Industrial Noise Control the Singapore Experience

Kia Tang TANDeputy Director (Hygiene)

Dr Magdalene O Y CHANDirector

Occupational Health DepartmentOccupational Safety and Health DivisionMinistry of Manpower, Singapore

Industrialisation -Noise Pollution: attendant necessary evil?Progressive transformation over 40 yearsFrom entrepot trade to manufacturingNow increasingly supported by information technologyOver 68,800 workers are exposed to noise in Singapore

Changing Industry Profile, Improving Trends 8-fold decline in incidence of NID (1976-2004) Decreasing noise exposure levels

No Single Solution Regulatory mechanism Training, information & guidance Incentives Engineering & technological innovations

Hearing Conservation On Wheels Raising AwarenessMobile Audiometric Testing Facility 1976-1983

Regulatory FrameworkFactories Act Effective means to reduce noise Hearing protectors Pre-employment & annual examinations Audiometry Designated Factory Doctor

Regulatory Framework

Regulations Relating to Environmental Noise LimitsMinistry of the Environment and Water Resources

Codes of Practice

Codes of Practice

Surveillance and Enforcement Activities

Incentives For Action Tax Incentive Scheme

Incentives For Action

Raising Awareness, Building CapabilitiesInformation & Guidance

Training of Competent PersonsMonitoring Facilities & Practice Standards Raising Awareness, Building Capabilities

Promotional ActivitiesReaching out to industryCollaborative projects on Hearing ConservationRaising Awareness, Building Capabilities

Sharing Best PracticesGlobal Web PortalLearning from Success Stories

Meeting the ChallengeMulti-pronged ApproachProactive StrategyFocussed EffortsLeveraging Partnerships

The role of regulatory bodies in health hazards control is to set and enforce standards, and provide the infrastructure and framework to facilitate this. However, regulatory measures alone will not achieve the desired results unless managements are committed to controlling and preventing such hazards at the plant level. This paper reviews Singapores experience in the area of noise control over the years and the impact at the national and workplace levels of various strategies and programmes, ranging from enforcement, implementation of hearing conservation programmes and training of competent persons, to promotional efforts and recognition schemes. Tan Kia Tang, BSc (Hons) (Singapore), MSc (Health Physics) (Rochester), MSc (Industrial Hygiene) (Pittsburgh)Deputy Director (Hygiene)e-mail: TAN_Kia_Tang@MOM.GOV.SG

Magdalene O Y Chan, FFOM (London), FAFOM (Australia), MSc (Occupational Medicine) (Singapore), MBBS, FAMS Director

Occupational Health DepartmentOccupational Safety and Health DivisionMinistry of Manpower, SingaporeWHO Collaborating Centre in Occupational HealthILO/CIS National Centre18 Havelock Road, #05-01 Singapore 059764http://www.mom.gov.sg/ohd

ACKNOWLEDGEMENTSWe thank Ms Lim Su Ling, Ms Angela Wu and Michael Chia for their help in the preparation of this paper. We would like to place on record our appreciation of the generous cooperation, commitment and support of all stakeholders and partners in our ongoing hearing conservation effort.While industrialisation is regarded as key to economic growth and improved living standards in developing countries, noise pollution has invariably been an attendant necessary evil. It is estimated that there are some 1,200 noisy factories in Singapore, with over 68,800 workers exposed to excessive noise. Noise Induced Deafness (NID) is the leading occupational disease, with a few hundred cases detected each year.Singapore embarked on an intensive industrialization programme over forty years ago. Since then, the economy has undergone progressive transformation from one heavily dependent on entrepot trade with only a few small-scale industries, to one with a significant manufacturing base increasingly supported by information technology. In the 1960s, many of the industries were pollutive and noisy - typically factories manufacturing textile, garments, plastic and paper products. During the 1970s, Singapores development strategy shifted emphasis from labour intensive to skill intensive industries, such as chemical, oil refining, electronics, pharmaceutical, shipbuilding and repairing. The 1980s saw a diversification into biotechnology, petrochemicals, the aerospace industry and computer peripherals manufacturing. Since the 1990s, high technology industries have been promoted in support of Singapores transition to a knowledge-based economy. Existing manufacturing plants have been upgraded, new microelectronics and wafer fabrication plants set up, and information software and multimedia companies established.

From the noise pollution angle, the changes in the industry profile over the last 10 to 20 years have been helpful in complementing Singapores noise control efforts. There are now relatively fewer noisy workplaces in Singapore. The incidence of noise induced deafness has dropped from 10.6 per 10,000 employed persons in 1976 to 1.2 in 2004. The average noise levels in workplaces monitored have decreased progressively in recent years. However, some industries continue to pose challenges. For example, in metalworking and aerospace industries, as well as steel mills, exposure levels can be as high as 105 dBA. Noisy processes that are inherently difficult to control include steel forging, engine testing, metal cutting and stamping.

There is no single solution to the control of industrial noise. While engineering and technological innovations are needed, an indispensable prerequisite to the effective control of noise is establishment of a regulatory mechanism to delineate the problem, formulate policy, enact legislation and set reasonable exposure standards for the protection of workers. However, enforcement of the law alone may not be sufficient to bring about the desired results. Resources should also be channeled to training, providing information and guidance, as well as incentives. The first NID cases in Singapore can be traced to the early 1970s when surveys revealed a high prevalence of NID among workers in textile factories, shipyards and granite quarries. As a first step to delineating the problem, NID was made notifiable under the Factories Act 19731, and compensable under the Workmens Compensation Act2 in 1975.

1. The Government of Singapore. The Factories Act 1973. The Government Printer, 1973.2. The Government of Singapore. The Workmens Compensation Act. The Government Printer, 1975.

To raise awareness and focus efforts on addressing the significant noise problem, the then Ministry of Labour, now Ministry of Manpower, launched a Hearing Conservation Programme in 1976. A central part of the programme was a mobile audiometric facility. This provided a doorstep service that enabled audiometric examinations to be conducted with minimal disruption to production schedule and at nominal cost. At the same time, workers and management were advised on the effects of noise and appropriate preventive measures. In a way, the Ministrys mobile audiometric service was a demonstration model. By 1983, the facility was phased out as a sufficient number of clinics and factories had set up their own audiometric facilities. Over the eight years, a total of 35,605 audiometric examinations was conducted, with 1,432 NID cases detected, and the NID incidence declined from 267 per 1,000 employees screened to only 10.The Factories Act, which is the main legislation safeguarding the health and safety of workers in factories, stipulates that where persons are exposed to excessive noise or vibration from any process, effective means shall as far as practicable be provided to reduce the noise or vibration. The law also requires factory occupiers to provide hearing protectors to workers exposed to excessive noise. Statutory Medical ExaminationsUnder the Factories (Medical Examinations) Regulations3, 1985, workers exposed to excessive noise are required to undergo pre-employment and annual medical examinations, including an audiometric examination. The objective of the examinations, which are conducted by a Designated Factory Doctor, is to detect early cases of NID. As at end 2004, a total of 18,056 NID cases have been detected, most in the early stages with no significant hearing disability. Only 394 (or 2%) of the cases had hearing loss sufficiently severe to warrant compensation.

3. The Government of Singapore. The Factories (Medical Examinations) Regulations. The Government Printer, 1985.

Factories (Noise) Regulations A significant development was the introduction of the Factories (Noise) Regulations4 which came into effect on 1 Jan 1997. The Regulations require factory occupiers and employers to take measures to reduce or control noise so that workers are not exposed to excessive noise. The permissible exposure limits (equivalent level of 85 dBA over an 8-hour workday) and noise control measures are specified in the Regulations. New machinery and equipment with excessive noise are not allowed unless incorporated with noise control measures. Suppliers of noisy machinery and equipment must provide information on the noise level generated by their products and label them. Factories with 10 or more workers exposed to excessive noise must appoint a competent person to conduct regular noise monitoring of at least once every three years. Factories with 50 or more workers exposed to excessive noise must appoint a suitably qualified person to advise the management on noise control measures. Persons appointed for noise control and noise monitoring must attend approved training. The Regulations also require factory occupiers and employers to provide hearing protectors to all persons exposed to excessive noise. They must put up warning signs indicating that hearing protectors must be worn in areas with excessive noise. In addition, they must institute a training programme for persons exposed to excessive noise.

4. The Government of Singapore. The Factories (Noise) Regulations. The Government Printer, 1996.

As a densely populated urban city state, Singapore places great emphasis on minimising the effects of noise pollution on the community. In the area of industrial noise pollution control, the Ministry of the Environment and Water Resources enforce the following regulations:The Public Health (Boundary Noise Limits for Factory Premises) Regulations5, 1997, stipulate factory boundary noise limits so that the noise from a factory will not affect neighbouring premises. The maximum factory boundary noise limit depends on the types of affected premises, the time of the day, and the specified duration of noise measurement. It ranges from 50 dBA for noise sensitive premises to 75 dBA for factory premises.The Environmental Pollution Control (Control of Noise at Construction Sites) Regulations6, 1999, regulate the noise levels at the boundary of construction sites. The noise levels are specified in terms of equivalent noise levels over 5 minutes, one hour and 12 hours. Different noise levels have been set for different land uses and at different times (7 am to 7 pm, 7 pm to 10 pm , and 10 pm to 7 am).

5. The Government of Singapore. The Public Health (Boundary Noise Limits for Factory Premises) Regulations. The Government Printer, 1976.6. The Government of Singapore. The Environmental Pollution Control (Control of Noise at Construction Sites) Regulations. The Government Printer, 1999.

To assist factory occupiers, employers and others in complying with the legal requirements, a number of Codes of Practice have been published. These technical documents, or Singapore Standards, published by the Singapore Productivity and Standards Board, are developed by Technical Committees, comprising representatives from relevant enforcement authorities and industries, as well as private sector professionals and the academia. The Codes include:The Code of Practice for Selection, Use, Care and Maintenance of Hearing Protectors7, 1999: provides information and guidance to persons who supply, purchase or wear hearing protectors, and sets criteria and standards on their selection, care and maintenance. The Code of Practice for Industrial Noise Control8, 2002: provides detailed technical information on noise and vibration control for acoustic specialists, plant engineers, safety and health professionals, technical personnel and those who wish to apply practical measures to control noise and vibration, as well as guidance on planning for noise control at the plant design stage. It stipulates the roles and responsibilities of factory occupiers and appointed competent persons with respect to noise monitoring, noise control planning and noise hazard management. The Code includes worked examples on engineering noise control such as the use of acoustic barriers, enclosures, partition walls, silencers, isolators, sound absorbing and damping materials.

7. Code of Practice for Selection, Use, Care and Maintenance of Hearing Protectors. Singapore Productivity and Standards Board, 1999. 8. Code of Practice for Industrial Noise Control. Singapore Productivity and Standards Board. Singapore Productivity and Standards Board, 2002.

The Code of Practice for Noise Control on Construction and Demolition Sites9, introduced in 1989 and revised in 1998: provides information on measures that can be adopted to reduce noise from various construction and demolition equipment. It also provides information on estimation of noise levels from work and methods of noise monitoring. The Code highlights the importance of minimizing construction noise to protect site personnel and nearby residents, and recommends measures to be taken at the planning, design, tender and construction stages.

9. Code of Practice for Noise Control on Construction and Demolition Sites. Singapore Productivity and Standards Board, 1998.

Factories applying for factory registration are inspected to ensure that minimum health standards are provided before they start operation. With finite resources, a selective enforcement approach is necessary. Hence, surveillance and enforcement activities are targeted at potentially noisy industries, specifically - textile, food and beverages, wood and wood products, paper and paper products, printing and publishing, metal and fabricated metal products, non-metallic mineral products, machinery and equipment, chemical and chemical products, rubber and plastic products.With the introduction of the Factories (Noise) Regulations in 1996, the Ministry of Manpower implemented a noise enforcement programme, with specific focus on machinery noise labelling, noise control, and evaluation of reports on noise assessments and control planning submitted by factories. A database on occupational noise exposure was established by the Ministry in 1996, to provide a national focal point for information on noise exposure in high risk workplaces. Inputs are results from assessments conducted by the Ministry, as well as those from regular monitoring by factories. As at end 2004, the database contained 15,339 assessment results. Many of the NID cases could have been prevented if effective measures were taken to prevent or control the noise hazard. Proven technology and engineering controls provide the most effective solutions to the elimination or reduction of noise hazards. However, the cost of implementing such measures can be significant, particularly for small and medium enterprises. To encourage companies in implementing noise control measures, recognition and incentive schemes have been established.Tax Incentive SchemeA Tax Incentive Scheme for Noise Control was introduced with effect from Year of Assessment 1999. The objective of the scheme is to help factories partially defray the cost of implementing engineering measures to control noise. A similar scheme has also been introduced for control of chemical hazard. The tax incentives mark an important milestone. For the first time, companies that invest in controlling occupational health hazards could expect financial assistance. Under the scheme, factory owners or occupiers can apply for a one-year accelerated depreciation allowance if they have, on or after 1 Jan 1998, purchased or installed equipment or technology for noise control that meet the prescribed criteria i.e. purchase of low-decibel new machinery, e.g. stamping machines and concrete crushers, or installation of noise control equipment such as acoustic enclosures and silencers. The noise level must be at or below 82 dBA which is 3 dBA lower than the current permissible exposure limit of 85 dBA. Thus, the scheme promotes the achievement of noise control standards that are better than what is required in the law. So far, a number of companies have taken advantage of the scheme, although the majority of companies have been able to implement effective noise control measures without relying on the scheme. Clearly, in most situations, the control measures were relatively inexpensive. Noise Control AwardsTo give further impetus to noise control efforts at the plant level, the Ministry introduced a Noise Control Awards (NCA) scheme in 1999. The awards comprised three categories:Excellence Award: for companies that have made outstanding achievements in noise control at the workplace. To qualify for this award, the noise level in the entire premises must be below 85 dBA, the noise reduction (NR) should be at least 6 dBA per source, and the total NR should be at least 10 dBA.Merit Award: for companies that have made significant achievements in noise control at the workplace. The criteria are similar to that of the Excellence Award except that the noise level in the premises must be below 90 dBA, and there must be an effective hearing conservation programme implemented.Innovation Award: introduced in 2003 to encourage companies to apply creative or innovative ideas, methods or techniques to control noise.Over the years, the biennial awards scheme received increasing support, with a total of 29 companies receiving recognition for their efforts in controlling noise seven in 1999, 10 in 2001 and 12 in 2003. Following the success of the NCA, the scheme has been incorporated into a wider recognition system - the Occupational Health Best Practices (OHBP) Award. The inaugural OHBP Awards presented in October 2004, featured both Noise and Chemical Control categories, and saw 15 companies winning in the Noise Control category. The objective of the new scheme is to encourage companies to address not only noise, but other health hazards as well, and an Ergonomics Solutions category will be included from 2005. The main impediments to hearing conservation efforts are lack of awareness of the risk, as well as inadequate resources and expertise for noise control at the plant level. Over the years, the Ministry has produced a number of guidelines and educational materials for managers and workers. Some of the guidelines have been refined and adopted as Codes of Practice, having been implemented by the industry on a self-regulatory basis for a period of time.

The Ministry collaborates with relevant agencies, employers organisations and unions in various training and promotional activities. Information leaflets on hearing protectors and pamphlets on NID are distributed to factories with noise problems. To cater to the multilingual local and migrant workforce, the materials are produced in various languages.Information and Guidance The following guidelines and educational materials are available on the Ministrys website: Guidelines on Industrial Noise and Vibration ControlGuidelines on an Effective Hearing Conservation ProgrammeGuidelines on Noise Labelling Fact Sheets on Noise-induced Deafness and the Factories (Noise) Regulations 1996

Training of Competent Persons The development of competencies in key personnel is important to enable factories to comply with legal requirements. Six approved training centres conduct training courses on noise monitoring and noise control for competent persons. The duration of each course is three days. As at end 2004, a total of 757 and 347 persons attended the required training courses on Noise Monitoring and Noise Control, respectively, conducted by the approved training centres. Training courses have also been conducted on noise emission testing and labelling.

Persons conducting audiometric screening of workers exposed to noise undergo approved training. So far, over 380 persons have been trained. There are currently 12 clinics with audiometric testing facilities and five mobile audiometric service providers. The Ministry of Manpower monitors the practice standards of such competent persons and ensures that the testing facilities meet requirements.

Promotional ActivitiesPrior to the introduction of the Factories (Noise) Regulations, a series of publicity and promotional activities were organised in 1996 and 1997, to inform the industry of the impending legislation and to educate workers on the hazard of industrial noise. These included conferences and seminars, feature articles and programmes over the mass media. In 1999, the National Trades Union Congress initiated a project on Hearing Conservation with the objective of reducing noise levels at work and protecting the hearing of employees. Initially, 15 engineering companies participated in the project. A Memorandum of Understanding was signed by the management of the participating companies and representatives from the union and the Manpower Ministry.The key components of the programme include monitoring of noise levels, implementation of noise control measures, conducting health education talks, and supervision of hearing protection and hearing tests. Most of the participating companies have implemented the programme and there have been inspiring success stories. Two companies received the Noise Control (Excellence) Award in 2001. Since the programmes re-launch in May 2002, more companies from the aerospace, metalworking, electronics and shipbuilding & repairing industries have come on board, bringing the total number of companies under the programme to 36.

Sharing Best PracticesLearning from success stories motivates and often generates more and better solutions. To facilitate information sharing, the Ministry has established a repository of successful cases of health hazards control, including noise control.Publications and CD compilations of such cases document noise control using various engineering measures, including acoustic enclosures, sound barriers, flow regulators, silencers and machine substitutions. The case studies are available on the internet through Singapores recently established link to the WHO Global Web Portal aimed at complementing the Programme of the Network of WHO Collaborating Centres in Occupational Health. The control of industrial noise and prevention of NID is difficult but not impossible. A multi-pronged approach, involving regulatory, promotional and incentive measures, is necessary to tackle the problem at the national level. The role of regulatory bodies is to set and enforce standards, and provide the infrastructure to facilitate noise control. The joint efforts of government, the trade unions and employers organisations are needed to establish effective noise control and hearing conservation programmes in industry. Such efforts would yield the desired results if managements are committed to protecting the health of their employees and appreciate that noise control is sound business. While enforcement action may be needed get the job done, promotional activities, incentives and recognition of efforts are effective motivators. Singapore has adopted a proactive, partnership approach in the control of noise and prevention of NID. The measures and initiatives discussed have been helpful in addressing the problem of excessive noise in workplaces. The results have been encouraging but more work lies ahead, as we focus our efforts on controlling inherently challenging problems in certain noisy processes and industries.