减低工业噪音的实用指引

1、减低工业噪音的实用指南A Practical Guide toIndustrial Noise Reduction劳工处职业平安及健康部Occupational Safety and Health BranchLabour Department职业平安健康局Occupational Safety and Health Council.本指南由劳工处职业平安及健康部印制This guidebook is prepared by the Occupational Safety and Health Branch2004年10月版 This edition October 2004本指南可在劳工处职

2、业平安及健康部各办事处免费索取，亦可于劳工处网站 :/ .hk/public/os/dD/Noisered.pdf直接下载。有关各办事处的地址及查询 ，请致电25592297.欢迎复印本指南，但作广告、批核或商业用途除外。如需复印，请注明录自劳工处刊物?减低工业噪音的使用指南?。This guidebook is issued free of charge and can be obtained from offices of the Occupational Safety and Health Branch, Labour Department. It can also

3、be downloaded from :/ .hk/eng/public/os/D/Noisered.pdf. For enquiries about addresses and telephone numbers of the offices, please call 2559 2297.This guidebook may be freely reproduced except for advertising, endorsement or commercial purposes. Please acknowledge the source as A Practical

4、 Guide to Industrial Noise Reduction''.published by the Labour Department.减低工业噪音的实用指南A Practical Guide toIndustrial Noise Reduction目录1. 引言 42. 一般的工业噪音问题及解决方法1. 抽气扇噪音 62. 通风喉噪音 63. 喉管噪音 64. 机器噪音 83. 一般嘈吵机器的噪音控制措施 104. 数据查询 12附图 14CONTENTSI. INTRODUCTION 5II. COMMON INDUSTRIAL NOISE PROBLEMS A

5、ND SOLUTION1. FAN NOISE 72. DUCT NOISE 73. PIPE NOISE 74. MACHINERY NOISE 9III. NOISE CONTROL MEASURES FOR COMMON NOISY MACHINES 11IV. USEFUL INFORMATION 13FIGURES 14引言 如雇员处身于公厂及工业经营工作噪音规例规定的初级或顶级措施声级或超越该等声级，东主除提供认可的听觉保护器外，还需尽可能利用其他方法来减低噪音暴露量。为到达这一目标，东主需要实行噪音控制实施方案，这些措施包括考虑到噪音控制技术的开展而定期检讨进一步减低噪音的可行性

6、。限制噪音暴露量的最可靠方法，是减低噪音声级。以下各章列述一般工业噪音来源的简单问题及其可行的解决方法。至于复杂的问题，读者可咨询独立的噪音控制专家或职业平安健康局。INTRODUCTIONWhere employees are exposed at or above the first or peak action levels of the Factories and Industrial Undertakings (Noise at Work) Regulation, the proprietor is required to reduce the noise exposure far

7、as is practicable by means other than provision of approved ear protectors. To achieve this, the proprietor will need to implement a programme of noise control measures which should include regular reviews of the feasibility of further noise reduction, taking account of development in noise control

8、techniques.The most reliable way of limiting exposure is to reduce the noise level itself. The following sections deal with simple problems of common industrial noise sources and their possible solutions. For complicated problems, readers are advised to consult independent noise control specialist o

9、r the Occupational Safety and Health Council.2. 一般工业噪音问题及解决方法1. 抽气扇发出的噪音问题成因解决方法(a) 气流湍动的噪音 由于气流遇上阻碍令空气湍动，因而造成噪音图1防止流动组件产生任何突变防止将抽气扇放置在障碍物、弯位及变形局部的后面图2所有开敞式抽气扇加设锥心或阔钟口形1盖图2将抽气扇放在内衬有吸音物料的箱内图3安装灭声器图3(b) 噑声噪音 由于抽气扇高速运行所产生的噪音减低抽气扇速度另选转速较低的抽气扇(c) 高频率轴承噪音 因轴承损坏而产生噪音更换损坏了的轴承2. 通风喉发出的噪音问题成因解决方法(a) 发出辘辘声噪音的通

10、风喉 由于通风喉外表受气流感应而引致震动图4以承托蹼加强被震动的嵌板的硬度在震动的嵌板使用具阻尼减震材料图5(b) 溢出的低频噪音由于通风喉内的噪音经过通风喉外表图4在通风喉外表加上隔音材料图63. 喉管发出的噪音问题成因解决方法(a) 如钟鸣的喉管噪音因液体在喉管内流动而刺激管壁所引致的震动图7在喉管外表加上隔音材料图8(b) 震动的喉管发出的噪音喉管的震动传送到建筑物其他部份图7用下述物品/方法隔开震动(a) 弹性联轴节图9(b) 在喉管及其承托物之间加设防震器图10II. COMMON INDUSTRIAL NOISE PROBLEMS AND SOLUTIONS1. Fan Noise

11、Causes of ProblemSolutions(a) Turbulent air flow noiseGenerated by turbulence of air due to obstacle in airflow (Fig. 1)-avoid creating any sudden change in flow components-avoid locating fans immediately behind obstacle, bends, transformation sections (Fig. 2)-fit coned or bell mouth cover to open

12、running fans (Fig. 2)-enclose fan in a chamber internally lined with sound absorbing material (Fig. 3)-install silencers (Fig. 3)(b) Whining noiseGenerated by high fan running speed-reduce fan speed-re-select fans of lower rotating speed(c) High frequency bearing noise Generated by worn-out bearing-

13、 replace worn-out bearing2. Duct NoiseCauses of ProblemSolutions(a) Rumbling duct panel noiseCaused by duct surface being induced to vibrate by air flow (Fig. 4)-sitiffen vibrating panel with supporting webs-apply damping material to the vibrating panel (Fig. 5)(b) Low frequency breakout noiseCaused

14、 by noise inside duct passing through duct surface (Fig. 4)-apply lagging to duct surface (Fig. 6)4. Pipe NoiseCauses of ProblemSolutions(a) Ringing pipe noiseCaused by pipe wall being set into vibration by fluid flow inside the pipe (Fig. 7)- apply lagging to pipe surface (Fig. 8)(b) Vibrating pipe

15、 noiseGenerated by vibration of piping being transmitted to other parts of the building (Fig. 7)- isolate the vibration with(a) flexible coupling (Fig. 9)(b) anti-vibration isolator between pipe and its supports (Fig. 10)4. 机器发出的噪音问题成因解决方法(a) 撞击噪音因撞击如收集物料的漏斗的硬物外表所产生的噪音-用橡胶或软垫等软物作为垫子图11-减少物料下跌的高度图11(

16、b) 由震动的嵌板/皮带发出的嘎嘎声因面积大的嵌板受刺激而放射声能，例如五金啤机飞轮盖或宽传动带-使用窄带减低传动带的震动外表的面积图12-以线网盖代替飞轮盖图13-用承托蹼加强被震动的嵌板的硬度-在震动的嵌板使用具阻尼减震的材料(c) 水泵发出的嘷声噪音因水泵震动引致发出噪音-加上泵外罩图14-在水泵及地面之间加设防震器(d) 由结构传递而发出的噪音因机器的震动传递至建筑物的其它部份-在机器的底部及地基之间加设防震器图15-为雇员提供隔离室图15-在坚实的地面安装机器(e) 排气口发出的噪音因从排气口放出加压气体引致发出噪音-安装适宜的隔音罩(f) 嘈吵的机器由数个嘈杂部份导致产生噪音-提供

17、噪音隔离室，以便雇员在非实际操作嘈吵的机器时可进入该室图16-用隔音罩尽量将机器围封图17-在面对嘈吵机器的墙壁和天花加上吸音的物料，以减低反射的声音图18-在嘈吵的机器和其它雇员之间放置隔音屏障/隔声板以阻档部份噪音图19-适当保养机器-只在实际使用时才开动嘈吵的装置-增加嘈吵的机器与雇员之间的距离4. Machinery NoiseCauses of ProblemSolutions(a) Impact noiseGenerated by impact on hard surface such as the side of a collection hopper- cushion with

18、 soft material such as rubber or resilient pads (Fig.11)- reduce the material fall height (Fig.11)(b) Rattling noise from vibrating panels/beltsCaused by large panel radiating sound energy when excited, such as flywheel cover of power press or broad driving belt-reduce the size of the vibrating surf

19、ace of broad driving belt by narrow belts (Fig.12)-replace flywheel cover by wire mesh cover (Fig.13)-stiffen the vibrating panel with supporting webs-apply damping material to the vibrating panel(c) Whining pump noiseCaused by vibration of the pump-enclose the pump (Fig.14)-install anti-vibration i

20、solator between the pump base and the floor(d) Structure borne noiseCaused by vibration of machine being transmitted to other parts of the building-install anti-vibration isolator between the machine base and the foundation (Fig.15)-provide isolated room for employees (Fig.15)-Install machine on hea

21、vy floor(e) Exhaust air noiseGenerated by release of pressurised gases from exhaust- install suitable muffler(f) Noisy machineryNoise caused by several noisy parts-provide noise refuges which employees can enter when not actually operating noisy machine (Fig.16)-use acoustic enclosure to cover the m

22、achine as fully as possible (Fig.17)-line sound absorbing material on the wall and ceiling facing the noisy machine to reduce reflected sound (Fig.18)-place sound barrier/screen between the noisy machine and other employees to block part of the noise (Fig.19)-maintain machine properly-switch on nois

23、y devices only when actually in use-increase the distance between noisy machine and employees三.一般嘈吵机器的噪音控制措施嘈吵的机器控制措施(a) 塑料碎料机图20-全套隔音罩(b) 五金啤机图21-隔音罩互锁以形成啤机护罩，从而阻档公模发出的冲击声音-在啤机下装上隔震器-在气动排气口装配灭声器-将具阻尼减震材料施用于飞轮盖上-收集箱衬上柔软材料以消灭物料跌坠噪音(c) 织布机-在机器下装置隔震器(d) 精纺机-在气动收集系统装配灭声器-使用良好配件及平衡纬管-在钢环挟纱器和介轮装配隔离器(e) 圆锯

24、-鋭利刀口-正确刀口圆周速度-将具阻尼减震材料施用于刀口上(f) 手提气动混凝土破碎机图22-使用适宜的隔音罩以消灭排气噪音及从机身发出的噪音-钢钻头使用具阻尼减震材料以消灭如钟鸣的噪音(g) 空气压缩机图23-密封外罩(h) 撞击式打椿机-装上具有弹性的配件，放置在椿柱顶部以缓冲椿锤的撞击-遮盖椿柱及打椿机-减低钢椿的震动III. NOISE CONTROL MEASURES FOR COMMON NOISY MACHINESNoisy machinesControl measures(a) Plastic granulator (Fig. 20)- complete acoustic en

25、closure(b) Power Press (Fig. 21)- acoustic enclosure interlocked to form press guard to block impact sound from the tool-and- die- vibration isolators under press- silencer fitted to pneumatic exhaust- damping material supplied to the flywheel cover- collection bin lined with soft material to reduce

26、 material dropping noise(c) Weaving machine- vibration isolators under machine(d) Spinning frame- fitting of silencer to pneumatic collection system- use of well fitting and balanced bobbins- fitting of isolators to ring holders and carrier(e) Circular saw- sharp blade- correct blade peripheral spee

27、d- application of damping material to blade(f) Portable pneumatic concrete breaker (Fig. 22)- suitable muffler to reduce exhaust and body radiated noise- damping material to steel bit to reduce ringing noise(g) Air compressor (Fig. 23)- well sealed enclosure(h) Percussive piling machine- resilient packing over top of pile to cushion the blow