Industrial machines are known to possess many hazards. There are many laws, regulations, standards and practices that aim at ensuring that machines are safe for different workers performing various tasks including operation and maintenance. Safeguards protect workers by stopping hazardous motion when actuated. Those safeguards are integrated into machinery using two widely used international standards for functional safety. However, these standards have some significant differences although they are both based on similar principles. This paper explores those differences and their potential impacts. Subjectivity in the specification and design of safety systems, based on the differences, can lead to different levels of reliability in the safety systems even when considering the same hazard zone of machinery based on which standard is used.

In Québec, workers intervening in hazardous zones of machines, equipment and processes during maintenance, repairs and unjamming activities have to apply lockout procedures. Lockout procedures involve shutting down the equipment, isolating it, applying individual locks, releasing residual energies and verifying the absence of energies. Lockout has mostly been linked to industrial sectors. However, the municipal sector also faces challenges when it comes to controlling hazardous energies. The objectives of this research are to study serious accidents linked to our subject, study the application of lockout in different municipalities in Québec, identify the specificities for the municipal sector and propose some means to support the application of lockout. We will show that lockout procedures are required in different locations in municipalities and that they are currently being implemented in the municipal sector in Québec. Moreover, we propose a model which aims at facilitating the implementation of lockout procedures in the municipal sector.