TABLE 5.
The kurtosis distribution information of some work types in the manufacturing industry [n: the number of workers investigated in the kurtosis analysis in the corresponding work type; correction value = 6.5*log10(β/3), where the β is the mean of the kurtosis values of all the workers in that work type]
| Industry | Work Type | Kurtosis (β) | Correction (dB) | Unadjusted LAeq.8h (dBA) | |
|---|---|---|---|---|---|
| Mean±SD (Min–Max) | Mean±SD (Min–Max) | n | |||
| K1 (3 ≤ βN ≤ 10) | |||||
| Textile mill | Spinning | 3.3 ± 2.1 (3.0–9.4) | 0.3 | 98.7 ± 2.3 (93.8–102.0) | 109 |
| Weaving | 4.1 ± 3.0 (3.1–11.7) | 0.9 | 92.4 ± 2.4 (85.9–95.6) | 49 | |
| Knitter | 5.2 ± 2.2 (3.3–17.5) | 1.6 | 97.5 ± 1.8 (93.3–104.9) | 84 | |
| Mechanist | 8.6 ± 4.6 (4.0–17.8) | 3.0 | 93.5 ± 5.0 (84.9–98.4) | 14 | |
| Spandex | Winding | 9.7 ± 4.4 (3.2–23.7) | 3.3 | 95.8 ± 4.7 (82.3–104) | 52 |
| Papermill | Defibrinating | 6.6 ± 2.8 (4.3–8.4) | 2.2 | 87.1 ± 2.2 (84.5–90.4) | 7 |
| Pulping | 9.0 ± 3.8 (3.0–15.4) | 3.1 | 89.0 ± 4.1 (82.2–96.9) | 28 | |
| Rewinder | 8.6 ± 2.3 (3.5–12) | 3.0 | 88.3 ± 2.5 (84.9–92.5) | 11 | |
| K2 (10 < βN ≤50) | |||||
| Auto brake pad manufactory | Assemblyman | 36.3 ± 16.1 (9.6–72.8) | 7.0 | 85.6 ± 5.2 (71.7–96.7) | 57 |
| Machining | 32.6 ± 28.1 (8.6–141.9) | 6.7 | 89.0 ± 5.2 (77.4–103.8) | 100 | |
| Auto parts manufactory | Thread rolling | 11.2 ± 4.9 (3.9–25.3) | 3.7 | 89.5 ± 2.8 (82.5–94.6) | 41 |
| Depositing | 13.7 ± 7.1 (5.0–32.1) | 4.3 | 88.8 ± 3.0 (83.0–97.7) | 19 | |
| Tapping | 15.2 ± 7.0 (6.8–27.9) | 4.6 | 90.1 ± 1.7 (86.5–92.9) | 14 | |
| Numerical control machine | 15.5 ± 9.4 (7.8–32.0) | 4.6 | 87.0 ± 5.5 (79.3–93.1) | 6 | |
| Spot welding | 16.1 ± 5.0 (6.6–22.5) | 4.7 | 90.2 ± 2.0 (87–93.5) | 11 | |
| Lathe worker | 16.6 ± 13.7 (4.1–63.3) | 4.8 | 85.9 ± 4.3 (72.8–92.4) | 21 | |
| Drawing wire | 17.4 ± 8.4 (7.0–32.5) | 5.0 | 88.9 ± 4.1 (82.9–98.0) | 16 | |
| Packing | 21.2 ± 10.5 (6.4–43.2) | 5.5 | 85.2 ± 4.7 (73.6–91.0) | 33 | |
| Sorting | 22.2 ± 14.8 (4.2–81.3) | 5.6 | 87.0 ± 3.7 (78.7–93.6) | 38 | |
| Automotive fasteners | Electroplating | 17.3 ± 12.7 (4.1–63.4) | 4.9 | 89.9 ± 6.4 (76–103.8) | 31 |
| Cold heading | 25.2 ± 16.9 (4.7–79.7) | 6.0 | 90.4 ± 5.2 (80.9–104.7) | 60 | |
| Polishing | 25.7 ± 16 (4.8–54.8) | 6.1 | 92.1 ± 6.4 (80.7–100.3) | 10 | |
| Heat treatment | 27.3 ± 18.7 (6.5–78) | 6.2 | 89.9 ± 4.1 (82.5–99.9) | 31 | |
| Automatic lathe work | 29.6 ± 17 (6.3–67.6) | 6.5 | 89.2 ± 4.8 (81.5–96.7) | 16 | |
| Baby carriage manufactory | Punch | 15.6 ± 5.4 (7.5–29.0) | 4.6 | 93.9 ± 3.2 (87.6–98.6) | 42 |
| Stamping | 28.4 ± 18.4 (7.8–85.9) | 6.3 | 91.7 ± 8.2 (73.5–105.4) | 85 | |
| Commercial vehicle body factory | Craneman | 24.0 ± 20.2 (3.5–88.7) | 5.9 | 90.6 ± 6.0 (78.6–104.3) | 25 |
| Spot welding | 26.6 ± 21.6 (5–104.4) | 6.2 | 89.8 ± 3.3 (83.7–97.8) | 23 | |
| Electric welder | 40.0 ± 29.4 (3.4–187.1) | 7.3 | 91.5 ± 7.4 (77.3–104.1) | 79 | |
| Electrical appliance factory | Stretching | 26.3 ± 9.7 (15.8–47.7) | 6.1 | 87.6 ± 3.1 (82.9–95.6) | 12 |
| Sanding | 26.9 ± 20.1 (6.1–76.8) | 6.2 | 87.1 ± 5.0 (75.8–94.6) | 9 | |
| Electrical appliance factory | Forming | 27.8 ± 12.6 (12.9–50.4) | 6.3 | 79.8 ± 3.8 (75.3–88.0) | 8 |
| Assemblyman | 50.0 ± 27.7 (19.7–91.8) | 7.9 | 76.4 ± 2.5 (73.0–80.1) | 18 | |
| Final assembly plant for automobiles | Machining | 19.7 ± 8.9 (8.1–34.6) | 5.3 | 88.8 ± 4.7 (82.7–98.6) | 9 |
| Assemblyman | 28.0 ± 25.2 (3.4–196.2) | 6.3 | 90.9 ± 5.0 (79.8–105.6) | 221 | |
| Hardware factory | Sand blast | 11.4 ± 2.9 (8.1–15.8) | 3.8 | 90.1 ± 2.1 (87.5–93.5) | 8 |
| Stamping | 20.2 ± 11.0 (7.1–48.5) | 5.4 | 87.5 ± 4.2 (76–93.5) | 20 | |
| Benchwork | 33.2 ± 24.3 (10.0–92.4) | 6.8 | 83.2 ± 5.3 (75–92.7) | 11 | |
| Heavy truck engine factory | Casting | 21.2 ± 16.1 (8–55.7) | 5.5 | 89.7 ± 9.0 (81.9–113) | 10 |
| Hydroelectric | Drilling | 21.3 ± 10.6 (7.2–39.1) | 5.5 | 90.2 ± 5.5 (81.5–99.7) | 15 |
| Cold operating | 42.4 ± 18.9 (13.4–78.4) | 7.5 | 95.6 ± 3.6 (90.3–100.3) | 8 | |
| Modeling | 42.8 ± 18.1 (12.0–75.3) | 7.5 | 88.9 ± 6.2 (73.5–94.6) | 10 | |
| Iron and steel plant | Steel rolling | 14.4 ± 9.1 (4.6–58.9) | 4.4 | 90.5 ± 5.3 (76.9–96.7) | 41 |
| Finishing | 16.8 ± 8.2 (6.1–42.4) | 4.9 | 88.4 ± 4.3 (74.2–99.8) | 21 | |
| Loading | 22.4 ± 4.1 (13.3–25.1) | 5.7 | 86.7 ± 2.9 (83.3–90.6) | 8 | |
| Machinery | Grinding | 26.2 ± 10.4 (16.1–58.7) | 6.1 | 84.6 ± 6.4 (72.6–93.8) | 13 |
| Metal processing | 47.6 ± 19.6 (26.2–80.5) | 7.8 | 82.2 ± 2.3 (79.0–85.4) | 7 | |
| Machinery and electric | Assemblyman | 37.8 ± 28.6 (7.8–240.7) | 7.1 | 86.2 ± 3.2 (77.7–98.0) | 147 |
| K3 (βN > 50) | |||||
| Electrical appliance | Wiring | 53.7 ± 41.7 (16.2–156.6) | 8.1 | 75.6 ± 2.3 (71.2–79.2) | 10 |
| Furniture manufactory | Frame nailing | 81.7 ± 44.3 (24.9–158.5) | 9.3 | 89.5 ± 5.4 (76.3–100.5) | 51 |
| Woodworking | 119.2 ± 71.6 (21.3–306.8) | 10.4 | 88.5 ± 3.6 (81.9–95.4) | 23 | |
| Assemblyman | 102.4 ± 69.6 (42.2–250) | 10.0 | 89.2 ± 4.3 (83.9–96.9) | 12 | |
| Nail gunning | 246.5 ± 172.2 (31.5–925.5) | 12.4 | 89.0 ± 4.4 (76.7–98.8) | 213 | |
| Grid structure | Assemblyman | 103.0 ± 69.7 (34.3–315.6) | 10.0 | 93.8 ± 3.5 (87.3–101) | 26 |
| Kitchen and bath manufacturing | Assemblyman | 69.7 ± 62.9 (17.4–177.2) | 8.9 | 81.6 ± 2.3 (77.9–85.0) | 13 |