Table 5 Predicted speech-hearing-loss percentiles of the averaged air-conduction thresholds at 2, 3, and 4 kHz (PTA₂₃₄), depending on noise exposure (L_EX,8 h) and age.Cells are colour-coded by predicted PTAL₂₃₄ severity band: green = ≤20 dB HL (within normal limits), yellow = 21- 34 dB HL (mild hearing loss), red = 35-49 dB HL (moderate HL), and purple = 50-64 dB HL (moderately severe HL). GK number denotes the number of go-karts operating simultaneously, which determines the corresponding L_EX,8 h exposure shown in the left column.

From: Occupational noise and vibration risks for go-kart instructors in a dynamic track environment