روشنایی مصنوعی

Given that optimal workplace lighting plays a crucial role in mitigating visual strain, enhancing productivity, and improving overall employee performance, the present study sought to evaluate the current lighting system within a repair workshop. Additionally, it aimed to explore the feasibility of proposing tailored strategies for achieving optimal lighting conditions through specialized tools, such as DIALux software.

In this cross-sectional study, the work environment was examined, and lighting measurements were carried out at 35 stations. According to national standards, various executable solutions considering the existing lighting system and fixtures were evaluated to achieve an illumination intensity of 300 lux and a uniformity index of 0.6 in the workhouse. Moreover, the software's capabilities were used to predict the impact of each solution on improving illumination intensity and uniformity index.

The average illumination intensity in the repair workhouse was 290 lux with a uniformity index of 0.3. According to these results, the workhouse's lighting system needed improvement. The results indicated that software-provided solutions could increase illumination intensity to between 300 and 804 lux and improve the uniformity index to between 0.32 and 0.58.

The results revealed that significant changes and improvements in the workhouse's lighting can be achieved by implementing simple and low-cost solutions. In addition, the use of specialized lighting software by experts can lead to reliable and feasible solutions for enhancing lighting systems.

Visual comfort is an important and influential factor on safety, mental health, sleep quality, and musculoskeletal disorders of employees in the workplace. This study aimed to design and develop a questionnaire to assess the visual comfort of employees in the workplace.

The study was performed on 101 participants (88 men and 13 women) in the food industry. First, the available lighting questionnaires in the field of lighting were reviewed, and a question bank was collected. Twenty questions were considered in two sections of natural and artificial lighting (10 questions in each section) based on the opinion of 10 experts in this field. The validity of the questionnaire was assessed using the content validity index (CVI) based on the comments of experts. To validate the questionnaire in the workplace, The lighting of employees' workstations was evaluated according to the Illuminating Engineering Society of North America (IESNA) standards and compared with the results of the questionnaire.

The Cronbach's alpha of natural and artificial lighting visual comfort questionnaire was 0.858 and 0.922, respectively. The total CVI of the questionnaire was 1. There was a significant positive relationship between the score of the visual comfort questionnaire and the workstations' illumination (P=0.001). More than 97% of employees who had workstations with the desired lighting reported excellent levels of visual comfort.

The visual comfort questionnaire had good and acceptable reliability and validity. This tool is recommended to assess the visual comfort of employees in work environments due to the small number of questions and simplicity of sentences.

Inadequate lighting in the workplace can cause unconventional changes in the posture of office workers. Poor ergonomic conditions in the office cause inappropriate postures during work and increase pressure on the musculoskeletal system which can cause some disorders in long-term. In this study, the relationship between work environment lighting with the prevalence and severity of musculoskeletal pain among office workers has been investigated.
In this study, the intensity of local illumination at work surface and at the perpendicular surface (perpendicular surface to the work surface and at the height if workers eye), and intensity of general lighting was measured based on the standard of The Illuminating Engineering Society (IES) using the SEKONIC, C-7000 SpectroMaster. Also, to assess the prevalence and severity of pain of musculoskeletal disorders, a Nordic Questionnaire, Body map index were used respectively. To assess the office work strain, Rapid Office Strain Assessment techniques (ROSA) were used. Data were analyzed by SPSS software version 21.
The results showed that the average intensity of general lighting, local lighting at work surface and at the perpendicular surface was 30.6%, 33.9%, and 38.4% lower than required illumination intensity of Occupational Exposure Limits (OEL). The neck and waist had the highest prevalence of the musculoskeletal disorder among the workers. The highest frequency percentage of scores in the ROSA method related to scores 5 (41.7%) which had a significant correlation with illumination intensity.
illumination intensity can be considered as one of the important factors affecting posture in administrative staff. Therefore, the improvement of illumination intensity can decrease the severity of musculoskeletal pain and improve the body postures of the staff and, consequently, increase their comfort.

The comfort lighting in the workplace provides employees visual health which can improve safety، visual comfort and enhance performance and product quality. The present study was conducted to evaluate general and local lighting in carpet weaving workshops in Bijar city.

In this descriptive analytical study، 101 carpet weaving workshops were randomly selected. The illuminance were measured based on the models and formulas presented in Illuminating Engineering Society (IES) using luxmeter model Hagner EC1 in height 76 cm from the ground surface. The local illuminances were measured in horizontal and vertical weaving level. Data were analyzed by SPSS software (version 16).

Research findings revealed the average of total and artificial illuminance level were 484. 5±458. 9 and 80. 0±49. 9 Lx respectively. Mean total، natural and artificial illuminance 39. 6، 57. 4 and 100 percent were lower the recommended 300 Lx levels. The average of minimum of local illuminance was less than 500 Lx in all workshops.

About 60% of workrooms had the acceptable general illuminance levels in middle day. However، due to the insufficient lighting sources in workshops، the artificial illuminance levels are unsuitable. Therefore، it is necessary to improve general illuminance levels by reform and repair artificial lighting systems or redesign them in carpet weaving workrooms.