Blast management plans - WorkSafe Victoria
Guidance note
Blast management plans Advice on developing a blast management plan to control risk from explosive blasting.
April 2011
Background A blast management plan (BMP) is a risk control plan used in explosive blasting. It aims to ensure blasts do not harm people in the area and limit damage to the environment. A BMP is prepared by the shot firer before every blast and after consulting those involved in the blast. A BMP is the recommended method for planning safe use of explosives.
Requirements of a blast management plan The BMP should meet the following requirements, set out in AS 2187.2: Explosives - Storage and use. Part 2: Use of explosives: • explain the objectives of the blast • identify hazards and risks, including control and/or mitigation • identify site-specific requirements • introduce the blast as part of the overall task in a planned manner • control the blast process from design to initiation and in the event of a misfire • comply with the approval/contract specifications • ensure safety of the public, site personnel and surrounding properties • implement a review process to ensure that the objectives are met. The detail in the BMP depends on the size, location, nature and complexity of the blasting operation. It may be part of a site safety plan to address all hazards and risks at the site. See below for examples of information to include in a BMP.
What is the objective of the blast? A statement is required about what the blast is going to achieve. Is it for demolition, extraction of ore, civil works or other work? The type of work will indicate the key safety and environment risks that will need to be considered. Points to consider include: • type of explosives and the method used to fire them • whether the blast is in a built-up area or a remote location • date and time of the blast • number of people and equipment involved
GUI0144/01/04.11
• • • • •
location and layout of the blast area access to the blast area description of the proposed blast permits/licences required details of adjacent structures/services.
How are risks assessed and controlled? A thorough, documented risk assessment is necessary to ensure the risks have been reduced using existing risk controls (see table over page for examples) or new or additional control measures have to be devised and implemented.
What are the specific requirements for the site? Each site will have different requirements such as level of personnel required. In most cases, the following people, with the appropriate level of competence and experience, have responsibility for planning, preparation and conduct of aspects of the blast: • shot firer (author of the BMP) • person responsible for the blast, including safety and security (usually the shot firer) • person giving approval to use explosives on site • other key people (eg site supervisor). The shot firer must hold a current WorkSafe Victoria licence authorising a person to use blasting explosives. For licensing information, go to the licensing webpage on the WorkSafe Victoria website worksafe.vic.gov.au Blasting on construction sites requires preparation of a safe work method statement to identify risks and describe risk controls measures, if there is a risk to health and safety. Other information specific for the site will relate to the location of the site (eg how close the blast is to any structures, services, public areas and other work areas) and what changes may be needed to ensure there is no danger to the public or risk of damage to structures or the environment. If blasting is for demolition of buildings and other structures, those conducting the blasting must notify WorkSafe Victoria in writing 21 days before the demolition. The notification has to include the demolition plan which details all relevant information specified in Appendix K of AS 2187.2
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Guidance Note Blast management plans
Table 1 - Common risks and risk control measures to consider for a blast management plan Identified risk
Risk controls
Unauthorised access to blast area
• Security arrangements in place, such as access to authorised persons only and secured area with guarded gate.
Unauthorised access to explosives • Secure stores store/portable magazine • Security arrangement to prevent unauthorised access. Inadequate training and competency for staff
• • • •
Ensure shot firers are licensed. Train personnel in explosives products and blast design. Use tools to test blast eg model blast pattern technology tool. Develop and implement procedures to check training and competency.
Competency of contractors
• Review competency and training. • Set minimum standards. • State requirements in contracts.
Blasting procedure
• Develop and maintain safe blasting procedures. • Involve competent people in development.
Inconsistency in performance of explosives
• • • •
Use reliable supplier. Test explosives. Develop procedures for use of explosives. Ensure shot firers are licensed and experienced.
Unreliable firing methods
• • • •
Use reliable products. Test safety fuses, if used, and other equipment. Ensure equipment is maintained by competent people. Develop procedures for checking firing method.
Hot ground causing premature firing
• Use appropriate firing method and types of explosives. • Test in hot conditions. • Check ground before designing the blast.
Damage to structures
• Evaluate the affect of ground vibration and air blast overpressure on structures or ground conditions. • Revise blasting procedure to minimise damage.
Risk of fly rock
• Calculate quantity of explosives, stemming and capping. • Set up exclusion zones. • Use blast mats.
How will the blast be prepared and fired safely?
• details of reports, drawings and records consulted • post blast assessment and inspection procedures.
The BMP needs to describe the design of the blast necessary for the task and what procedures will ensure the charge is prepared and fired safely. This information includes: • layout of the blast including the drilling pattern and hole depth • drilling procedure • explosives type/quantity, firing equipment and method • procedures for loading and charging • detonation sequence/effective charge mass per delay (MIC) ‘powder factor’ • misfire procedure
What security is required? Security arrangements are necessary to meet the requirement in the BMP to ensure safety of workers, the public near the site and surrounding properties if in a built-up area. Arrangements will need to prevent unauthorised people entering the site and gaining access to the explosives to be used in the blast. The site should remain secure until the shot firer is satisfied the area is safe after the blast.
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Guidance Note Blast management plans
Other security matters to consider include: • setting up the exclusion zone • the communications system required for those involved in the blast • a plan to manage traffic around the site • information for owners/occupiers of structures, providers of services and neighbours • warning systems eg sirens • explosive storage and handling procedures.
Record keeping The results of each blast should be recorded and kept. This information assists in the planning and implementation of further blasts and provides documentation in case of incident or complaint. Records should include: • if tunnel blasting, presence of any hazardous atmospheres and inrush • environmental conditions at the time of the blast (eg rain) • measurements from the blast equipment and/or monitoring equipment (eg vibration and noise) • details of fly rock or fly • incidents and complaints • results of the blast • proposed modification to the blast plan for future blasts.
Further information Contact the WorkSafe Victoria Advisory Service on 1800 136 089 or go to worksafe.vic.gov.au More information • AS 2187.2: Explosives – Storage and use. Part 2: Use of explosives and Appendix K – Demolition of structures • Resources Safety (WA) guide, Guide to blast plan preparation, including mining operations • WorkSafe Victoria Guidance Note: Safe distances when using blasting explosives.
Note: This guidance material has been prepared using the best information available to the Victorian WorkCover Authority and should be used for general use only. Any information about legislative obligations or responsibilities included in this material is only applicable to the circumstances described in the material. You should always check the legislation referred to in this material and make your own judgement about what action you may need to take to ensure you have complied with the law. Accordingly, the Victorian WorkCover Authority cannot be held responsible and extends no warranties as to the suitability of the information for your specific circumstances; or actions taken by third parties as a result of information contained in the guidance material. WorkSafe Victoria is a trading name of the Victorian WorkCover Authority.
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Blast management plans Advice on developing a blast management plan to control risk from explosive blasting.
April 2011
Background A blast management plan (BMP) is a risk control plan used in explosive blasting. It aims to ensure blasts do not harm people in the area and limit damage to the environment. A BMP is prepared by the shot firer before every blast and after consulting those involved in the blast. A BMP is the recommended method for planning safe use of explosives.
Requirements of a blast management plan The BMP should meet the following requirements, set out in AS 2187.2: Explosives - Storage and use. Part 2: Use of explosives: • explain the objectives of the blast • identify hazards and risks, including control and/or mitigation • identify site-specific requirements • introduce the blast as part of the overall task in a planned manner • control the blast process from design to initiation and in the event of a misfire • comply with the approval/contract specifications • ensure safety of the public, site personnel and surrounding properties • implement a review process to ensure that the objectives are met. The detail in the BMP depends on the size, location, nature and complexity of the blasting operation. It may be part of a site safety plan to address all hazards and risks at the site. See below for examples of information to include in a BMP.
What is the objective of the blast? A statement is required about what the blast is going to achieve. Is it for demolition, extraction of ore, civil works or other work? The type of work will indicate the key safety and environment risks that will need to be considered. Points to consider include: • type of explosives and the method used to fire them • whether the blast is in a built-up area or a remote location • date and time of the blast • number of people and equipment involved
GUI0144/01/04.11
• • • • •
location and layout of the blast area access to the blast area description of the proposed blast permits/licences required details of adjacent structures/services.
How are risks assessed and controlled? A thorough, documented risk assessment is necessary to ensure the risks have been reduced using existing risk controls (see table over page for examples) or new or additional control measures have to be devised and implemented.
What are the specific requirements for the site? Each site will have different requirements such as level of personnel required. In most cases, the following people, with the appropriate level of competence and experience, have responsibility for planning, preparation and conduct of aspects of the blast: • shot firer (author of the BMP) • person responsible for the blast, including safety and security (usually the shot firer) • person giving approval to use explosives on site • other key people (eg site supervisor). The shot firer must hold a current WorkSafe Victoria licence authorising a person to use blasting explosives. For licensing information, go to the licensing webpage on the WorkSafe Victoria website worksafe.vic.gov.au Blasting on construction sites requires preparation of a safe work method statement to identify risks and describe risk controls measures, if there is a risk to health and safety. Other information specific for the site will relate to the location of the site (eg how close the blast is to any structures, services, public areas and other work areas) and what changes may be needed to ensure there is no danger to the public or risk of damage to structures or the environment. If blasting is for demolition of buildings and other structures, those conducting the blasting must notify WorkSafe Victoria in writing 21 days before the demolition. The notification has to include the demolition plan which details all relevant information specified in Appendix K of AS 2187.2
1
Guidance Note Blast management plans
Table 1 - Common risks and risk control measures to consider for a blast management plan Identified risk
Risk controls
Unauthorised access to blast area
• Security arrangements in place, such as access to authorised persons only and secured area with guarded gate.
Unauthorised access to explosives • Secure stores store/portable magazine • Security arrangement to prevent unauthorised access. Inadequate training and competency for staff
• • • •
Ensure shot firers are licensed. Train personnel in explosives products and blast design. Use tools to test blast eg model blast pattern technology tool. Develop and implement procedures to check training and competency.
Competency of contractors
• Review competency and training. • Set minimum standards. • State requirements in contracts.
Blasting procedure
• Develop and maintain safe blasting procedures. • Involve competent people in development.
Inconsistency in performance of explosives
• • • •
Use reliable supplier. Test explosives. Develop procedures for use of explosives. Ensure shot firers are licensed and experienced.
Unreliable firing methods
• • • •
Use reliable products. Test safety fuses, if used, and other equipment. Ensure equipment is maintained by competent people. Develop procedures for checking firing method.
Hot ground causing premature firing
• Use appropriate firing method and types of explosives. • Test in hot conditions. • Check ground before designing the blast.
Damage to structures
• Evaluate the affect of ground vibration and air blast overpressure on structures or ground conditions. • Revise blasting procedure to minimise damage.
Risk of fly rock
• Calculate quantity of explosives, stemming and capping. • Set up exclusion zones. • Use blast mats.
How will the blast be prepared and fired safely?
• details of reports, drawings and records consulted • post blast assessment and inspection procedures.
The BMP needs to describe the design of the blast necessary for the task and what procedures will ensure the charge is prepared and fired safely. This information includes: • layout of the blast including the drilling pattern and hole depth • drilling procedure • explosives type/quantity, firing equipment and method • procedures for loading and charging • detonation sequence/effective charge mass per delay (MIC) ‘powder factor’ • misfire procedure
What security is required? Security arrangements are necessary to meet the requirement in the BMP to ensure safety of workers, the public near the site and surrounding properties if in a built-up area. Arrangements will need to prevent unauthorised people entering the site and gaining access to the explosives to be used in the blast. The site should remain secure until the shot firer is satisfied the area is safe after the blast.
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Guidance Note Blast management plans
Other security matters to consider include: • setting up the exclusion zone • the communications system required for those involved in the blast • a plan to manage traffic around the site • information for owners/occupiers of structures, providers of services and neighbours • warning systems eg sirens • explosive storage and handling procedures.
Record keeping The results of each blast should be recorded and kept. This information assists in the planning and implementation of further blasts and provides documentation in case of incident or complaint. Records should include: • if tunnel blasting, presence of any hazardous atmospheres and inrush • environmental conditions at the time of the blast (eg rain) • measurements from the blast equipment and/or monitoring equipment (eg vibration and noise) • details of fly rock or fly • incidents and complaints • results of the blast • proposed modification to the blast plan for future blasts.
Further information Contact the WorkSafe Victoria Advisory Service on 1800 136 089 or go to worksafe.vic.gov.au More information • AS 2187.2: Explosives – Storage and use. Part 2: Use of explosives and Appendix K – Demolition of structures • Resources Safety (WA) guide, Guide to blast plan preparation, including mining operations • WorkSafe Victoria Guidance Note: Safe distances when using blasting explosives.
Note: This guidance material has been prepared using the best information available to the Victorian WorkCover Authority and should be used for general use only. Any information about legislative obligations or responsibilities included in this material is only applicable to the circumstances described in the material. You should always check the legislation referred to in this material and make your own judgement about what action you may need to take to ensure you have complied with the law. Accordingly, the Victorian WorkCover Authority cannot be held responsible and extends no warranties as to the suitability of the information for your specific circumstances; or actions taken by third parties as a result of information contained in the guidance material. WorkSafe Victoria is a trading name of the Victorian WorkCover Authority.
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