# Noise Sources and Control, and Exposure Groups in Chemical Manufacturing Plants
## 4 Discussion
### Hearing Protection Devices
#### 4.3.2 Costs and Benefits of Noise Control and Regulation  
The implementation of noise control and other aspects of noise regulations place a financial and compliance burdens on employers. However, this should not discourage employers from implementing feasible engineering noise controls. The annual costs for the manufacturing sector in the US relating to compliance with the occupational noise standard in 1993 were estimated by OSHA to be around $210.3 million. The compliance costs for each enterprise in the sector were also estimated at $638 thousand based on the 1993 dollar terms. On the other hand, the costs related to HPDs required for compliance with the same standard were estimated at $34.2 million. The overall estimated compliance costs to OSHA-related regulations in the US in 1993 were estimated between $23.1 billion and $46.7 billion [138].  
In the UK, the final regulatory impact assessment of the control of noise at work regulations 2005, also estimated compliance costs segregated into costs related to familiarisation, assessments, information, preparation of programme, reducing exposure, HPDs, signage and audiometric testing. On the first year on implementation, employer costs were estimated between $117 million to $202.6 million, whilst the 10 year costs were estimated to be between $477.6 million to $676.3 million. The highest cost item predictably related to the implementation of engineering controls was estimated at between $27.5 million to $109.9 million in the first year, and increased to between $65.2 million to $268 million for the 10-year cost period. The HSE estimates employer costs for each noise-exposed worker at $35.60. [139].  
There however remains limited studies detailing the exact overall costs of compliance to all occupational health and safety regulations [132]. This is true for SA where there are no publicly available cost estimates and benefits of implementing occupational health and safety regulations inclusive of the NIHL regulations. Notwithstanding the costs relating to compliance to the NIHL regulations, employers and the government in SA should play their legal roles of ensuring that the good intentions of these regulations are met. Afterall, these regulations were enacted into law following extensive deliberations and agreements amongst the tripartite structure inclusive of government, labour and unions.  
The benefits of noise control and regulation are however not immediately visible due to the delayed onset of NIHL. However, an ancillary and tangible benefit of noise control and regulation is that it highlights the important role played by professions such as occupational hygiists in workplace health and safety programmes [140]. The benefit of a noise control measure to a worker however requires noise quantification through dosimetry measurements before and after the intervention [141]. In general, the costs of occupational safety and health actions are easily visible compared to benefits which tend to be underestimated. Additionally, the return on investment related to occupational health and safety compliance initiatives is influenced by an enterprise's current practice, implying that an enterprise with a dismal practice in noise control and prevention will notice major spinoffs for a small investment made to address the same issues [142].