Noise-induced hearing loss (NIHL) is a high frequency sensory-neural hearing loss and exposure to traffic noise by traffic policemen makes them susceptible to develop NIHL. The objective of this study was to determine the prevalence and correlates of NIHL among traffic policemen in the city of Colombo, Sri Lanka. A cross sectional study was carried out using 350 traffic policemen who are working in the city at least six months of duration. Pure-tone audiometry test and interviewer-administered questionnaire were used to assess hearing and correlates of NIHL, respectively. The chi-square test and logistic regression was used to analyze the relationship between risk factors and NIHL.287 policemen attended pure-tone audiometry test to check their hearing. Of 287 subjects, the prevalence of NIHL was found in 118 policemen (41%; 95% CI: 36%-47%). Of those with any type of NIHL, 33% (39/118) had major NIHL while 67% (79/118) had minor NIHL. In bivariate analysis 23 variables showed statistically significant association with mild and major NIHL. Multivariate logistic regression modelling found statistically significant association between "duration of employment as a policeman" and any type of NIHL (OR = 1.007; 95% CI = 1.005-1.009), adjusted for 23 variables including age. The prevalence of NIHL among traffic policemen in the city was high. Of those with any type of NIHL, one-third had major NIHL. Traffic policemen should undergo periodic hearing assessment. The police department should explore the feasibility of reducing the number of hours per day spent on the road by traffic policemen.

In this paper, an analysis of temporal variation of wind speed and wind direction recorded at 10 min intervals are presented. The measurements were carried out at Hambanthota, a site located in the southern coastal belt of Sri Lanka which has a high potential for wind power generation. The multifractal detrended fluctuation analysis was used to analyze the temporal scaling properties of wind speeds and wind directions. The analysis was carried out for seasonal variation of wind speed and wind direction. It was observed that the scaling behavior of wind speed in Hambanthota is similar to the scaling behavior observed in previous studies which were carried out in other parts of the world. The seasonal wind and wind direction change exhibits different scaling behavior. No difference in scaling behavior was observed with heights. The degree of multifractality is high for wind direction when compared with wind speed for each season.

Traffic noise levels in most cities of the world are higher than the recommended levels. Exposure to high levels of noise may cause adverse health effects such as ischemic heart diseases and noise induced hearing loss. We conducted a cross-sectional study to determine road traffic noise levels at 60 selected locations in the city of Colombo, Sri Lanka. On randomly selected days we measured equivalent continuous sound pressure level (LA eq ) for six hours during the day. From these measurements LA eq for eight hours were calculated and used as the average noise level of a particular location. LA eq (8 hrs) within Colombo ranged 76.6 to 84.0 dB; well above the Sri Lankan recommendation of 63.0 dB (an increase of 13.3 to 21.0 dB), and the WHO recommendation of 55.0 dB (an increase of 21.6 to 29.0 dB). These levels translate into increase of sound pressure level by 21.4 to 794.3 times above the recommendations on the logarithmic scale of dB. Thirty-eight of 60 locations recorded levels more than 80.0 dB. Road traffic noise levels in Colombo were well above the recommended levels. Though the increase in measured decibels might not appear to be too high, in reality this translates into an increase manifold times in the sound pressure level that reaches the ear.

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