5°C-water 10-minute immersion test, generally used in Japan, is useful to diagnose vibration diseases. But severe pains during the immersion is troublesome. We strdied the availability of 10°C-water 10-minute immersion test to reduce the pain during the test. Subjects were forty-nine chainsaw operators, nineteen patients with vibration disease, and twelve controls. The same subject underwent both 5°C and 10°C immersion tests. The following results were obtained. 1) Skin temperatures in the highest score group after the immersion tests both at 5°C and 10°C was lower than that in the control group. Mean skin temperatures for the last five minutes during the immersion and the recovery activity in both the immersion tests showed a similar trend among subjects groups. Skin temperatures in patients under medical treatment (R'group) did not differ from those in the control group. 2) Hyperemia time by nail press test in the R'group and in the high score group after both immersion tests was longer than that in the control group. But this difference between chainsaw operators and the control group after 5°C immersion test was more marked than that after 10°C immersion test. 3) Vibratory sense as well as pain sense in the R'group and in the high score group after both immersion tests were less sharp than those in the control group. 4) Skin temperatures, nail press test, vibratory sense, and pain sense after 5°C immersion test and those after 10°C immersion test showed statistically significant positive correlation. 5) 10°C immersion test is as effective as 5°C immersion test in finding nervous disorders, but 5°C immersion test is more effective than 10°C immersion test in finding circulatory disorders. However patiens with Raynaud's phenomena or moderate circulatory disorders can also be found even by 10°C immersion test. 6) Cold water immersion test revealed disorders not only in skin temperature and by nail press test but revealed also disorders in vibratory sense and pain sense, therefore it is desiable that cold water immersion test should be done in the examination of vibration diseases.
