Ergonomic Recommendations Research Articles

PECULIARITIES OF VISUAL PERCEPTION OF VISUALLY IMPAIRED CHILDREN

The author proved that limited opportunities in children manifest themselves in significantly limited life activities, which in turn significantly affect social maladaptation. A deep and comprehensive analysis is needed not only to understand modern experience in this field and successfully finda solution for this problem, but also to perceive the historical and pedagogical heritage of the past. Critical analysis of historical experience contributes to better understanding and eventual solving of the problems of modern typhlopedagogy. The concept "visually impaired"is described. The categories of these children are defined. It is characterized that amblyopia is understood as various forms of decreased visual acuity caused by functional disorders of the visual apparatus. It is established that the term "strabismus" combines lesions of the visual and oculomotor systems that are different in origin and localization, causing periodic or permanent deviation of the eyeball. The authors proved that amblyopia and strabismus, causing a decrease in visual acuity and visual functions, inevitably cause visual deprivation. It is proved that children with strabismus and amblyopia of monocular vision experience significant difficulties in determining the color saturation, shades and lightness of objects, the size of three-dimensional objects. It is established that this causes the impoverishment of the child's sensory experience, difficulty in orientation in space, disharmonious development of sensory and intellectual functions, which affects the development of visual-effective and visual-imaginative thinking. The author, in the course of analyzing psychological and correctional sources, concludes that the process of perception of educational material by students with visual impairments largely depends on the clinical picture of the visual defect, on the structural and functional disorders of this analyzer. It is determined that correctional and pedagogical work is organized and methodically directed depending on the functional disorders of vision (acuity, field, binocularity, gaze fixation, etc.), various ergonomic recommendations are determined by the author (visual, tactile, physical activity, illumination of the working surface of the table, etc.). The author proved that ICTs can become a significant factor of positive changes, because their application allows attracting more participants in education at a lower cost, meeting the requirements of social justice for all groups of the population, opens up broad prospects for improving the quality of education, its accessibility for people with special psychophysical development, contributing to equal access to information and educational services, full and fruitful social integration. Introduction of open access repositories with educational and scientific content will provide alternative ways of acquiring knowledge despite time or space constraints.

Finite element human hand model: Validation and ergonomic considerations

Established ergonomic practices incorporate only limited user data while designing new handheld products and hand tools. Design of handheld products and their handles relies mostly on ergonomic recommendations and designer experiences. Measurements of quantitative variables such as contact area, pressure, stresses, strains, etc. on hands using traditional methods are not possible or are time consuming, require a product prototype and expensive measurement systems. Therefore, companies do not incorporate these data in the product development, which could improve ergonomics further. To overcome this, we present a viable option of development and utilization of a finite element human hand model which allows grasping of products inside a virtual environment and provides quantitative results. The finite element human hand model is constructed based on medical images of a real human hand, with boundary conditions resembling the actual anatomical and topological features, which makes the model numerically feasible and biomechanically accurate. Results in terms of movement and grasping simulations of the finite element digital human hand model are presented with a discussion of the utilization of these results in the ergonomic design process.

Back Pain Prevalence, Intensity, and Associated Risk Factors among Female Teachers in Slovakia during the COVID-19 Pandemic: A Cross-Sectional Study.

Significant back pain prevalence and intensity are reported in female pedagogues. Due to the COVID-19 pandemic, they have been exposed to remote working conditions, higher psychological demands, and stress. Our objective was to evaluate the back pain prevalence, intensity, and related risk factors in female teachers from Slovak regions in the context of remote learning during the COVID-19 pandemic. An electronic questionnaire was applied for data collection. A total of 782 adult female teachers (age 43.11 ± 0.36, BMI 34.94 ± 5.94) from primary, secondary, and tertiary schools from Slovak regions were included in the survey. Of these, 74% reported cervical pain, 67% lower back pain, and 60% pain in more than one vertebral region. The highest pain intensities were reported in the following cohorts (pain scale 1–5, 1 = no pain, and 5 = extreme pain): pedagogues from the Presov region (3.74), those working in the special education sector (3.83), those who gave five online classes a week (3.58), those who performed no physical activity (PA, 3.86), pedagogues who did not work in compliance with ergonomic recommendations (3.59), those with moderate or severe stress (3.66), and those who were sitting all or most of the time (3.62). The main risk factors identified were: no PA performed, no compliance with ergonomic recommendations, and stress.

How the Intensity of Night Shift Work Affects Breast Cancer Risk.

Background—In 2019, the IARC concluded that “night shift work is probably carcinogenic to humans (Group 2A), based on limited evidence from human epidemiological studies and sufficient evidence of cancer and strong mechanistic evidence in experimental Animals.” The negative health consequences of night shift work may depend on how the night shifts are scheduled. The aim of this study was to investigate how the characteristics of night work affect the risk of developing breast cancer. Methods—A case–control study was conducted in 2015–2019 in the Lodz region. The case group included 494 women with breast cancer, while the control group included 515 healthy women. Results—Night work was found to be the third most important factor regarding breast cancer after a high BMI and a short or no breastfeeding period and before factors such as early menstruation, late menopause, no pregnancy, and smoking. The harmful effects of night work were influenced by its intensity, frequency, rotation, and the number of night shift years worked. Night work increases the breast cancer risk by 2.34 times, and high-intensity night work increases the breast cancer risk by 2.66 times. Conclusions—Appropriate ergonomic recommendations for night shift work for employers should be considered.

Ergonomic Recommendations in Ultrasound-Guided Botulinum Neurotoxin Chemodenervation for Spasticity: An International Expert Group Opinion.

Ultrasound (US)-guided botulinum neurotoxin (BoNT) injections are becoming a mainstay in the treatment of muscle spasticity in upper motor neuron syndromes. As a result, there has been a commensurate increase in US-guided BoNT injection for spasticity training courses. However, many of these courses do not emphasize the importance of ergonomics. This paper aims to highlight the importance of ultrasound ergonomics and presents ergonomic recommendations to optimize US-guided BoNT injection techniques in spasticity management. Expert consensus opinion of 11 physicians (4 different continents; representing 8 countries, with an average of 12.6 years of practice using US guidance for BoNT chemodenervation (range 3 to 22 years)). A search using PubMed, College of Physicians and Surgeons of British Columbia database, EMbase was conducted and found no publications relating the importance of ergonomics in US-guided chemodenervation. Therefore, recommendations and consensus discussions were generated from the distribution of a 20-question survey to a panel of 11 ultrasound experts. All 11 surveyed physicians considered ergonomics to be important in reducing physician injury. There was complete agreement that physician positioning was important; 91% agreement that patient positioning was important; and 82% that ultrasound machine positioning was important. Factors that did not reach our 80% threshold for consensus were further discussed. Four categories were identified as being important when implementing ultrasound ergonomics for BoNT chemodenervation for spasticity; workstation, physician, patient and visual ergonomics. Optimizing ergonomics is paramount when performing US-guided BoNT chemodenervation for spasticity management. This includes proper preparation of the workspace and allowing for sufficient pre-injection time to optimally position both the patient and the physician. Lack of awareness of ergonomics for US-guided BoNT chemodenervation for spasticity may lead to suboptimal patient outcomes, increase work-related injuries, and patient discomfort. We propose key elements for optimal positioning of physicians and patients, as well as the optimal setup of the workspace and provide clinical pearls in visual identification of spastic muscles for chemodenervation.

Prevalence of Work-related Musculoskeletal Symptoms among Dental Students at Ss. Cyril and Methodius University Dental School in Skopje

AIM: The aim of the study was to investigate the prevalence of work-related musculoskeletal problems in 3rd, 4th, and final year of study in Ss. Cyril and Methodius University Dental School.
 METHODS: All 3rd, 4th, and final year regular dental students were invited to take part in the study, which involved completing the extended Nordic Musculoskeletal Questionnaire. This questionnaire facilitates an assessment of troubles (ache, pain, or discomfort) with neck, shoulders, upper back, elbows, wrists/hands, low back, hips/thighs, knees, and ankles/feet.
 RESULTS: Out of a maximum possible number of 146 students, 116 agreed to participate and completed the questionnaire (33 males and 83 females). The response rate was 79.5%. The mean age of students was 22.6 years (SD = 1.52), ranging from 20 to 26 years. During the past 12 months, students have problems mostly with neck 48 (41.4%), upper back 43 (37.1%), and low back 43 (37.1%). Working hours/week was 12 h for 3rd year, 20 h for 4th, and 30 h for 5th-year students. There is a significant difference between the students from third study year with these from 4th and 6th study year regarding the neck (χ2 (2)= 6.46, p < 0.05), upper back (χ2 (2) = 7.38, p < 0.05), and low back (χ2 (2)= 13.79, p < 0.05).
 CONCLUSIONS: This study reported high prevalence of musculoskeletal symptoms among the dental students. Preventive measures and more ergonomic recommendations are indicated.

Analysis of physical and physiological workloads of nursing in the surgical center.

Operating room nursing professionals are exposed to different workload. It is necessary to recognize which situations resulting from their tasks interfere with the health of the professional. We aimed to identify the physical and physiological loads on operating room nurses and their impact on the health as well as trace ergonomic recommendations based on the literature and performed analysis. The is an exploratory, observational, descriptive research conducted in the surgical center of a university hospital between August 2017 and July 2018. Nursing staff of both genders who worked as transport professionals or room circulators were included in the study. Data collection in the OR went through stages of Ergonomic Workplace Analysis (EWA), through semi-structured interviews addressing the physical and physiological work issues and a worksheet of data collected from the observations of the practitioners' actions. The study included 20 nursing workers of both genders with an average of 17.33±12.58 years of work experience. The most reported problematic factors were: lack of material, staff pressure, patient transporting, employment legal status with the institution, and lack of communication among the practitioners. There was a physical effort during the activity and a high prevalence of workers with pain complaints, which justifies the investigation.

A Designer’s Perspective on Ankylosing Spondylitis and its Impact on Quality of Life

The onset of symptoms of Ankylosing Spondylitis (AS) generally occurs between 20-40 years of age, which is the most active stage of any professional. The onset of symptoms beyond the age of 50 is less than 4%, so the target population is relatively younger than most of the chronic cases. For some, the condition might not have any implication at all but for a majority, it compromises the quality of life. With limited to no cure, non-pharmacological interventions are one of the predominant treatment methods for AS. The paper explores the human factors involved in the long-term management of AS and provides ergonomic recommendations for minimizing the impact of AS on the patient and society. Probing into ideal working conditions for a general population suffering from AS. The workplace management and design specifically for an AS patient is the sought goal of the research.

Prevalence of Musculoskeletal Disorders and Analysis of Working Postures by OWAS among Saffron Harvesters

Background and purpose: Work-Related Musculoskeletal Disorders (WRMSDs) annually dismiss numerous afflicted workers to medical centers and also cause inefficiency among the workers. Given that Iran is one of the major saffron producers and exporters, and having many workers involved, the present study was conducted with the aim to determine the prevalence of musculoskeletal disorders and to analyze the postural conditions of saffron harvesters.
 Methods: In this cross-sectional study, 110 saffron-harvesters were randomly selected. The prevalence of WRMSDs was examined through the Nordic Questionnaire (The data were analyzed using SPSS Software, Version 21), and corrective measurements were determined for these postures through the OWAS postural analysis.
 Results: The results showed that the most compromised regions of any prevalent disorders were back (38%) and waist (31.6%). In the postural analysis, trunk (80%) and legs (13%) were among the corrective measurements of category II, and arms were at category I. In the analysis of combined postures, it was found that 46% of them were at corrective measurements of category II, and 31% were at category III.
 Conclusion: Regarding the Nordic Questionnaire’s results and its comparison with the OWAS postural analysis, it was concluded that it was of utmost importance to take corrective measurements to prevent the mentioned damages. Therefore, main ergonomic recommendations and a product-oriented design guideline were advised to correct the postures.

Incorporating Surgical Ergonomics Education into Surgical Residency Curriculum

Education on surgical ergonomics during residency training is lacking. This study aimed to determine the feasibility and impact of incorporating surgical ergonomics lectures into residency curriculum. A survey was distributed to 42 residents with questions regarding demographics, surgical factors, prevalence of musculoskeletal (MSK) symptoms, and awareness of ergonomic recommendations. The residents then received 2 lectures on ergonomics in surgery. A follow up survey was distributed to evaluate the impact of the lectures. Twenty-two residents completed the presession survey. Ninety-one percent reported MSK symptoms attributed to their training. Seventeen residents completed the follow up survey. All reported increased awareness of their own habits while operating and improved understanding of methods to prevent and/or treat work-related injuries. All residents recommended incorporating the lectures as an adjunct to their regular curriculum. The rates of MSK symptoms and/or injury are high among surgeon trainees. Residency is an opportune time to educate on principles of ergonomics and may prevent future injuries.

Analisis ergonomi pada perkuliahan daring menggunakan smartphone selama masa pandemi covid-19: studi kasus mahasiswa Prodi Teknik Industri Universitas Mulawarman

When Covid-19 emerged in Indonesia in early 2020, students had to learn from home to prevent the spread of the virus. The changing activity could effect on physical and mental health caused by student’s behavior during learning from home. Survey showed that 84% students of Industrial Engineering, Mulawarman University used smartphone while learning from home. Therefore, this study aimed to identify students’ behavior, to measure physical (i.e., musculoskeletal and visual fatique) and mental health (i.e., stress and smartphone addiction) problems that occurred when they were learning from home, as well as to suggest ergonomic recommendation for reducing the negative effects. At the time of the study, they were 155 students studied in the IE department and a total of 134 (86.45%) participated in the online survey. Musculoskeletal disorder was assessed using Nordic Body Map and visual fatique was evaluated using symptoms that were reported on previous studies. Additionally, Smartphone Addiction Scale (SAS) and Perceived Stress Scale (PSS) were administered to identify smartphone addiction tendency and stress level respectively. The results showed that MSD occurred in left and right shoulder (95%), followed by upper neck (82.14%) and back (72.62%). 86% of participants experienced visual fatique with headache (71.55%), ache eye (68%) and dry eye (60.34%) symptoms. Subsequently, this survey revealed that 35% of the participants addicted to smartphone and 68.66% experienced moderate level of stress. To alleviate these physical problems, several ergonomic recommendations were proposed i.e., supporting the arm that holding the smartphone with the other hand, practicing the 20-20-20 rule and applying stop, drop and flop slogan. Moreover, cooperation among parents, students and lecturers was needed to create conducive learning environment so as the mental health problems could be minimized.

Impact of COVID-19Quarantine on Low Back Pain Intensity, Prevalence, and Associated Risk Factors among Adult Citizens Residing in Riyadh (Saudi Arabia): A Cross-Sectional Study.

This study aimed to estimate the effect of the coronavirus disease 2019 (COVID-19) quarantine on low back pain (LBP) intensity, prevalence, and associated risk factors among adults in Riyadh (Saudi Arabia). A total of 463 adults (259 males and 204 females) aged between 18 and 64 years and residing in Riyadh (Saudi Arabia) participated in this cross-sectional study. A self-administered structured questionnaire composed of 20 questions regarding demographic characteristics, work- and academic-related aspects, physical activity (PA), daily habits and tasks, and pain-related aspects was used. The LBP point prevalence before the quarantine was 38.8%, and 43.8% after the quarantine. The LBP intensity significantly increased during the quarantine. The low back was also the most common musculoskeletal pain area. Furthermore, during the quarantine, a significantly higher LBP intensity was reported by those individuals who (a) were aged between 35 and 49 years old, (b) had a body mass index equal to or exceeding 30, (c) underwent higher levels of stress, (d) did not comply with the ergonomic recommendations, (e) were sitting for long periods, (f) did not practice enough physical activity (PA), and (g) underwent teleworking or distance learning. No significant differences were found between genders. The COVID-19 quarantine resulted in a significant increase in LBP intensity, point prevalence, and most associated risk factors.

Musculoskeletal pain amongst Australian sonography students and recent graduates and an evaluation of the use of ergonomic education for prevention.

Sonographers develop pain whilst scanning and may not consistently adhere to ergonomic recommendations. The aim was to quantify this within Australian sonography students and recent graduates and to determine whether a relationship exists between: (i) pain and failure to adhere to ergonomic recommendations; and (ii) theoretical and practical ergonomic education during university and clinical placement, and the adherence to recommendations. Online questionnaire distributed to Australian student sonographers and sonographers until two years post-graduation. During scanning, 33/39(84.62%) experienced musculoskeletal pain, and 21/33 (63.64%) experienced pain less than 1.76 full-time equivalent (FTE) days during the two FTE week period. The majority, 37/39 (94.87%), were not consistently adhering to recommendations, with 25/37 (67.57%) only doing so for less than 2.1 FTE days during two FTE weeks. Failure to adhere to ergonomic recommendations and development of musculoskeletal scanning pain was positively correlated (r=0.7 (P=0.01)).All participants had received some form of ergonomic education. This education was theoretical and practical during university and clinical placement for 24/39 (61.54%); however, receiving this resulted in no difference for adherence to ergonomic recommendations. Qualitative data demonstrated high workloads, scanning patients with increased body habitus or limited mobility were potential barriers to adherence to ergonomic recommendations. Ergonomic education occurs, yet a lack of knowledge and adherence to recommendations continues. Considerations for other potential barriers are required. Ensuring students adhere to ergonomic recommendations post-graduation and identifying relevant barriers within the clinical environment are important. Future research to investigate potential barriers around ergonomic adherence is suggested.

Social Climate and Classroom Adaptations for Blended Learning Practices

Spatial conditions influence social relations and the development of cultural bonds inside a building. The traditional configuration of most school classrooms must be reconsidered to allow for changes in the educational paradigm to support ICT for learning. It is not clear which environmental aspects should be modified to improve performance in physical learning environments (LE), especially to accommodate hybrid models in classrooms. This article describes the process used to understand education conditions for attending to student needs, the connection between the LE, new technologies, and a social climate favourable to educational changes. This study was carried out in a public secondary school in North-eastern Brazil and adopted a design science research method to perform a participatory design exercise, to develop new classroom environment concepts. The results suggest a set of guidelines for LE suitable for active learning methods, considering activities modalities and environment quality criteria, focused on positive social climate conditions and on ergonomic recommendations.

Interaction with a smartphone under different task and environmental conditions: Emergence of users’ postural strategies

Nowadays, interactions with smartphones are constantly increasing. These devices are used in a wide variety of situations by performing various tasks. The purpose of this study is to determine whether one or more strategies emerge when subjects freely send message and browse on the web in three environmental conditions: sitting with or without support and standing. Therefore, a hierarchical cluster analysis (HCA) was applied to the angular parameters of the neck and trunk as well as to the distance between the face and the telephone. These 3D motion analysis data were also processed taking into account the ergonomic recommendations from the Rapid Upper Limb Assessment in order to qualify the postural strategies highlighted by the HCA. The findings showed that there are three different postural strategies adopted by the subjects especially in the sagittal plane: a first one involves the neck without implying the trunk; a second one strongly mobilizes the trunk flexion without involving the neck; and a third postural strategy which combines these two behaviors. These three postural strategies depend on the environmental condition. Indeed, the postural strategy involving the trunk is associated with the presence of a support while the one involving the neck only appears in conditions without support. It is also observed that smartphone users mainly adopt harmful postures, whether due to excessive flexion of the neck, trunk or both. Even when subjects place themselves in the least harmful postures, there are always risks of musculoskeletal disorders in the short or long term.

Desenvolvimento da AET quando o trabalho prescrito não está claro: o caso de uma indústria alimentícia

A Ergonomia vem alcançando atenção ao contribuir em melhorias no setor alimentício, principlamente na obtenção de ambientes mais adequados, confortáveis e seguros. Neste contexto, o presente objetiva apresentar a aplicação de uma Análise Ergonômica do Trabalho (AET) em uma indústria de alimentos no extremo sul do Brasil. Para isso, buscou-se primeiramente apoio téorico para compreender o cenário estudado. A seguir, foi desenvolvida uma AET considerando o caminho metodológico proposto por Iida e Guimarães (2016). Os resultados permitiram identificar desafios importantes para a empresa, principalmente no tocante à Ergonomia Física e Ergonomia Organizacional. As ações de melhoria de menor investimento financeiro foram propostas e implementadas, contribuindo em vários pontos, integrando melhoria do conforto do trabalhador concomitante à maior eficiência do processo. Investimento mais onerosos e complexos foram direcionados para discussões posteriores no âmbito da gerência da empresa e fora do escopo de abrangência do presente trabalho.

Road ambulances: working conditions of paramedics - pilot studies.

The article presents the results of selected pilot studies conducted in medical ambulances. Their aim was to determine the working conditions and identify troublesome factors accompanying the performance of basic medical procedures by rescue teams. The study of working conditions was carried out in Mercedes-Benz ambulances, type S and P. Fifty-one paramedics of the Emergency Medical Rescue Service in Siedlce took part in the research. The questionnaire expert survey method and the direct observation method were used. As a result of the applied research methods, knowledge was gained on the irregularities and difficulties that occur at the workplace of a paramedic, i.e., in an ambulance, including the lack of access to essential elements of medical equipment and their different location inside the vehicle, and the diversity of solutions for the spatial structure of ambulances, which all cause difficulties at work. Research has shown that paramedics take, on average, 33 min to familiarize themselves with the location of equipment in an ambulance other than the one in which they are usually on duty. There was no correlation between the lifeguard's length of service and the time necessary for getting acquainted with the equipment, which was studied using Pearson's correlation coefficient. In the study, rescuers also pointed to musculoskeletal ailments, mainly spinal pains resulting from taking forced positions during medical activities in an ambulance. The results obtained constitute the basis for the author's methodology of complex research aimed at defining the ergonomic recommendations necessary in the modification process of the operated medical fleet. The next step will be to formulate uniform guidelines for the construction of medical compartments of ambulances, the application of which will lead to the unification of their spatial structure regardless of the vehicle brand. Int J Occup Med Environ Health. 2020;33(1):91-105.

Ergonomic Recommendation of Suitable Toilet Seat Height for Older Thai People

Objective: This study aimed to determine the main factors affecting older people as they rise from a toilet seat and to identify the suitable toilet seat height for this population.Material and Methods: Data from 342 older people both male and female aged 60 years and older were used to design a mock-up toilet with a specified seat width according to the 95th percentile of hip breadth. The data of lower leg length were used to design toilet seat height levels in the second phase in another 30 older participants at 100.0%, 110.0% and 120.0% of an individual’s lower leg length (LLL). Rectus femoris and gluteus maximus muscle activity, time taken while rising, pressure under the thighs and satisfaction of the older participants were compared across three toilet seat height levels; using the repeated analysis measurements of variance. These three potential factors were then analyzed together with the prioritized factor indicated by the specialists using the Analytic Hierarchy Process.Results: Rectus femoris muscle activity, time taken while rising, and satisfaction of the older participants in rising from toilet seat heights 100.0, 110.0 and 120.0% LLL were significantly different (p-value<0.05).Conclusion: It was found that the suitable toilet seat height level for older people for industrial ergonomic purposes was at 110.0% LLL, which was also equivalent to the 95th percentile of male and female LLL.

Activity in neck-shoulder and lower arm muscles during computer and smartphone work

Relevance to industryThere is emerging evidence of musculoskeletal problems related to smartphone work and a rapid transition to mobile workplaces, where smartphones are key working tools. Aim: The study's aim was to compare muscle activity during computer work with smartphone work and to see what possible effects ergonomic recommendations for smartphone usage have on muscle activity. MethodsActivity was measured bilaterally from the upper trapezius muscle and from lower arm muscles on the right hand side, on twelve participants with surface electromyography who performed e-mail work on the computer using ergonomic recommendations, smartphone in a self-chosen way of working and on smartphone with ergonomic recommendations. Effects on productivity was not assessed in this study. ResultsActivity in m. trapezius and m. extensor digitorum was significantly higher during computer work (p < 0.05) than during the two smartphone usages and activity in m. interossei dorsalis 1 was, vice versa, significantly higher during smartphone work (p < 0.05). Comparison of smartphone in self-chosen way of working and smartphone with ergonomic recommendations showed no significant differences. ConclusionsPrevious research has highlighted the benefits of variation of work postures. This paper indicates that replacing the computer with a smartphone gives the trapezius muscle an opportunity to rest.

Effects of color codes used on marine supervision HMI on mental workload and information retrieval: Experimentations with novices and experts

Using a color code on human-machine interfaces could sensibly reduce the informational density. In this paper, we focused on the supervision interfaces used in engine room of Merchant Navy vessels. There is no regulation about color use on these interfaces, despite the color code playing an important role in showing information. The ISO Standard 14726-2008 regulates the color code printed on physical pipes and is used to represent the fluids flowing through it. The purpose of this study is to determine if we could use this standardized color code on the interfaces and create a connection between the physical pipes and their graphical representation. Two experimentations are presented, in which we compared the effects of two color codes on the performance at searching tasks carried out by novices and experts. One code is extracted from ISO Standard 14726-2008 (Normative Pipe Identification Color Code), and the other is created by taking into account general guidelines and common uses (Ergonomic Recommendations Color Code). The results showed that the NPICC, and its bicolor version in particular, increased the mental workload and the searching time required by novices. Experts had more difficulties to recognize the fluids represented by two colors and they used the two-colored fluid system less frequently than novices to retrieve an information.