design and Maintenance of equipment. Abbreviations: HFIT: human factors investigation tool, FPSO: floating production, storage and offtake, MTBF: mean time between failures, CPS: cognitive problem- solving, WDS: work design questionnaire, SPSS: statistical package for the social sciences, PAF: principal axis factoring, ANOVA: analysis of variance, ANCOVA: analysis of co-variance, M: mean, SD: standard deviation.

Hearing protective devices and its role in Noise induced hearing loss: An interventional study.

This Quasi experimental study was conducted with the objective to determine the effectiveness of preventive measures including awareness programme and use of hearing protective devices (HPDs) for the prevention and control of Noise Induced Hearing Loss among Oil and Gas field workers from January 2015 to March 2016. A total of 120 workers were selected by convenient sampling, and subjected to pure tone audiometry (PTA) to obtain hearing thresholds followed by intervention with HPDs and retesting a year later. The Mean pure tone thresholds on first visit was 21.19±11.60 dB in right and 24.66±13.26 dB in left ear, while means at second visit (after one year) were 20.65±10.44 dB and 21.45±11.74 dB for the right and left ears respectively with statistically significant difference (p=0.001) for the left ear on t-test. However the difference of frequency and percentage of the participants with normal and reduced hearing at both visits was significant (chi square P=0.001). Hearing protective devices (HPDs) are an effective means to prevent NIHL in workers of oil and gas fields.

Assessment of the physical impact of a short-term dredging operation on a semi-enclosed environment: South Euboean Gulf, Greece.

The potential influence of short-period (May-June 2012) dredging activities (for the installation of a submarine gas pipeline) on physical properties of the marine environment of two shallow-water sites in the Aliveri and Varnavas areas of South Euboean Gulf (Greece) has been evaluated. During the dredging operation in Varnavas, the induced dredge plume traveled up to ~ 750 m from the shoreline, featured by light attenuation coefficient (cp) maxima of 4.01-4.61 m-1 and suspended particulate matter (SPM) concentrations up to 6.01 mg L-1. After dredging the previous parameters reduced to the ambient seawater condition, ~ 0.45 m-1 and < 2.8 mg L-1 on average, respectively. Likewise in Aliveri, the dredging-associated sediment plume drifted offshore up to ~ 400 m from the shoreline, characterized by cp maxima of 2.11-4.86 m-1 and SPM concentrations up to 13.07 mg L-1. After the completion of the excavation and trenching activities, the cp and SPM values were restored to the pre-disturbance condition, ~ 0.6 m-1 and < 2.2 mg L-1 on average, respectively. The migration of the dredge plume in both dredging sites was accomplished through the formation of intermediate and benthic nepheloid layers, whose development and evolution were governed by seawater stratification and flow regime. The dredging-derived SPM levels appeared to increase within a distance of no more than 300 m from the shoreline (near-field zone). Based on data from the literature, this SPM enhancement together with the deposition of a post-dredging residual mud veneer in the near-field zone could deteriorate local marine biota, but in a reversible way.

Implementation of an Interdisciplinary Approach to Promote Workers Global Health Status in the Oil Industry, Brazil (2006-2015).

This study intends to analyse the behaviour of epidemiological variables of workers in anoilindustry of Bahia, Brazil, before and after implementation of interdisciplinary practices in occupational health assessments between 2006 and 2015. This is a retrospective longitudinal study carried out in two time periods. Data were collected from the workers electronic medical record and time trends were analysed before (2006-2010) and after (2011-2015) the implementation of the interdisciplinary practices focusing on health promotion. The data were complementarily compared to a control group from the same industry.A statistically significant reduction for data on the number of smokers, periodontal disease and of days away from work was obtained. A significant increase in the number of physically active subjects wasalso observed. Whilenot statistically significant, a reduction in the number of workers with obesity and overweight, with caries and altered glycemia, was identified. Coronary risk and high blood pressure indicators have shown aggravation. It can be concluded that an interdisciplinary health approach during the annual occupational assessments, with action directed to the population needs, can be associated with the improvement of the health indicators assessed, contributing to increased worker productivity in the oil industry.

Occupational fatigue and mental health complaints among 8-hour shift workers of petrochemical industries in Iran.

BACKGROUND: Shift working is unavoidable in many industries with continual material processing such as petrochemical plants. So, the adverse effects of shift working on workers should be seriously considered. OBJECTIVE: This cross-sectional study evaluated occupational fatigue and mental health complaints and their relationship in rotating 8-hour shift workers. METHOD: In this study, 287 shift workers participated. The Multidimensional Fatigue Inventory (MFI-20) and General Health Questionnaire (GHQ-28) were used to evaluate the level of fatigue and mental health, respectively. RESULT: A relatively high prevalence of mental health complaints (particularly social dysfunction) and fatigue (especially general fatigue) were found among the study population. In general, 43.4% of participants reported a mental health problem. A moderate correlation was found between fatigue and mental health (r = 0.58). The stepwise regression model revealed that fatigue was significantly related only to "anxiety and insomnia" and "severe depression". CONCLUSION: This study revealed that the 8 h shift workers in studied areas are exposed to a considerable risk of mental health and fatigue. So, improving the ergonomics and health aspects of the workplace is recommended to reduce related risk factors.

Aerially guided leak detection and repair: A pilot field study for evaluating the potential of methane emission detection and cost-effectiveness.

Novel aerial methane (CH4) detection technologies were used in this study to identify anomalously high-emitting oil and gas (O&G) facilities and to guide ground-based "leak detection and repair" (LDAR) teams. This approach has the potential to enable a rapid and effective inspection of O&G facilities under voluntary or regulatory LDAR programs to identify and mitigate anomalously large CH4 emissions from a disproportionately small number of facilities. This is the first study of which the authors are aware to deploy, evaluate, and compare the CH4 detection volumes and cost-effectiveness of aerially guided and purely ground-based LDAR techniques. Two aerial methods, the Kairos Aerospace infrared CH4 column imaging and the Scientific Aviation in situ aircraft CH4 mole fraction measurements, were tested during a 2-week period in the Fayetteville Shale region contemporaneously with conventional ground-based LDAR. We show that aerially guided LDAR can be at least as cost-effective as ground-based LDAR, but several variable parameters were identified that strongly affect cost-effectiveness and which require field research and improvements beyond this pilot study. These parameters include (i) CH4 minimum dectectable limit of aerial technologies, (ii) emission rate size distributions of sources, (iii) remote distinction of fixable versus nonfixable CH4 sources ("leaks" vs. CH4 emissions occurring by design), and (iv) the fraction of fixable sources to total CH4 emissions. Suggestions for future study design are provided. Implications: Mitigation of methane leaks from existing oil and gas operations currently relies on on-site inspections of all applicable facilities at a prescribed frequency. This approach is labor- and cost-intensive, especially because a majority of oil and gas-related methane emissions originate from a disproportionately small number of facilities and components. We show for the first time in real-world conditions how aerial methane measurements can identify anomalously high-emitting facilities to enable a rapid, focused, and directed ground inspection of these facilities. The aerially guided approach can be more cost-effective than current practices, especially when implementing the aircraft deployment improvements discussed here.

Pseudo-source parameters for flares: Derivation, implementation, and comparison.

The United States Environmental Protection Agency (US EPA) flare pseudo-source parameters are over 30 years old and few dispersion modellers understand their basis and underlying assumptions. The calculation of plume rise from the user inputs of pseudo-stack diameter, temperature and velocity have the most influence on air dispersion model predictions of ground-level concentrations. Regulatory jurisdictions across Canada, the United States and around the world have adopted their own approach to pseudo-source parameters for flares; all relate buoyancy flux to the heat release rate, none consider momentum flux and flare tip downwash as adopted by the Alberta Energy Regulator (AER). This paper derives the plume buoyancy flux for flares burning a gas in terms of combustion variables readily known or calculated without simplifying assumptions. Dispersion model prediction sensitivity to flared gas composition, temperature and velocity, and ambient conditions are now correctly handled by the AER approach. The AER flare pseudo-source parameters are based on both the buoyancy and momentum flux, thus conserving energy and momentum. The AER approach to calculate the effective source height for flares during varying wind speeds is compared to the US EPA approach. Instead of a constant source for all meteorological conditions, multiple co-located sources with varying effective stack height and diameter are used. AERMOD is run with the no stack tip downwash option as flare stack tip downwash is accounted for in the effective stack height rather than the AERMOD model calculating the downwash incorrectly using the pseudo-source parameters. The modelling approaches are compared for an example flare. Maximum ground level predictions change, generally increasing near the source and decreasing further away, with the AER flare pseudo-source parameters. It's time to update how we model flares. Implications: What are the implications of continuing to model flare source parameters using the overly simplified US EPA approach? First, the regulators perpetuate the myths that the flare source height, temperature, diameter and velocity are constant for all wind speeds and ambient temperatures. Second, that it is acceptable to make simplifying assumptions that violate the conservation of momentum and energy principles for the sake of convenience. Finally, regulatory decisions based on simplified source modelling result in predictions that are not conservative (or realistic). The AER regulatory approach for flare source parameters overcomes all of these shortcomings. AERflare is a publicly available spreadsheet that provides the "correct" inputs to AERMOD.

Monitoring wastewater discharge from the oil and gas industry using passive sampling and Danio rerio bioassay as complimentary tools.

Produced water (PW) represents the largest volume waste stream in oil and gas production operations from most offshore platforms. PW is difficult to monitor as releases are rapidly diluted and concentrations can reach trace levels. The use of passive samplers can over come this. Here polyethylene (PE) was calibrated for a diverse range of PW pollutants. Zebrafish were exposed to dilutions of PW and passive sampler extracts in order to investigate the relationship between freely dissolved chemical concentrations and acute toxic effects. The raw PW had an LC50 of 13% (percentage of PW in the standardized zebrafish medium). Observed non-viable deformations to embryos (at 5 hpf) included heart and yolk edema, head, spine and tail deformations. The dose-response relationship of lethal effects showed that if 0.0041 g of PE is exposed to this PW, then extracted, 50% of exposed D. rerio will suffer lethal effects. The sum of tested freely dissolved concentrations that led to 50% lethal effects (mortality and non-viable deformations) was 2.32 × 10-4 mg/L for PW and 7.92 × 10-2 mg/L for PE. This implies that exposure to raw PW was more toxic than exposure to PE extracts. This toxicity was attributed both to the presence of contaminants as well as PW salinity. Passive samplers are able to detect very low freely dissolved pollutant concentrations which is important for assessing the spatial dilution of PW releases. Bioassays provide complimentary information as they account for all toxic compounds including those that are not taken up by passive samplers.

Remote sensing assessment of oil spills near a damaged platform in the Gulf of Mexico.

An oil platform in the Mississippi Canyon 20 (MC-20) site was damaged by Hurricane Ivan in September 2004. In this study, we use medium- to high-resolution (10-30 m) optical remote sensing imagery to systematically assess oil spills near this site for the period between 2004 and 2016. Image analysis detects no surface oil in 2004, but ~40% of the cloud-free images in 2005 show oil slicks, and this number increases to ~70% in 2006-2011, and >80% since 2012. For all cloud-free images from 2005 through 2016 (including those without oil slicks), delineated oil slicks show an average oil coverage of 14.9 km2/image, with an estimated oil discharge rate of 48 to ~1700 barrels/day, and a cumulative oil-contaminated area of 1900 km2 around the MC-20 site. Additional analysis suggests that the detected oil slick distribution can be largely explained by surface currents, winds, and density fronts.

Prevalence of musculoskeletal pains and effect of work-related factors among employees on offshore oil and gas installations in Iran.

BACKGROUND: Work-related musculoskeletal pain is usually caused by poor physical conditions, repetitive motion, and adverse environmental and psychological situations. OBJECTIVE: This study aims to assess the prevalence of musculoskeletal pain and their work-related factors among employees on offshore oil and gas installations in Iran. METHODS: Standardized Nordic Questionnaire was used to collect data. The relationship of musculoskeletal pain with job type, rest breaks, exercise, shift program, and work period was studied among employees on offshore installations. T-test and ANOVA were used for data analysis. RESULTS: Employees on offshore installations were exposed to high levels of risk of musculoskeletal pain in their knees and back. Consequently, they reported the highest level of complaints of pain in the neck and lower back areas. Workers in drilling and tour-scheduling jobs reported the highest level of musculoskeletal pain. In the course of seven days and 12 months, the highest level of significant relationship was observed between the limbs and the work periods (tour scheduling or days-off) of the staff. CONCLUSION: The findings showed that the prevalence of musculoskeletal disorders among employees of offshore facilities was high due to inappropriate working conditions such as repetitive work, lifting heavy loads and limited rest periods. Therefore, strategies must be considered to reduce the effects of disorders.

Frequency Analysis of Failure Scenarios from Shale Gas Development.

This study identified and prioritized potential failure scenarios for natural gas drilling operations through an elicitation of people who work in the industry. A list of twelve failure scenarios of concern was developed focusing on specific events that may occur during the shale gas extraction process involving an operational failure or a violation of regulations. Participants prioritized the twelve scenarios based on their potential impact on the health and welfare of the general public, potential impact on worker safety, how well safety guidelines protect against their occurrence, and how frequently they occur. Illegal dumping of flowback water, while rated as the least frequently occurring scenario, was considered the scenario least protected by safety controls and the one of most concern to the general public. In terms of worker safety, the highest concern came from improper or inadequate use of personal protective equipment (PPE). While safety guidelines appear to be highly protective regarding PPE usage, inadequate PPE is the most directly witnessed failure scenario. Spills of flowback water due to equipment failure are of concern both with regards to the welfare of the general public and worker safety as they occur more frequently than any other scenario examined in this study.

Challenging the immediate causes: A work accident investigation in an oil refinery using organizational analysis.

BACKGROUND: In many companies, investigations of accidents still blame the victims without exploring deeper causes. Those investigations are reactive and have no learning potential. OBJECTIVE: This paper aims to debate the historical organizational aspects of a company whose policy was incubating an accident. METHODS: The empirical data are analyzed as part of a qualitative study of an accident that occurred in an oil refinery in Brazil in 2014. To investigate and analyse this case we used one-to-one and group interviews, participant observation, Collective Analyses of Work and a documentary review. The analysis was conducted on the basis of concepts of the Organizational Analysis of the event and the Model for Analysis and Prevention of Work Accidents. RESULTS: The accident had its origin in the interaction of social and organizational factors, among them being: excessively standardized culture, management tools and outcome indicators that give a false sense of safety, the decision to speed up the project, the change of operator to facilitate this outcome and performance management that encourages getting around the usual barriers. CONCLUSIONS: The superficial accident analysis conducted by the company that ignored human and organizational factors reinforces the traditional safety culture and favors the occurrence of new accidents.

Genotoxic Effects of Exposure to Gasoline Fumes on Petrol Pump Workers.

BACKGROUND: Petrol pump workers are occupationally exposed to gasoline and its fumes consisting of several mutagenic chemicals. OBJECTIVE: To evaluate the genotoxic effects of exposure to gasoline fumes on petrol pump workers. METHODS: The study groups included 70 petrol pump workers (exposed group) and 70 healthy age-matched individuals with no known exposure (comparison group). Buccal micronucleus cytome assay (BMCyt) was performed to check the genotoxicity caused due to inhalation of gasoline fumes. RESULTS: The frequencies of micronucleated cells, nuclear bud, condensed chromatin cells, karyorrhectic cells, pyknotic cells, and karyolytic cells were significantly higher in the exposed workers compared to the comparison group. CONCLUSION: Exposure to gasoline fumes is associated with increased frequency of cell abnormalities. This may lead to various health consequences including cancer in those occupationally exposed to gasoline fumes.

Work-leave rotation pattern and incidence of offshore workplace injury.

Background: Studies on work-leave rotation pattern and work place injuries among offshore oil and gas workers have been few and limited to a 2- or 3-week rotation schedule. Aims: To examine incidence of workplace injury in relation to the duration of time into work rotation for extended work schedules up to 24 weeks. Methods: Six-year injury data on four offshore installations were extracted. Data were analysed for incidence of injury over time and relative risk using linear trend lines and regression. Results: In total, 311 injuries for 1302 workers were analysed, 39% with rotation schedule of 4 weeks work and 4 weeks rest, 27% 8 weeks work and 4 weeks rest, 23% 16 weeks work and 4 weeks rest and 10% 24 weeks work and 4 weeks rest. Incidence of injury decreased as duration of time into the work rotation increased, corrected for exposure, and this was statistically significant for all rotations in first 4 weeks (P < 0.01). Negative correlation between time offshore and injury was observed in all schedules and consistent for age groups, categories of work, shifts and severity of injury. There was no difference in relative risk of injuries between the four schedules, when corrected for exposure and occupational risk of injury. Conclusions: These results are at variance with previous studies, although no prior study has looked beyond 3-week rotation schedule. Longer offshore schedules are safely possible and this could help decrease manpower and logistics costs for oil and gas companies coping with unprecedented low oil prices.

ADA Title I allegations and the Mining, Quarrying, and Oil/Gas Extraction industry.

BACKGROUND: The majority of research about employment discrimination in the U.S. Mining, Quarrying, and Oil/Gas (MQOGE) industries has concentrated on gender and race, while little attention has focused on disability. OBJECTIVE: To explore allegations of Americans with Disabilities Act (ADA) Title I discrimination made to the Equal Employment Opportunity Commission (EEOC) by individuals with disabilities against MQOGE employers. METHODS: Key data available to this study included demographic characteristics of charging parties, size of employers, types of allegations, and case outcomes. Using descriptive analysis, allegation profiles were developed for MQOGE's three main sectors (i.e., Oil/Gas Extraction, Mining except Oil/Gas, and Support Activities). These three profiles where then comparatively analyzed. Lastly, regression analysis explored whether some of the available data could partially predict MQOGE case outcomes. RESULTS: The predominant characteristics of MQOGE allegations were found to be quite similar to the allegation profile of U.S. private-sector industry as a whole, and fairly representative of MQOGE's workforce demographics. Significant differences between MQOGE's three main sector profiles were noted on some important characteristics. Lastly, it was found that MQOGE case outcomes could be partially predicted via some of the available variables. CONCLUSIONS: The study's limitations were presented and recommendations were offered for further research.

Development and validation of a new safety climate scale for petrochemical industries.

BACKGROUND: While a considerable body of research has studied safety climate and its role as a leading indicator of organizational safety, much of this work has been conducted with Western manufacturing samples. OBJECTIVE: The current study puts emphasis on the cross-validation of a safety climate model in the non-Western industrial context of Iranian petrochemical industries. METHODS: The current study was performed in one petrochemical company in Iran. The scale was developed through conducting a literature review followed by a qualitative study with expert participation. After performing a screening process, the initial number of items on the scale was reduced to 68. RESULTS: Ten dimensions (including management commitment, workers' empowerment, communication, blame culture, safety training, job satisfaction, interpersonal relationship, supervision, continuous improvement, and reward system) together with 37 items were extracted from the exploratory factor analysis (EFA) to measure safety climate. Acceptable ranges of internal consistency statistics for the sub-scales were observed. Confirmatory factor analysis (CFA) confirmed the construct validity of the developed safety climate scale for the petrochemical industry workers. The results of reliability showed that the Cronbach's alpha coefficient for the designed scale was 0.94. The ICC was obtained 0.92. CONCLUSION: This study created a valid and reliable scale for measuring safety climate in petrochemical industries.

Management and control of microbiologically influenced corrosion (MIC) in the oil and gas industry-Overview and a North Sea case study.

Microbiologically influenced corrosion (MIC) is the terminology applied where the actions of microorganisms influence the corrosion process. In literature, terms such as microbial corrosion, biocorrosion, microbially influenced/induced corrosion, and biodegradation are often applied. MIC research in the oil and gas industry has seen a revolution over the past decade, with the introduction of molecular microbiological methods: (MMM) as well as new industry standards and procedures of sampling biofilm and corrosion products from the process system. This review aims to capture the most important trends the oil and gas industry has seen regarding MIC research over the past decade. The paper starts out with an overview of where in the process stream MIC occurs - from the oil reservoir to the consumer. Both biotic and abiotic corrosion mechanisms are explained in the context of managing MIC using a structured corrosion management (CM) approach. The corrosion management approach employs the elements of a management system to ensure that essential corrosion control activities are carried out in an effective, sustainable, well-planned and properly executed manner. The 3-phase corrosion management approach covering of both biotic and abiotic internal corrosion mechanisms consists of 1) corrosion assessment, 2) corrosion mitigation and 3) corrosion monitoring. Each of the three phases are described in detail with links to recent field cases, methods, industry standards and sampling protocols. In order to manage the corrosion threat, operators commonly use models to support decision making. The models use qualitative, semi-quantitative or quantitative measures to help assess the rate of degradation caused by MIC. The paper reviews four existing models for MIC Threat Assessment and describe a new model that links the threat of MIC in the oil processing system located on an offshore platform with a Risk Based Inspection (RBI) approach. A recent field case highlights and explains the conflicting historic results obtained through serial dilution of culture media using the most probable number (MPN) method as compared to data obtained from corrosion monitoring and the quantitative polymerase chain reaction (qPCR) method. Results from qPCR application in the field case have changed the way MIC is monitored on the oil production facility in the North Sea. A number of high quality resources have been published as technical conference papers, books, educational videos and peer-reviewed scientific papers, and thus we end the review with an updated list of state-of-the-art resources for anyone desiring to become more familiar with the topic of MIC in the upstream oil and gas sector.

Optimization of a cloud point extraction procedure with response surface methodology for the quantification of dissolved iron in produced water from the petroleum industry using FAAS.

The characterization of inorganic elements in the produced water (PW) samples is a difficult task because of the complexity of the matrix. This work deals with a study of a methodology for dissolved Fe quantification in PW from oil industry by flame atomic absorption spectrometry (FAAS) after cloud point extraction (CPE). The procedure is based on the CPE using PAN as complexing agent and Triton X-114 as surfactant. The best conditions for Fe extraction parameters were studied using a Box-Behnken design. The proposed method presented a LOQ of 0.010µgmL-1 and LOD of 0.003µgmL-1. The precision of the method was evaluated in terms of repeatability, obtaining a coefficient of variation of 2.54%. The accuracy of the method was assessed by recovery experiments of Fe spiked that presented recovery of 103.28%. The method was applied with satisfactory performance to determine Fe by FAAS in PW samples.