# Acoustic Environment and Noise Exposure in Fitness Halls
## 3 Results and Discussion
### Noise Levels and Noise Exposure
The results of activity noise levels, L\({}_{\text{A,eq}}\), over 50 min during the workout sessions are shown in Table 3. In this study, the L\({}_{\text{A,eq}}\) measured during workout lessons is quite variable, reaching values between 80.0 and 110.5 dB(A). This is considered high in comparison with a sample study conducted in Italy [15], which was conducted on 15 gymnasia and 3 swimming pools. They observed that the L\({}_{\text{A,eq}}\) measured for 1 h during different lessons varied between 70.0 and 87.0 dB(A). A study conducted in China [54] demonstrated that the L\({}_{\text{A,eq}}\) of the activity noise varied between 63.0 and 70.0 dB(A). In another study [60], occupational noise exposure from indoor arena hockey games was studied, and the average sound equivalent levels ranged from 81.0 to 97.0 dB(A). The average of activity noise level L\({}_{\text{A,eq}}\) at IS & G halls is 92.6 dB(A). The daily noise dose exposure percentage for the 50 min workout session and daily noise dose exposure percentage for 3 h are listed in Table 3. From the mentioned measurements, the personal daily dose, A-weighting L\({}_{\text{EX, 8 h}}\) in dB(A), was calculated and is presented in the table. Evaluating the data from the field survey, it was found that instructors working in 40% of the studied IS & G halls receive a daily noise dose exceeding 100%. The instructors in IS & G halls are exposed to an average personal daily dose (L\({}_{\text{EX, 8 h}}\)) of 89.8 dB(A), ranging between 80.5 and 107.5 dB(A). Previous studies [15] have shown that 20-25% of instructors could achieve weekly noise exposure higher than 80.0 dB(A). The results from our study are well above these values and show a higher risk of exposure to occupational noise. The results for personal daily dose A-weighting (L\({}_{\text{EX, 8 h}}\)) are shown in Figure 5. Evaluating the personal daily dose, referring to JAC [38], it was found that 90% of measurement results were above the OEL of 85.0 dB(A). Applying the limit action values in the Physical Agents (Noise) Directive (Table 5) [37], about 15% of the studied IS & G halls have a lower exposure action value, 30% have an upper noise exposure action value, and 55% have a noise exposure limit value. In a previous study [15], it was found that a weekly noise exposure(L\({}_{\text{EX, w}}\)) higher than 80.0 dB(A) occurs when the number of users is more than 30, time exposure is 25 h or more per week, and reverberation time is more than 5 s. \begin{table}
\begin{tabular}{c c c} \hline \hline  & **L\({}_{\text{A}EP,d}\)** & **L\({}_{\text{C}peak}\)** \\ \hline Lower exposure action value & 80 dB & 135 dB or 112 Pa \\ \hline Upper exposure action value & 85 dB & 137 dB or 140 Pa \\ \hline Exposure limit value & 87 dB & 140 dB or 200 Pa \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Exposure action and limit values under Physical Agents (Noise) Directive [37]. reverberation time for gymnasium halls in Category II is calculated according to BB [1]. For this category, all of the halls met the recommended \(T_{\textit{mf}}\). This is because the gymnasium' floors are covered with material characterized by a high absorption coefficient, for example, foam or vinyl, or the gymnasium has a low relative height, resulting in moderate volume because these buildings were rehabilitated to be used as gymnasia and were previously used for other purposes. The shorter reverberation times can be attributed to small volume and absorbent room surfaces. Reverberation time contributes to speech intelligibility and reverberation times above 1 s produce a loss in speech discrimination and make speech perception more difficult and strained [61; 62]. The average of measured mid-frequency reverberation time, \(T_{\textit{mf}}\), values (average + standard deviation) for IS & G halls in the three categories compared with recommended \(T_{\textit{mf}}\) is shown in Figure 7.  
Figure 6: Measured mid-frequency reverberation time, \(T_{\textit{mf}}\) (s), for the studied IS & G halls.