Engineering Controls Database
Printing and Cutting Press – Noise Case Study
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Overview: The case history presented here is one of sixty-one case histories that were published by the National Institute for Occupational Safety and Health (NIOSH) in 1978 as part of an industrial noise control manual [NIOSH 1979]. The case histories are examples of engineering tasks that have been completed not only by professional noise control engineers but also by non-acoustical specialists who used common sense to solve their noise problems. The case histories were chosen primarily because the amount of noise reduction actually achieved was measured. Such engineering results, even if not directly applicable to a specific situation, illustrate general principles that may point the way to a successful result. They are intended to be useful to production and safety engineers, health personnel, and other factory personnel who are not specialists in noise control. Case study: In the manufacture of folding cartons, one method is to print the cartons in a web, using multiple gravure color stations and feeding the printed web into a reciprocation cutting press. The reciprocation cutting press, using a rule die, cuts the cartons and delivers cut cartons to a delivery belt. The rotary printing operation was not noisy, but the cutting press noise from the cutting head was in the range of 93 to 95 dBA at the normal operator position. The take-off operators were far enough from the noise source so that noise at their station was below 90 dBA. |
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| A sound level of 95 dBA only allows for 47 minutes of safe, unprotected exposure according to NIOSH guidelines.Hearing loss is one of the most common occupational diseases in America today and the second most self-reported occupational illness or injury. Approximately 30 million workers are exposed to hazardous noise on the job and there are approximately 16 million Americans with noise-induced hearing loss. | |
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The goal is to lower this level to a safe range where a worker can be safely exposed an entire work shift. Figure 1 shows the operator location, control station, cutting head, and carton delivery. To reduce the noise of the cutter head at the operator position, a barrier wall was used. As access to the unit for job changes and maintenance was important, the barrier wall was specified to be lead-loaded vinyl sound stopper curtain material, available on a made-to-order basis and designed to be portable. The curtain unit ordered was 7 ft high and 8 ft long, with a 10- x 20-in, viewing port.  |
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| NIOSH [1979]. Industrial noise control manual – revised edition. Cincinnati, OH: U.S. Department of Health Education and Welfare, Public Health Service, Center for Disease Control, National Institute for Occupational Safety and Health, DHEW (NIOSH) Publication No. 79-117. | |
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cutting press cutting press noise noise noise control noise control printing printing |
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The noise at the operator control console was reduced from the 93- to 95-dBA range to an 86- to 87-dBA range. The operator performed inspection and adjustment at the cutter head for a few hours daily, as required, but was still within the time exposure limits. Comments: To get any attenuation from barrier walls, the receiver must be located with respect to the noise source so as to be beyond 30 degrees into the acoustical shadow line, as a rule-of-thumb. Note that in the top view, Figure 13.24, the pressman is just within this line. In Figure 2, showing over-the-wall vertical plane limitations of this same rule-of-thumb, the pressman is well within this limiting area. The curtain met the objective, since only a small attenuation of about 5 to 6 dB was required and the actual real attenuation was 7 to 8 dB. More attenuation would require a larger curtain. [img=2] |