Table 2.
Distribution of noise exposure levels monitoring posts among the industry in different stratification - Beijing, 2023.
| Stratification variables | Number of samples, n | Noise exposure level LEx,8h/LEx,40h* [dB(A)] | ||
|---|---|---|---|---|
| M (Q1, Q3) | Min, Max | The proportion of noise exposure levels ≥85 dB(A) (n, %) | ||
| Districts | ||||
| District A | 3 | 72.3 (70.0, 72.4) | 70.0, 72.4 | 0 (0) |
| District B | 9 | 74.2 (70.0, 77.5) | 70.0, 79.9 | 0 (0) |
| District C | 42 | 81.2 (78.6, 84.5) | 71.1, 91.9 | 6 (14.29) |
| District D | 22 | 80.2 (76.3, 81.3) | 71.7, 103.9 | 2 (9.09) |
| District E | 10 | 74.5 (70.3, 77.4) | 70.3, 88.3 | 1 (10.00) |
| District F | 15 | 78.6 (76.2, 86.4) | 70.7, 90.7 | 4 (26.67) |
| District G | 10 | 73.6 (71.0, 80.5) | 70.3, 84.6 | 0 (0) |
| District H | 198 | 80.7 (77.2, 83.5) | 70.0, 97.8 | 35 (17.68) |
| District I | 193 | 80.1 (76.8, 84.2) | 70.0, 101.7 | 46 (23.83) |
| District J | 367 | 82.5 (78.0, 85.9) | 70.0, 105.1 | 117 (31.88) |
| District K | 253 | 82.3 (78.9, 87.7) | 70.4, 100.8 | 86 (33.99) |
| District L | 175 | 81.1 (77.5, 84.1) | 70.0, 101.1 | 33 (18.86) |
| District M | 182 | 81.2 (78.3, 83.0) | 70.70 89.6 | 2 (1.10) |
| District N | 99 | 80.2 (74.8, 83.3) | 70.0, 94.9 | 16 (16.16) |
| District O | 83 | 81.8 (79.7, 84.7) | 72.1, 100.7 | 19 (22.89) |
| District P | 29 | 79.4 (76.2, 81.9) | 71.0, 88.8 | 3 (10.34) |
| Statistic | H = 98.1407, p < 0.0001 | P < 0.0001 | ||
| Industries | ||||
| Electricity and heat production and supply industry | 20 | 82.9 (79.3, 84.8) | 77.1, 87.1 | 4 (20.00) |
| Manufacturing of other nonmetallic mineral products | 134 | 80.7 (77.2, 83.8) | 70.4, 100.6 | 26 (19.40) |
| Ferrous metal smelting and rolling industry | 10 | 83.4 (80.6, 87.5) | 73.2, 105.1 | 3 (30.00) |
| Manufacturing of chemicals and chemical products | 31 | 76.2 (71.0, 79.5) | 70.0, 87.6 | 2 (6.45) |
| Computer, communications and other electronic equipment manufacturing | 67 | 79.7 (73.0, 82.6) | 70.0, 101.1 | 9 (13.43) |
| Manufacturing of furniture | 21 | 85.3 (80.6, 86.4) | 71.9, 95.7 | 11 (52.38) |
| Manufacturing of metal products | 292 | 81.5 (77.1, 85.7) | 70.0, 97.8 | 81 (27.74) |
| Manufacturing of motor vehicles | 318 | 82.0 (79.2, 85.0) | 70.5, 95.7 | 79 (24.84) |
| Manufacturing of coke and refined petroleum products | 3 | 79.3 (78.0, 82.7) | 78.0, 82.7 | 0 (0.00) |
| Railway, shipping, aerospace and other transportation equipment manufacturing | 92 | 83.5 (79.0, 87.8) | 71.7, 103.9 | 35 (38.04) |
| General equipment manufacturing | 188 | 80.1 (75.4, 83.9) | 70.0, 101.7 | 40 (21.28) |
| Pharmaceutical manufacturing industry | 6 | 83.4 (82.1, 84.3) | 79.2, 84.6 | 0 (0.00) |
| Instrumentation manufacturing industry | 16 | 81.0 (74.8, 87.2) | 70.8, 100.8 | 4 (25.00) |
| Printing and reproduction of recorded media industry | 259 | 81.2 (77.9, 83.1) | 70.0, 93.7 | 26 (10.04) |
| Nonferrous metal smelting and rolling industry | 25 | 81.6 (80.7, 83.6) | 71.9, 95.2 | 3 (12.00) |
| Special equipment manufacturing industry | 208 | 80.4 (76.7, 83.9) | 70.0, 96.6 | 47 (22.60) |
| Statistic | H = 89.4629, P < 0.0001 | P < 0.0001 | ||
| Enterprise-scale | ||||
| Large and medium enterprises | 380 | 81.4 (78.0, 85.9) | 70.1, 105.1 | 105 (27.63) |
| Small and micro-sized enterprises | 1,310 | 81.1 (77.5, 84.1) | 70.0, 101.7 | 265 (20.23) |
| Statistic | H = 6.1861, p = 0.0129 | F = 0.9990, p = 0.0030 | ||
| Ownership type | ||||
| State-owned | 204 | 81.4 (77.2, 84.7) | 70.0, 103.9 | 47 (23.04) |
| Collective | 39 | 80.4 (76.6, 82.7) | 70.0, 93.7 | 2 (5.13) |
| Joint-equity cooperative enterprises | 10 | 80.5 (77.2, 81.5) | 70.0, 81.5 | 0 (0.00) |
| Joint-operate | 10 | 79.4 (72.4, 82.9) | 71.7, 87.1 | 2 (20.00) |
| Private | 86 | 78.6 (76.0, 82.2) | 70.0, 94.9 | 11 (12.79) |
| Incorporated company | 27 | 80.6 (75.9, 87.9) | 70.8, 100.8 | 8 (29.63) |
| Limited liability company | 1,023 | 81.2 (77.9, 84.5) | 70.0, 105.1 | 226 (22.09) |
| Hong Kong, Macau, and Taiwan invested enterprises | 7 | 84.1 (80.9, 89.5) | 79.4, 94.9 | 3 (42.86) |
| Foreign | 214 | 81.5(78.2, 85.1) | 70.3, 101.7 | 54 (25.23) |
| Others | 70 | 80.7 (77.2, 85.0) | 70.0, 101.1 | 17 (24.29) |
| Statistic | H = 26.4413, p = 0.0017 | p = 0.0170 | ||
| Total | 1,690 | 81.1 (77.6, 84.4) | 70.0, 105.1 | 370 (21.89) |
*LEx,8h: Normalization of equivalent continuous A-weighted sound pressure level to a nominal 8 h working day. LEx,40h: Normalization of equivalent continuous A-weighted sound pressure level to a nominal 40 h working week.