Background
This is the second update of a Cochrane Review originally published in 2009. Millions of workers worldwide are exposed to noise levels that increase their risk of hearing disorders. There is uncertainty about the effectiveness of hearing loss prevention interventions.

Objectives
To assess the effectiveness of non-pharmaceutical interventions for preventing occupational noise exposure or occupational hearing loss compared to no intervention or alternative interventions.

Search methods
We searched the CENTRAL; PubMed; Embase; CINAHL; Web of Science; BIOSIS Previews; Cambridge Scientific Abstracts; and OSH UPDATE to 3 October 2016.

Selection criteria
We included randomised controlled trials (RCT), controlled before-after studies (CBA) and interrupted time-series (ITS) of non-clinical interventions under field conditions among workers to prevent or reduce noise exposure and hearing loss. We also collected uncontrolled case studies of engineering controls about the effect on noise exposure.

Data collection and analysis
Two authors independently assessed study eligibility and risk of bias and extracted data. We categorised interventions as engineering controls, administrative controls, personal hearing protection devices, and hearing surveillance.

Main results
We included 29 studies. One study evaluated legislation to reduce noise exposure in a 12-year time-series analysis but there were no controlled studies on engineering controls for noise exposure. Eleven studies with 3725 participants evaluated effects of personal hearing protection devices and 17 studies with 84,028 participants evaluated effects of hearing loss prevention programmes (HLPPs).

Effects on noise exposure

Engineering interventions following legislation

One ITS study found that new legislation in the mining industry reduced the median personal noise exposure dose in underground coal mining by 27.7 percentage points (95% confidence interval (CI) -36.1 to -19.3 percentage points) immediately after the implementation of stricter legislation. This roughly translates to a 4.5 dB(A) decrease in noise level. The intervention was associated with a favourable but statistically non-significant downward trend in time of the noise dose of -2.1 percentage points per year (95% CI -4.9 to 0.7, 4 year follow-up, very low-quality evidence).

Engineering intervention case studies

We found 12 studies that described 107 uncontrolled case studies of immediate reductions in noise levels of machinery ranging from 11.1 to 19.7 dB(A) as a result of purchasing new equipment, segregating noise sources or installing panels or curtains around sources. However, the studies lacked long-term follow-up and dose measurements of workers, and we did not use these studies for our conclusions.

Hearing protection devices

In general hearing protection devices reduced noise exposure on average by about 20 dB(A) in one RCT and three CBAs (57 participants, low-quality evidence). Two RCTs showed that, with instructions for insertion, the attenuation of noise by earplugs was 8.59 dB better (95% CI 6.92 dB to 10.25 dB) compared to no instruction (2 RCTs, 140 participants, moderate-quality evidence).

Administrative controls: information and noise exposure feedback

On-site training sessions did not have an effect on personal noise-exposure levels compared to information only in one cluster-RCT after four months' follow-up (mean difference (MD) 0.14 dB; 95% CI -2.66 to 2.38). Another arm of the same study found that personal noise exposure information had no effect on noise levels (MD 0.30 dB(A), 95% CI -2.31 to 2.91) compared to no such information (176 participants, low-quality evidence).

Effects on hearing loss

Hearing protection devices

In two studies the authors compared the effect of different devices on temporary threshold shifts at short-term follow-up but reported insufficient data for analysis. In two CBA studies the authors found no difference in hearing loss from noise exposure above 89 dB(A) between muffs and earplugs at long-term follow-up (OR 0.8, 95% CI 0.63 to 1.03 ), very low-quality evidence). Authors of another CBA study found that wearing hearing protection more often resulted in less hearing loss at very long-term follow-up (very low-quality evidence).

Combination of interventions: hearing loss prevention programmes

One cluster-RCT found no difference in hearing loss at three- or 16-year follow-up between an intensive HLPP for agricultural students and audiometry only. One CBA study found no reduction of the rate of hearing loss (MD -0.82 dB per year (95% CI -1.86 to 0.22) for a HLPP that provided regular personal noise exposure information compared to a programme without this information.

There was very-low-quality evidence in four very long-term studies, that better use of hearing protection devices as part of a HLPP decreased the risk of hearing loss compared to less well used hearing protection in HLPPs (OR 0.40, 95% CI 0.23 to 0.69). Other aspects of the HLPP such as training and education of workers or engineering controls did not show a similar effect.

In three long-term CBA studies, workers in a HLPP had a statistically non-significant 1.8 dB (95% CI -0.6 to 4.2) greater hearing loss at 4 kHz than non-exposed workers and the confidence interval includes the 4.2 dB which is the level of hearing loss resulting from 5 years of exposure to 85 dB(A). In addition, of three other CBA studies that could not be included in the meta-analysis, two showed an increased risk of hearing loss in spite of the protection of a HLPP compared to non-exposed workers and one CBA did not.

Authors' conclusions
There is very low-quality evidence that implementation of stricter legislation can reduce noise levels in workplaces. Controlled studies of other engineering control interventions in the field have not been conducted. There is moderate-quality evidence that training of proper insertion of earplugs significantly reduces noise exposure at short-term follow-up but long-term follow-up is still needed.

There is very low-quality evidence that the better use of hearing protection devices as part of HLPPs reduces the risk of hearing loss, whereas for other programme components of HLPPs we did not find such an effect. The absence of conclusive evidence should not be interpreted as evidence of lack of effectiveness. Rather, it means that further research is very likely to have an important impact.

Interventions to prevent occupational noise-induced hearing loss.

The former Homestakegold mine in Lead, South Dakota has been transformed into a dedicated facility to pursue underground research in rare-process physics, as well as offering research opportunities in other disciplines such as biology, geology and engineering. A key component of the Sanford Underground Research Facility (SURF) is the Davis Campus, which is in operation at the 4850-foot level (4300 m.w.e.) and currently hosts two main physics projects: the LUX dark matter experiment and the MAJORANA DEMONSTRATOR neutrinolessdouble-beta decay experiment. In addition, two low-background counters currently operate at the Davis Campus in support of current and future experiments. Expansion of the underground laboratory space is underway at the 4850L Ross Campus in order to maintain and enhance low- background assay capabilities as well as to host a unique nuclear astrophysics accelerator facility. Plans to accommodate other future experiments at SURF are also underway and include the next generation of direct-search dark matter experiments and the Fermilab-led international long- baseline neutrino program. Planning to understand the infrastructure developments necessary to accommodate these future projects is well advanced and in some cases have already started. SURF is a dedicated research facility with significant expansion capability.

http://iopscience.iop.org/article/10.1088/1742-6596/606/1/012015/pdf

The Sanford Underground Research Facility at Homestake

s .................................................................................................................................... 77 Control Technology Reports................................................................................................... 89 Fire Fighter Fatality Investigation and Prevention Reports ................................................ 93 Health Hazard Evaluation Reports ........................................................................................ 97 Author Index ............................................................................................................................. 103 National Occupational Research Agenda (NORA) Index .................................................. 127 NIOSH Bibliography of Communication and Research Products 2013 | v The National Institute for Occupational Safety and Health (NIOSH) plays a vital role in protecting the safety and health of more than 155 million workers in the United States.1 Occupational safety and health experts across the U.S. and worldwide rely on NIOSH research. Researchers at NIOSH contributed to 724 publications in 2013—each furthering the understanding of occupational safety and health. This word cloud was generated from the titles of publications in the NIOSH Bibliography of Communication and Research Products 2013. Larger type indicates the words were used most often in publication titles. Smaller type shows words used less frequently. Source: NIOSHTIC-2 Bibliographic Database, www.wordle.net. U.S. Department of Labor, Bureau of Labor Statistics [2013]. Current Population Survey. 2012. Introduction NIOSH Bibliography of Communication and Research Products 2013 | vii

/pdf/niosh-bibliography-of-communication-and-research-products-f9fnhhp6sy.pdf

NIOSH bibliography of communication and research products 2017

In one embodiment, a coupler system for coupling a top drive and a tool, including a drive member of the top drive configured to transfer torque. The drive member having a housing with a bore therethrough and a window formed substantially laterally through the housing. An adapter of the tool is configured to be inserted through the window of the housing. In another embodiment, a method for coupling a top drive to a tool includes moving, the tool adjacent to the top drive, the tool including an adapter and the top drive including a housing having a window formed therethrough. The method also includes aligning the adapter with the window and inserting the adapter substantially laterally into the window of the housing, thereby longitudinally and torsionally coupling the top drive and the tool.

Combined multi-coupler for top drive

The former Homestake gold mine in Lead, South Dakota is being transformed into a dedicated laboratory to pursue underground research in rare-process physics, as well as offering research opportunities in other disciplines such as biology, geology and engineering. A key component of the Sanford Underground Research Facility (SURF) is the Davis Campus, which is in operation at the 4850-foot level (4300 m.w.e) and currently hosts three projects: the LUX dark matter experiment, the MAJORANA DEMONSTRATOR neutrinoless double-beta decay experiment and the CUBED low-background counter. Plans for possible future experiments at SURF are well underway and include long baseline neutrino oscillation experiments, future dark matter experiments as well as nuclear astrophysics accelerators. Facility upgrades to accommodate some of these future projects have already started. SURF is a dedicated facility with significant expansion capability.

/pdf/the-sanford-underground-research-facility-at-homestake-3tlr6z1vyx.pdf

Since 2009, the Mine Safety and Health Administration (MSHA) has required mines to install refuge alternatives (RAs) in underground coal mines. One of the biggest concerns with occupied RAs is the possible severity of the resulting thermal environment. In 30 CFR 7.504, the maximum allowable apparent temperature (AT) for an occupied RA is specified as 35 °C (95 °F). Manufacturers must conduct heat/humidity tests to demonstrate that their RAs meet the 35 °C (95 °F) AT limit. For these tests, heat input devices are used to input the metabolic heat of actual miners. A wide variety of test methods, sensors, and heat input devices could be used when conducting such tests. Since 2012, the National Institute for Occupational Safety and Health (NIOSH) has conducted over thirty 96-hour heat/humidity tests on four different RAs. This paper discusses the test equipment and procedures used during these investigations. This information is useful for RA manufacturers conducting RA heat/humidity tests, for other researchers investigating RA heat/humidity buildup, and for those who need to assess the thermal environment of any confined space where people may be trapped or are seeking refuge.

A test method for evaluating the thermal environment of underground coal mine refuge alternatives

Workers in coal-preparation plants, where vibrating screens are significant noise sources, are often exposed to sound levels exceeding 90 dB(A) The National Institute for Occupational Safety and Health, a major coal company and a vibrating-screen manufacturer conducted a cooperative study of vibrating-screen noise Rubber isolators reduced sound levels by 1 dB Urethane screen panels did not reduce sound levels in this case Drive noise was determined to be the dominant noise source on the screen Damped side plates reduced vibration levels on the screen sides by 1 to 7 dB(A) Detailed results of the study are presented

/pdf/noise-and-vibration-reduction-of-a-vibrating-screen-3j55tjnl9x.pdf

Noise And Vibration Reduction Of A Vibrating Screen

Hearing loss was the second-most common illness reported to the Mine Safety and Health Administration (MSHA) in 2009. Furthermore, between 2000 and 2010, 30% of all noise-related injury complaints reported to MSHA were for coal preparation plant employees. Previous National Institute for Occupational Safety and Health (NIOSH) studies have shown that vibrating screens are key noise sources to address in order to reduce coal preparation plant noise. In response, NIOSH researchers have developed a suite of noise controls for vibrating screens consisting of constrained layer damping (CLD) treatments, a tuned mechanism suspension, an acoustic enclosure, and spring inserts. Laboratory testing demonstrates that this noise control suite reduces the A-weighted sound power level of the vibrating screen by 6 dB. To provide a comparison to laboratory results and prove durability, field testing of two noise controls was performed on a vibrating screen in a working coal preparation plant. The spring inserts and CLD treatments were selected due to their ease of installation and practicability. Field testing of these controls yielded reductions that were comparable to laboratory results.

/pdf/a-noise-control-package-for-vibrating-screens-cly7n09vlq.pdf

A noise control package for vibrating screens.

A-weighted sound levels around vibrating screens in coal preparation plants often exceed 90 dB(A). The National Institute for Occupational Safety and Health (NIOSH) is actively developing noise controls to reduce noise generated by horizontal vibrating screens. A 121-microphone, 3.5-meter-diameter array was used to perform beamforming to determine locations of significant noise radiation on the screen. Below about 1 kHz, the screen body was found to be the most significant noise source. The beamforming contour maps showed several key locations on the sides of the screen and the feedbox are the most significant contributors. Operating deflection shape (ODS) analysis was used to examine the screen behavior under actual operating conditions. This information is helpful in determining how to modify the screen body to reduce the noise radiated by the screen below 1 kHz. The analysis showed modal vibration patterns on the sides and feed box were the main contributors to noise. The results show several areas on the screen sides and feedbox that can be modified to reduce noise.

/pdf/structural-vibration-as-a-noise-source-on-vibrating-screens-3y2s1k9kow.pdf

Structural Vibration as a Noise Source on Vibrating Screens

Federal regulations require the installation of refuge alternatives (RAs) in underground coal mines. Mobile RAs have a limited ability to dissipate heat, and heat buildup can lead to a life-threatening condition as the RA internal air temperature and relative humidity increase. The U.S. National Institute for Occupational Safety and Health (NIOSH) performed heat testing on a 10-person tent-type training RA and contracted ThermoAnalytics Inc. to develop a validated thermal simulation model of the tested RA. The model was used to examine the effects of the constant mine strata temperature assumption, initial mine air temperature, initial mine strata surface temperature (MSST), initial mine strata temperature at depth (MSTD) and mine strata thermal behavior on RA internal air temperature using 117 W (400 Btu/h) of sensible heat input per simulated miner. For the studied RA, when the mine strata temperature was treated as a constant, the final predicted RA internal air temperature was 7.1°C (12.8°F) lower than it was when the mine strata thermal behavior was included in the model. A 5.6°C (10.0°F) increase in the initial MSST resulted in a 3.9°C (7.1°F) increase in the final RA internal air temperature, whereas a 5.6°C (10°F) increase in the initial MSTD yielded a 1.4°C (2.5°F) increase in the final RA internal air temperature. The results indicate that mine strata temperature increases and mine strata initial temperatures must be accounted for in the physical testing or thermal simulations of RAs.

/pdf/effects-of-mine-strata-thermal-behavior-and-mine-initial-1wc04f4s78.pdf

David S. Yantek

Papers

A test method for evaluating the thermal environment of underground coal mine refuge alternatives

Noise And Vibration Reduction Of A Vibrating Screen

A noise control package for vibrating screens.

Structural Vibration as a Noise Source on Vibrating Screens

Effects of mine strata thermal behavior and mine initial temperatures on mobile refuge alternative temperature.