OBJECTIVETo compare the results of noise hazard evaluations based on area sampling and personal sampling in a new thermal power plant and to analyze the similarities and differences between the two measurement methods.

METHODSAccording to Measurement of Physical agents in Workplace Part 8: Noise(GBZff 189.8-2007), area sampling was performed at various operating points for noise measurement, and meanwhile the workers under different types of work wore noise dosimeters for personal noise exposure measurement. The two measurement methods were used to evaluate the level of noise hazards in the enterprise according to the corresponding occupational health standards, and the evaluation results were compared.

RESULTSArea sampling was performed at 99 operating points, the mean noise level was 88.9 ± 11.1 dB (A)(range, 51.3-107.0 dB (A)), with an over-standard rate of 75.8%. Personal sampling was performed (73 person times),and the mean noise level was 79.3 ± 6.3 dB (A), with an over-standard rate of 6.6% ( 16/241 ). There was a statistically significant difference in the over-standard rate between the evaluation results of the two measurement methods ( x2=53.869, ?<0.001 ).

CONCLUSIONBecause of the characteristics of the work in new thermal power plants, the noise hazard evaluation based on area sampling cannot be used instead of personal noise exposure measurement among workers. Personal sampling should be used in the noise measurement in new thermal power plant.

Environmental Monitoring ; methods ; Environmental Pollutants ; analysis ; Microchip Analytical Procedures

Environmental Monitoring ; methods ; Noise, Occupational ; statistics & numerical data

OBJECTIVETo study the environmental changes of new snail habitual by using multi-temporal relative radiometric normalized TM images taken in Wuzhoutou of Nanchang, Jiangxi province.

METHODSTM images of Poyang Lake were collected on 3rd April 1998, 16th April 2000 and 5th May 2004. Taking images in 2004 as a reference, the TM images in 1998 and 2000 were radiometric normalized. The images were analyzed to trace the vegetation background and snail historical information.

RESULTSThe vegetation coverage rate of Wuzhaoutou on April 3rd in 1998 was 4.76%, but the vegetation coverage rates of Wuzhoutou on April 16th in 2000 and May 5th in 2004 were above 80%; the NDVI values of Wuzhoutou on April 3rd in 1998 were around -0.4 to 0.2, but the NDVI values of Wuzhoutou on April 16th in 2000 and May 5th in 2004 were mainly around 0.2 to 0.6, which had statistical difference with that in 1998 (q = 162.285321, P < 0.01 and q = 161.669725, P < 0.01). The greenness of three images have statistical differences(q = 178.679245, P < 0.01; q = 130.320755, P < 0.01 and q = - 48.358491, P < 0.01).

CONCLUSIONCombining with the snail survey, the TM images could be an effective measure for setting up models to forecast the areas where snails might live to control the Schistosomiasis epidemic.

Animals ; Environmental Monitoring ; methods ; Geographic Information Systems ; Snails

Dust ; analysis ; Environmental Monitoring ; methods ; Silicon Dioxide ; analysis

Air Pollutants, Occupational ; analysis ; Dust ; analysis ; Environmental Monitoring ; methods ; Workplace

Air Pollutants, Occupational ; analysis ; Dust ; analysis ; Environmental Monitoring ; methods ; Workplace

Air Pollutants ; analysis ; Environmental Monitoring ; methods ; Esters ; analysis

Environmental Monitoring ; methods ; Inhalation Exposure ; Occupational Exposure ; analysis ; Workplace