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A code for guarding against BEZ breaches

Unfortunately, these statistics are not unique to Western Australia, and this problem is common in other states and territories. In response to the high number of incidents, the Australian Explosives Industries Safety Group (AEISG) has produced a code of good practice on blast guarding in open-cut mining. The first edition – Blast Guarding in an Open Cut Mining Environment ? was first released in March 2011 and is available from both the Department and AEISG?s websites.
{{image2-a:r-w:250}}The code was gazetted by the Department on 14 September, 2012 as an approved code of practice following approval by the Minister under section 20 of the Dangerous Goods Safety Act (Western Australia) 2004. Under section 8 of the Act, there is a duty of care on licence holders to minimise risk to people, property and the environment. Compliance with this code demonstrates that reasonable precautions are being taken to minimise risk.
Where an investigation or audit indicates the code has not been complied with or there are deviations from its requirements, the onus is on the licence holder to demonstrate that the changes have not led to a decrease in the level of safety and security as defined in the code.
It may appear a relatively simple task to clear all personnel (and possibly equipment) from within the blast exclusion zone, fire the shot, let the flyrock settle, check whether it is safe for people to re-enter the blast area and, if so, give the ?all clear? for workers to recommence their operations. However, the number of incidents suggests that this is not the case, possibly due to:
  • Poor or non-existent communication between the parties involved.
  • A lack of robust systems such as a standard operating procedure (SOP) to secure the blast exclusion zone.
  • A lack of or inadequate training.
The roles of those involved in the blasting process is described in the code, including:
  • The shotfirer who initiates the shot.
  • The blast controller who organises the logistics and provides support so the shotfirer can concentrate on firing the shot.
  • The blast guard who is the sentry and provides a barrier to prevent people from entering the blast exclusion zone.
  • The code also contains information on the roles of the blast designers, drill and blast supervisors and mine managers.
The code describes in detail the mechanics of establishing and securing a blast exclusion zone so it is safe to execute the blast. 
This includes:
  • The equipment required to properly perform the operation.
  • The preparation of a scaled plan of the blast exclusion zone based on a risk assessment showing where the shotfirer will fire the shot and where the blast guards will take up position, taking into account wind directions and fume production.
  • The requirements to notify people on the mine, at least one day before the intended blast.
  • A pre-blast meeting for the shotfirer, blast controller and blast guards at the blast site an hour before the blast. This ensures that everyone is aware of their duties and the equipment is operational.
  • The blast guards clearing the blast exclusion zone and setting up position at their nominated locations.
  • The blast controller conducting a final sweep of the area before handing control of the blast back to the shotfirer.
  • The calls the shotfirer must make, including making contact with the blast guards.
  • How to deal with breaches of the blast exclusion zone and other emergencies.
  • Firing the shot, waiting until it is safe to enter and checking that it is safe before the ?all clear? is given.
  • The protocol for dismissing the blast guards when it is safe to re-enter the site.
  • How to deal with misfires when the ?all clear? cannot be given.
Although Australian Standard AS 2187.2 Explosives ? Storage and use ? Use of explosives allows the shotfirer to enter the blast exclusion zone if it is safe to do so, the code indicates that the shotfirer must fire the shot from outside the blast exclusion zone. The Department recommends that the shotfirer remains outside the zone but within the area under the blast guards? control. 
Too many incidents have occurred where the zone has been cleared and the shotfirer re-enters it to have direct line of sight to the blast.
The Department recommends that companies have a SOP based on the code for blasting. Where companies already have a SOP for blasting, it is recommended that it be reviewed against the code, a gap analysis conducted and the SOP updated to reflect the requirements of the code.
Another reason for having a comprehensive SOP for blast guarding is for training purposes. The code requires people involved in these roles to be properly trained and the SOP can form the basis of this training. Once trained, a register should be kept of all blast controllers and blast guards, including when refresher training is required. Training should also cover:
  • The use of site radios, including channels to be used and call signs.
  • How to deal with breaches of the blast exclusion zone, emphasising that guards cannot leave their posts under any circumstances.
  • How to deal with emergencies.
  • Ensuring personnel can operate all equipment involved in the process, including light vehicles.
Effective communication between all those involved in the intended blast as well as the general mine workforce is the key to ensuring lives are not put at risk. The AEISG code provides practical, easy to follow information on effective blast guarding so blasts can be fired safely.
Anyone involved in blasting is encouraged to download a free copy of Blast Guarding in an Open Cut Mining Environment and become familiar with its content and how to use it.
This article originally appeared in Resource Safety Matters 1(3), September 2013, published by the Resources Safety Division of the WA Department of Mines and Petroleum (DMP). It appears in Quarry with DMP?s kind permission.

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