The application of a noise‐rating scale composed of hue‐scale and L_Aeq on various kinds of noise sources for noise map Free

In addition to reporting the results of measurements of existing environmental noise and the results of calculations of noise from projected activities, the application of color for representing in terms of noise zones may be useful (ISO 1996‐2). Between color and noise, in spite of differences, there exists an interaction, although the connection between the visible and the audible expression is subjective. Subjectivity can in a given moment become objective, if one succeeds in unifying the visible and the audible. In the case of colored paper on a white background, the relation between the hue level expressing the psychological effect (annoyance) and L_Aeq(5min) (dB) of typical noise sources was discussed in a laboratory experiment. According to the obtained noise‐rating scale, the seven‐hue scale and L_Aeq(5min) are correlated well (r=0.874) as follows: white (value V9; not at all bothersome) ⇔ below 26 dB, light blue (hue 2.5B, value 8/chrome 4; not bothersome) ⇔ 26 to 37 dB, light green (2.5BG, 7/8; not too bothersome) ⇔ 37 to 49 dB, bright yellow (7.5YR, 7/14; a little annoying) ⇔ 49 to 61 dB, brown (10R, 4/8; annoying) ⇔ 61 to 70 dB, purple (2.5P, 4/10; very annoying) ⇔ 70 to 80 dB and red (5R, 5/14; extremely annoying) ⇔ over 80 dB.