Lockout Procedures Research Articles

Design of a Self-Audit Tool for the Application of Lockout on Machinery in the Province of Quebec, Canada to Control Hazardous Energies

Failure to apply lockout procedures for the control of hazardous energies is one of the main causes of machinery-related fatal and serious injuries in North America. The absence of audits of lockout or the lack of proper tools for auditing lockout is prevalent, and thus the application of lockout is often not fully in compliance with standards and regulations. A self-audit tool for the application of lockout procedures for machinery was developed on the basis of the current standards and regulations, and previous research. The tool was then tested for content validity through experts’ opinions and qualitative feedback from six organizations in the province of Quebec in Canada. The developed audit tool defines the actual procedures to audit, as well as the surrounding conditions that are needed and the prerequisites based on standards, regulations, and findings from previous research. The results showed that the tool displayed a high content validity index and demonstrated that the usability, applicability, and comprehensiveness of the tool were adequate. This self-audit tool helps organizations monitor the application of lockout on machinery for the safety of workers and to ensure that the actual practice of controlling hazardous energy is in compliance with relevant standards and regulations.

Qualitative study on the control of hazardous energy on machinery using lockout and alternative methods

In Canada, like many countries, the national standard and provincial regulations require that workers performing maintenance, repair, and un-jamming activities on machinery must follow lockout procedures. However, the high number of accidents linked to hazardous energies and machinery shows that organizations have difficulty with the application of lockout arrangements or use of alternative methods. Therefore, it is important to understand how organizations implement lockout programs and procedures, and the extent to which they are in accordance with relevant standards and regulations. In this qualitative research, the application of lockout and alternative methods was studied in 13 organizations in Quebec, through a group interview, document review and site observation in each organization. In each organiztion, the researchers conducted a group interview and completed a questionnaire, which included more than a hundred questions on the lockout program, application of lockout procedures, alternative methods, sub-contractor management, training, and audit/inspection. The researchers then used observation data and documentation collected from each organization to verify interviewee responses and to finalize the questionnaire. The shortcomings found included: (i) incomplete lockout programs; (ii) missing steps in general lockout procedures; (iii) not reading the placards; (iv) using alternative methods without risk assessment; (v) poor training for alternative methods; (vi) absence of supervision and coordination of subcontractors; (vii) and lack of audit tools and documentation of audit results. Despite the shortcomings, actual lockout practices in the organizations visited were better than what was described in their lockout programs. Recommendations for addressing identified shortcomings are proposed.

Design of a safety control system to improve the verification step in machinery lockout procedures: A case study

In Canada and other industrialized countries, workers who are required to carry out tasks in the danger zone of a machine when performing repairs, maintenance or unjamming activities must follow lockout procedures, unless safe alternative methods exist and can be applied. The verification step in lockout procedures is often neglected by workers for various reasons. This paper presents the design process for a new, reliable safety control system for the verification step. The design will allow automatic verification of zero electrical energy in the machine. Consequently, little effort will be required by workers to carry out this important step in the lockout procedure. Moreover, energy-saving systems create additional difficulties for lockout. This case study involves a paperboard extruder used to apply plastic on paperboard. It uses a DC bus that links the speed drives together as an energy-saving measure. This paper details for the first time the design and validation steps specified in ISO 13849-1 and 2 when using a programmable safety control system to improve the lockout verification step. The approach adopted here can be used for other machines and will help improve worker safety during interventions by ensuring correct application of the lockout procedure. The system described here was designed prior to publication of the 2015 version of ISO 13849-1. Accordingly, it was designed in compliance with the 2006 version of this standard, which directly preceded the 2015 version.

Managing risks linked to machinery in sawmills by controlling hazardous energies: Theory and practice in eight sawmills

Machines pose various types of hazards and exposure to these hazards can result in injury or death. Risks linked to machinery can be managed by controlling hazardous energies. Safety procedures are thus used to control hazardous energies on machinery when workers perform different tasks such as maintenance, unjamming, or repair work. These procedures are part of a safety management policy for hazardous energies. The policy is described in a document referred to as the lockout program, which includes activities and work targeted by lockout, audits, hazard identification, training, communication and so on. The objective of this paper is to understand how the lockout program is actually implemented. As such, seven lockout programs from eight sawmills were analyzed. Twenty-two interviews were conducted with machine operators, maintenance workers and managers to gain a better understanding of the actual application of lockout programs, identify weak points and propose improvements. Fifty-seven lockout procedures were also observed. It was found that (i) hazard identification was incomplete, (ii) lockout program signatures and dates were missing, (iii) actual lockout practices were better than the procedures described in the programs regarding lockout hardware, rules to observe when using lockout hardware (e.g. keeping keys in one’s possession at all times) and machinery design for facilitating lockout, (iv) locks were applied to control systems during minor unjamming contrary to lockout principles, and (v) permits were issued as alternatives to lockout for troubleshooting without risk assessment. In actual fact, risk assessment is needed for both interventions requiring lockout and those without lockout.

Analysis and prevention of serious and fatal accidents related to moving parts of machinery

Machines contain hazards of different nature and exposure to those hazards can result in injuries or deaths. Safety of machinery considers the ability of a machine to perform its intended function during its life cycle where risk has been adequately reduced. The principles of machine safety, risk assessment and risk reduction are covered in international standards, national standards, regulations and other literature. Moving parts of machinery still cause many serious injuries and fatalities. This paper aims at analyzing serious injuries and fatalities related to moving parts of machinery in order to understand the various reasons causing such accidents. As such, 106 accident reports related to moving parts of machinery from the province of Quebec in Canada have been analyzed. The main causes are easy access to moving parts of machinery, lack of safeguarding, absence of lockout procedures, inexperience of workers, bypassing safeguards, lack of risk assessment, lack of supervision, poor machinery design, unsafe working methods, no clear instructions to workers on how to intervene safely on machinery as well as modifications to machinery and to control systems. Prevention strategies are also proposed based on the findings and on the literature.

Observation and analysis of 57 lockout procedures applied to machinery in 8 sawmills

Occupational health and safety regulations require the application of lockout procedures to prevent injuries and fatalities in Canada and in other countries. Absences of lockout procedures or incorrect lockout procedures are linked to many accidents involving machinery in the literature. This paper presents the findings of qualitative research which examined how workers involved in repairs, maintenance or unjamming activities inside or around hazardous zones of machinery apply lockout procedures. This subject was investigated in 8 sawmills in Quebec by observing the application of 57 lockout procedures. Based on the observations, it can be said that important steps in the lockout procedures are omitted. Some interventions are carried out without lockout procedures, exposing workers to hazards. Machine safeguarding in sawmills presents serious flaws and the safety of workers depend heavily on correct lockout procedures.

Design of an Intelligent Tool for the Observation and Follow-Up of Lockout Procedures during Maintenance Activities on Industrial Machines

Workers performing maintenance, repair and un-jamming operations on industrial machines and processes are required to follow lockout procedures in accordance with occupational health and safety regulations. However, industries seem to have difficulties in the appropriation and implementation of lockout. Reports of severe accidents, often fatal, involving industrial machinery show the extent of the problem concerning the application of lockout procedures. In this context, an intelligent tool incorporated at the design stage of a machine, which helps to apply and record lockout procedures, could be useful. Thereby, the design of a laboratory prototype has been explored for a particular maintenance task on an automated plastic injection moulding machine. Its architecture has been based on three electronic cards, sensors and wireless communications. Despite the limitations of the current version of the tool, the feasibility of designing an intelligent tool capable of following and recording lockout procedures is demonstrated.

Study on Lockout Procedures for the Safety of Workers Intervening on Equipment in the Municipal Sector in Québec

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.

Lockout and Tagout Procedures to Prevent Occupational Injury and Fatality

Hazardous energy control programs that include lockout and tagout procedures as well as worker training can prevent serious injury and death during machine maintenance.

Circumstances of fatal lockout/tagout‐related injuries in manufacturing

Over the past few decades, hundreds of manufacturing workers have suffered fatal injuries while performing maintenance and servicing on machinery and equipment. Using lockout/tagout procedures could have prevented many of these deaths. A narrative text analysis of OSHA accident investigation report summaries was conducted to describe the circumstances of lockout/tagout-related fatalities occurring in the US manufacturing industry from 1984 to 1997. The most common mechanisms of injury were being caught in or between parts of equipment, electrocution, and being struck by or against objects. Typical scenarios included cleaning a mixer or blender, cleaning a conveyor, and installing or disassembling electrical equipment. Lockout procedures were not even attempted in the majority (at least 58.8%) of fatal incidents reviewed. Lockout/tagout-related fatalities occur under a wide range of circumstances. Enhanced training and equipment designs that facilitate lockout and minimize worker contact with machine parts may prevent many lockout/tagout-related injuries.