Visual demand, visual ability and vision standards for hairdressers - An observational study from Chennai, Tamil Nadu.

Purpose: The aim of this study was to create vision standards for various tasks performed by hairdressers and to assess the spectacle compliance and its impact at work. Methods: The observational cross-sectional study enrolled hairdressers in and around Chennai, Tamil Nadu. It was done in three phases: (i) Job profiling from visual task analysis, creating vision standards for various hairdressing tasks and arriving at test protocols; (ii) Comprehensive eye examination, and (iii) Assessment of spectacle compliance and its impact on work. Descriptive analysis using Microsoft Excel and SPSS (IBM SPSS Statistics Version 21.0) was performed. Results: There were 305 participants with a mean age of 48 (SD ± 12) years. The visual acuity demand was found to be 6/18 and N15, for distance and near, respectively. Appropriate spectacles were prescribed for 203 (67%) hairdressers. Even with the best possible refractive correction, a few hairdressers did not meet the distance (13) and near (11) visual acuity standard. In all, 54 hairdressers were referred for further examination to a tertiary eye care center for lenticular changes, retinal abnormalities, and glaucoma screening. Among the subjects who were dispensed with spectacles, 181 (86%) were available for telephonic spectacle compliance assessment, and 164 (90%) were compliant with spectacle usage at work. Improved visual ability was reported by 133 (81%) hairdressers at work. Conclusion: This study provides vision standards for hairdressers. From the visual task analysis, hairdressing tasks were found to be visually demanding and hazardous. The study emphasizes that providing appropriate spectacle correction showed a clinically evident positive impact at work.

Visual functions of workers exposed to organic solvents in petrochemical industries.

AIM: The purpose of this study was to evaluate the visual functions of workers exposed to organic solvents in petrochemical industries. MATERIALS AND METHODS: Thirty workers from the petroleum refinery and 30 age-matched controls (mean age) were recruited. Visual functions and occupational exposure levels were assessed among both the groups. Visual acuity, contrast sensitivity, color vision, and visual fields were evaluated at the workplace. The biological samples, namely blood and urine, were collected at the workplace and transported to the laboratory for analysis. The urinary excretion of hippuric and methylhippuric acid as well as creatinine was measured by high performance liquid chromatography. RESULTS: The mean age of the workers and controls were 39.7 ± 7.6 years and 38.6 ± 8.1, years respectively. The mean years of experience of the workers were 15.6 ± 6.8 years. Visual acuity was >0.01 LogMAR among both the control and case groups. The contrast sensitivity was reduced at 12cpd among workers. Comparison between groups was done using independent sample t-test. The mean difference in color confusion index was 0.11 ± 0.05 (P = 0.037*). The mean difference in visual fields was -0.31 ± 0.36 dB (P = 0.933). The mean difference in urinary hippuric acid level (urinary metabolite of toluene) between the groups was 0.19 ± 0.96 g/g creatinine (P = 0.049FNx01). The mean difference in the excretion of methylhippuric acid (urinary metabolite of xylene) was 0.06 ± 0.04g/g creatinine (P = 0.154). We also found that exposure was a significant risk factor for color vision defect with an odds ratio of 4.43 (95% CI: 1.36-14.4); P = 0.013. CONCLUSION: The study results showed that contrast sensitivity and color vision were affected among workers in petrochemical industry.

Establishing pre-employment vision standards for goldsmiths.

BACKGROUND: The process of jewellery making involves the goldsmiths working with tiny visual tasks at closer working distances, which demands high visual ability. AIM: To establish vision standards for Goldsmiths. MATERIALS AND METHODS: Visual task analysis was carried out in different Goldsmith workstations. The minimal visual demands of the jobs were determined based on Grundy's nomogram. Depending on the importance of certain visual functions to perform the job, criteria for visual competency was laid down. Visual abilities of goldsmiths were evaluated in order to determine their visual capability status, based on the previously laid criteria. Job competency status of goldsmiths was determined based on the supervisors' grading with respect to the quality and quantity of work. Visual competency and job competency of goldsmiths were then compared in order to establish vision standards. RESULTS: Visual task analysis was carried out in 91 workstations. The median of working distance, work area, critical size of the task, and illuminance were 23 cm (IQR: 20- 29), 514.5 Sq Cm (IQR: 183-746.5), and 536.5 lux (IQR: 170-536.5), respectively. Visual abilities of 113 goldsmiths were evaluated. 44.7% of goldsmiths were found to be visually competent. Job competency status of 30 goldsmiths was obtained, in which 18 (60%) were found to be highly job competent. Based on the visual demands, vision standard for jewellery makers was developed. CONCLUSION: The vision standards so obtained could be used as minimum visual requirements for the entry level Goldsmiths.