OHS Code Explanation Guide

Published Date: July 01, 2009
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Part 15 Managing the Control of Hazardous Energy

Section 215.1 Securing by complex group control

In some cases it may not be reasonably practicable to use an individual or group lock out process. To maintain worker safety, normal group lock out practices may need to be adapted or modified. A complex group control process allows an employer to do this.

The complex group control process relies on written procedures and a work permit or master tag procedure to ensure the safety of workers. These two elements replace the traditional approach of each worker placing a personal lock on each energy-isolating device or on a group lock box.

The reasons for choosing to use a complex group control process most likely involve a combination of several of the following factors:

(1) the physical size and extent of the machinery, equipment, piping, pipeline or process system – the machinery, equipment, etc. may occupy such a large area, or occupy multiple areas, that it becomes impractical for all affected workers to apply their personal locks to all the energy-isolating devices. This usually results in the employer using a group lock out process but may, based on the other factors listed, lead to the use of a complex group process;

(2) the relative inaccessibility of the energy-isolating devices – some energy-isolating devices may be difficult to access and the act of getting to and from them could potentially expose workers to hazardous situations or conditions e.g. fall hazards, confined space entry hazards, exposure to elevated noise levels, etc. Eliminating this unnecessary exposure may be a good reason for choosing to use a complex group control process;

(3) the number of workers involved in the work requiring hazardous energy control – at some point so many workers may be involved in the work that using group lock boxes and their accessories becomes impractical. This may occur in situations such as plant shut downs when significant numbers of workers new to the work site begin working there;

(4) the number of energy-isolating devices involved – so many energy-isolating devices may be involved that it is impractical for all affected workers to apply their personal locks to all of them. This usually results in the employer using a group lock out process but may, based on the other factors listed, lead to the use of a complex group process;

(5) an extended length of time of the isolation – an extended or lengthy lock out period may prevent personal locks from being put to use elsewhere, requiring an employer to issue additional personal locks to workers; or

(6) the interdependence and interrelationship of the components in the system or between different systems – the system or systems being locked out may be so complex that from the safety and efficiency perspectives, using a complex group control process makes the most sense.

An employer wanting to use a complex group process must have it approved by a Director of Inspection. A Director of Inspection is a member of the staff of Alberta Human Services appointed by the Minister under section 5 of the OHS Act. A Director of Inspection reviews the employer’s application to ensure that the level of protection provided to workers is at least equivalent to that provided by the individual or group process.

An application for approval must include:

(a) a rationale for using a complex group process, answering the question “Why is individual or group lockout not practical?”,
(b) a copy of the hazard assessment completed in accordance with Part 2 of the OHS Code,
(c) a summary or copy of the procedures to be used that ensure continuous safe performance of the work,
(d) a thorough description of the work permit or master tag system to be used, and
(e) recognition of a worker’s right to place a personal lock on an energy-isolating device(s) despite the permit or master tag system (see subsection 215.1(4)).

Approval is not required each time a complex group process is used unless there are substantive differences from the approved process.

The Director of Inspection can be reached by writing to:

Director of Inspection
Alberta Human Services
Workplace Standards Division
8th Floor, 10808-99 Avenue
Edmonton, Alberta T5K 0G5

A worker designated by the employer (typically a supervisor or crew leader), carries out the isolation by activating and securing all energy-isolating devices. Another worker, designated by the employer, is responsible for verifying that the isolation is effective.

To ensure the safety of all workers involved in the lock out process, the work permit or master tag system being used requires that

(1) each involved worker personally signs on and off the job, or
(2) a crew leader signs on and off the job on behalf of a crew or team of workers.

When complex group control is used, each worker must be allowed the option of placing a personal lock on the lockable securing device and then verifying isolation.

Upon completing the work, each involved worker must be accounted for before locks are removed. The worker authorized by the employer to do so must verify that no workers are in danger due to the locks/isolating devices being removed and the machinery, equipment, piping, pipeline or process system being returned to operation.

Verifying isolation

Subsection 215.1(3)(d) requires that a second worker, designated by the employer, confirms that all energy sources in a complex group control situation are effectively isolated.

The purpose of the second worker’s action is to verify that all hazardous energy sources that could cause injury due to unintended motion, energizing, start-up or release of residual energy (see OHS Code definition of “hazardous energy”), are effectively isolated. Verification may be achieved by testing circuitry, attempting to cycle machinery, visual inspection, monitoring movement or discharge, observing bleeds, gauges or indicators, or other equally effective approaches. The approach used should offer the best degree of assurance that isolation has been achieved.

The second worker is not confirming that the first worker physically placed the locks in the correct location. The second worker is making sure that the placement of the locks has resulted in the energy sources being effectively isolated. Having a second worker confirm that locks are physically placed in the correct locations is not the same as verifying that all energy sources are effectively isolated.