Introduction: As part of an effort to enhance the efficiency of workers, experiments relating to three types of noise exposure were conducted. Previous studies have proved that pink noise can cause a brain wave to reach a lower potential. In this study, we utilized physical methods, in cognitive experiments, to understand the impacts that three colour noises have on working efficiency.

Subjects and methods: All 22 participants were exposed to a sound environment of quiet, red, pink and white noises respectively. After a laboratory experiment, details of psychomotor speed, continuous performance, executive function and working memory were recorded.

Results: Red, pink and white noises were significantly positive in comparison with the quiet environment of the psychomotor speed test. As for the continuous performance test, pink noise gave the only significantly positive result. Red, pink and white noise resulted in a better executive function test. Red and pink noise showed significantly positive improvement, while white noise was significantly positive in comparison with the quiet environment of the working memory test. In addition, the results from the comfort questionnaires showed that red and pink noise increase the possibility of better judgment, implementation, and overall environment.

Conclusion: At present time, it is considered that noise has negative effects on hearing and health. However, experimental results show that certain noise can enhance environmental comfort. It is feasible, in the future, to use knowledge of colour noises to improve productivity in a workplace with a healthy environment.