Exposure Characterization for Highway Construction Part I: Cut and Cover and Tunnel Finish Stages

Abstract

The purpose of this study was to characterize respirable dust, crystalline silica, diesel, and noise exposures to construction workers on a large highway construction project in Boston, Massachusetts. The study primarily focused on operating engineers and laborers, and to a lesser extent on ironworkers and carpenters during the tunnel finish and cut and cover stages. Full and partial shift noise dosimeter measurements were collected. Eighty percent of the 40 noise measurements were at or above 85 dBA, with the operating engineers averaging 91 dBA. Sample collection for respirable dust, crystalline silica, and diesel particulates measured as elemental carbon was done using cyclones and personal cascade impactors. Exposure to respirable dust ranged from 0.06 to 21.77 mg/m3 for the 77 workers sampled, with the laborers having the highest mean concentration of 2.85 mg/m3. The respirable quartz measurements for the 32 samples collected ranged from the detection limit of 0.008 mg/m3 to 1.64 mg/m3, with the highest mean concentration of 0.31 mg/m3 attributed to the laborers. The use of drills, when compared to other machine types, produced the highest exposures to respirable quartz. The levels for elemental carbon ranged from 4 to 178 micrograms/m3 (mean of 41 micrograms/m3) inside enclosed work spaces, compared with 0.5 to 53 micrograms/m3 (mean of 10 micrograms/m3) for samples collected in unenclosed work sites. Statistical modeling of the factors influencing the elemental carbon exposures showed that machine type, worker distance from the diesel source, the number of other diesel sources in the work area, and site enclosure were all significant exposure determinants. The results indicate that high exposures to noise, respirable dust, and crystalline silica are common in the highway construction industry.

Lung cancer in heavy equipment operators and truck drivers with diesel exhaust exposure in the construction industry

“…A study of US highway construction workers in 1994-95 found a mean concentration of 14 µg/m 3 elemental carbon (range 0.5-53 µg/m 3 , n = 14) in operating engineers working outdoors, mainly handling cranes, lifters, and earth movers. 17 The exposure was considerably higher for operating engineers during work in tunnels (mean 39 µg/m 3 ). The background concentration on the work site was fairly low (mean 3 and 6 µg/m 3 at two places, range 0.5-7).…”

Airborne Silica Dust; Trial Monitoring in a Drill and Blast Tunnel in Hong Kong and Comparison with Measurements in Other Tunnels and in General Construction Elsewhere

“…Two papers concerned with the cut and cover and Immersed Tube tunnels for the Boston Central Artery/Tunnel Project [8,9] are the only ones that the authors have discovered which report results for (6-hour) personal sampling for percussive concrete drilling (8-hour workdays), (Table 6). This is surprising, given its wide-spread use by civil engineering, building and building service contractors.…”

Noise Exposure of Workers and the Use of Hearing Protection Equipment in New Zealand

“…In construction, Edelson et al 17 measured mean L Aeq levels for workers in the USA to be 89.8 dB. Other studies have shown that many trades within construction have the potential to be exposed to noise levels above 85 dB, [17][18][19][20][21][22] even those trades that may be expected to be low noise, such as electricians. 23 In agriculture, previous studies have documented high noise levels, frequently above 85 dB.…”