Developing an integrated decision making approach to assess and promote the effectiveness of occupational health and safety management systems

• We developed an appropriate tool that helps managers to provide useful information for continuous improvement of OHSAS 18001.
• The proposed method covers broad scope of OHS issues and could predict future of OHSAS 18001.
• We determined usable criteria and related indicators for assessing OHSAS 18001 effectiveness.
• OHSAS 18001 implementation is a gradual process.

Occupational Health and Safety Assessment Series (OHSAS) 18001 standard has been recommended as a tool for managing and controlling occupational risks through a systematic and structured management. However, controversy exists as to the effectiveness of OHSAS 18001 in reducing occupational risks at workplace. The current study introduces an integrated decision making approach by merging two techniques including Analytical Network Process (ANP) and Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) to assess and improve the effectiveness of OHSAS 18001 standard. Our findings indicate that the most influential factors to be taken into account to improve the effectiveness of OHSAS 18001 standard are management commitment, workers' participation, allocation financial resources, training, risk assessment, definite responsibility, communication and dissemination of occupational health and safety results and activities. The study offers this approach as a tool to evaluate and promote the effectiveness of OHSAS 18001 standard.