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The relationship between the degree of eye fatigue resulting from visual work and type of light source used to illuminate the field of work was assessed. The tests were performed using artificial light sources: fluorescent lamps, incandescent lamps, high pressure mercury (vapour) and high pressure sodium (vapour) lamps. The assessment was performed on two groups of 10 women each, of which one included women without, and the other with, refraction errors. On the basis of changes of nearer vision point and dispersing lens tolerance, it was found that sodium light produced the highest visual fatigue in the test women, especially in those with refraction errors.

Six cases of argyrosis diagnosed in workers silver-plating radio sub-assemblies have been presented. The patients had grey skin, especially of their faces, hands, mucous membrane of oral cavity, conjunctivae, cornea, and silver deposits in lenses. The clinical examination showed no deviations in the health status, apart from slight, determination in sight adaption to darkness in four subjects. No silver was found in the patient's blood and urine.

The examinations have been carried out under model conditions in women aged 33.6 +/- 3.8, in whom refraction defects or other sight organ disorders had been excluded. In order to select factors that would be most sensitive and specific for evaluation of visual fatigue, variations in the following indices of the sight organ occupational condition have been analysed: the near vision point, dispersing lens tolerance, retina sensibility, critical fusion frequency, speed and accuracy of perception, visual simple and choice reaction time. The indices have been analysed under the performance of sigh work and medium-hard physical effort. Variations in the near point and retina irritability have been regarded the most sensitive and specific indices of asthenopia. In addition, intra- and interpersonal variability, as well as seasonal variability of the indices listed have been assessed. Significant seasonal differences have been found between the values measured in the persons prior to work in summer and winter for near vision sense point, dispersing lens tolerance, retina irritability, and critical fusion frequency.

The results of all the efforts made so far towards the reduction of CS2 concentrations at the workplaces of viscose rayon industry indicate that achievement of safe standards is little probable in the nearest future. Likewise, the preventive activities aimed at the reduction of the daily working time from 8 to 6 hours and referring workers to work with no exposure for several months are hardly effective. Basing on the results of clinical and epidemiological studies of the CS2 exposed population and relevant control groups the authors indicate their own solutions of decreasing the health risk. Pursuant to this suggestion the total time of work in exposure should not exceed 15 years and would be interrupted by so called periods of "health regeneration", consisting in the transfer to the production with no CS2 exposure for one year. This rotational system would apply to all those employed for over five years under CS2 concentrations exceeding the hygienic standards.

The deficiency of binocular vision calls for an absolute contraindication to perform a number of occupations. It is not easy to evaluate the binocular vision disturbance, especially in young people. Therefore it was decided to check the binocular vision by six methods and compare the results. Among 199 pupils of the seventh form of primary schools, the following binocular vision disturbances have been found: in 18% of subjects on stereometer, in 15% on a projector with polarizing glasses, in 14% lack of protective reflexes, in 13% on stereoscope, in 11,6% on synoptophore and lack of ambiopia after using the prism in 9% of subjects. All the tests yielded negative findings in 5,5% of subjects. The obtained data suggest that it is not enough to use just one method for a thorough determination of binocular vision.