Abstract
The sleeveless ventilated jacket "eco-jacket" for businessmen in hot summer was developed, which has two long side openings so that ventilation may be promoted. From the view point of the fashion the jacket was proved to be reasonable and acceptable. Experiments on the thermal environment from 25 to 28 degree C were carried out. Sweat rate at the back and the forearm, mean skin temperature and others were observed. Based on the results of the experiments the increasing ratio was defined for every item. An expression of the summer heat endurance for the jacket was given using the increasing ratio. The value of the summer heat endurance for the sleeveless ventilated jacket was estimated 1.5 times as superior as one for the ordinary jacket with long sleeves.
