In order to improve the ladders used in apple cultivation from the viewpoint of human engineering, the kinds of ladder used in the Tsugaru area and the fatigue condition when using these ladders were investigated by means of a questionnaire. The author received answers from 196 houses (281 people) and obtained the following conclusions.
1. The ladders most frequently used in apple cultivation are made of wood, are about 200cm long, and are sold on the market ; the second most frequently used type is 233 cm long. There was no variety in using condition, though the geographical features of the terrain were different.
2. Most people used rubber boots on the ladder. More of them complained of fatigue in the back parts of legs than in the front parts.
3. 36 % of the men and 24 % of the women felldown from the ladder at least one year during apple cultivation. The incidence was higher for people in their twenties, but the rate decreased as the age increased, to increase again for people in their sixties.
4. The three main suggestions for improvement are to make the ladder lighter, to deepen the surface of the rungs and to make the whole design sturdier.