Abstract The need for dressings on clean and clean contaminated surgical wounds was investigated. A total of 1202 patients with 1202 clean or clean contaminated surgical wounds were randomized into two groups: 633 wounds were covered by dressings up until the time of suture removal, and 569 wounds were treated without dressings after the first postoperative day. In the group characterized by long dressing time, the rate of postoperative wound infections was 4·9 per cent. The rate was 4·7 per cent in the group represented by short dressing time. Using short dressing time not only reduces the number of nursing hours but also limits the need for costly dressing material. In addition, both wound observation and patients' personal hygiene are made easier.