Controlled blasting explained

Safety first, every step of the way

Controlled blasting is a technique that is measured, monitored and analysed every step of the way to ensure it is conducted to the highest safety standards.

Explore the exact process, safety measures, and previous examples of the technique used successfully.

What happens before and after a blast?

The blasting sequence

How is dust managed?

Dust generation is reduced by multiple blast protection covers laid over the shaft before each blast. Blast mats are placed over the blast site to contain dust.

Blasted or spoil material from the controlled blast is tightly covered and removed by spoil trucks with minimal impact on air quality. 

See below to learn more about blast buffers.

How are
explosives managed?

A specially designed Explosives Transport Vehicle (ETV) is used for the safe transportation of inert explosives to the site.

The blast cycle

This excavation methodology will be repeated as a cycle until the shaft depth is reached for tunnelling to begin. While some rock breaking is involved in removing the softer top composition and levelling the shaft walls, 85% of the excavation is done by controlled blasting.

  • Drill down to reach blast distance and load explosives
  • Load buffer layers and blast mats
  • Blast access shaft
  • Excavate blasted shaft to remove material and trim walls (rock breaking)
  • Shotcrete walls for support and insert rockbolts where required
blast cycle

How is dust being managed?

Protection measures will be implemented to reduce dust. These multi-level covers will prevent flyrock and dust, as well as decrease noise, overpressure and vibration from the site spreading to the local community.
blast cover
Up to two metres of deep buffering material is placed on top of the blast lift. 'Blast mats’ made of thick, shock absorbing rubber are placed on the buffering material. Finally, a steel blast cover will close off the top of the shaft.

Controlled blasting is tried and tested

Controlled blasting in the urban environment is not new. Below is a list of projects that have successfully carried out controlled blasting under similar circumstances.
clem jones tunnel

Brisbane’s Clem Jones Tunnel

Opened: March 2010

Banora Point, Pacific Highway Upgrade

Banora Point, Pacific Highway Upgrade

Opened: September 2012

Tintenbar to Ewingsdale, Pacific Highway Upgrade

Tintenbar to Ewingsdale, Pacific Highway Upgrade

Expected completion: End of 2015

Get answers to some frequently asked questions.

next: get answers to faqs
  • Australian Governement - Building our future
  • NSW Now - The new state of business
  • Transurban
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Translation information

If you need an interpreter, please call the Translating and Interpreting Service (TIS National) on 131 450 and ask them to telephone the Community Information line on 1800 997 057. Our business hours are 9am to 5pm Monday to Friday.


إذا كنت بحاجة إلى مترجم ، يرجى الاتصال على دائرة الترجمة التحريرية والترجمة الشفوية (TIS National) في 131 450 منهم الى الهاتف Community Information Line على 1800 997 057. ساعات العمل من 9 صباحا إلى 5 مساءا من الاثنين إلى الجمعة.


若你需要口譯員, 請致電 131 450 翻譯和口譯服務 (TIS National), 要求他們致電 1800 997 057的 Community Information Line 我們的工作時間是 9am – 5pm


如果你需要口译, 请致电 131 450 联系翻译和口译服务要 (TIS National), 要求他们致 1800 997 057联系Community Information Line。 我们的工作时间是 9am – 5pm


통역시필요하시번역통역서비스 (TIS National) 에131 450 전화 하 고 들에게1800 997 057전화를Community Information Line에 전화하도록 요청하십시오. 업무 시간은 9am 에서 5pm 까지 월요일부터 금요일까지 있습니다.


Nếu cần thông ngôn viên, xin quý vị gọi cho Dịch Vụ Thông Phiên Dịch (TIS Toàn Quốc) qua số 131 450 và nhờ họ gọi cho Community Information Line qua số 1800 997 057. Giờ làm việc của chúng tôi là 9am – 5pm.

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