EFNARC Certification in Australian Specifications
EFNARC is the European federation whose sprayed concrete guidelines sit behind the Australian, European and American standards families as the industry's sprayed concrete reference. It also runs the industry's own nozzle operator certification scheme, the only globally recognised certification scheme that covers both Hand Spraying and Robotic Spraying of sprayed concrete. It is the certification all Australian clients ask for in tunnelling and mining.
What the Guidelines Give
Where the local standards have no dedicated clause, the figures the trade works to come from EFNARC. The nozzle distance of 1 to 2 m from a rig. The pass thickness starting points of 50 to 100 mm overhead and 100 mm on a wall. The accelerator dose worked on the total binder, with the worked case showing about 15 per cent less accelerator when the dose is left on the cement alone after part of the cement is replaced. The 600 x 600 mm square test panel and the energy absorption classes of 500, 700 and 1,000 J at 25 mm of deflection. The 50 mm core, drilled 7 days after spraying. Test panels not moved within 18 hours and at the laboratory within 48. A coefficient of variation target under 15 per cent across a panel set. And the effect of temperature: a 10 degree C change makes the accelerator reaction with the cement 2 to 3 times slower or faster.
On an Australian job the Australian standards are the main reference, then the European and ASTM standards, with EFNARC behind them. The project specification governs every time.
The Certification Scheme
EFNARC certifies nozzle operators in 2 separate categories, Robotic Spraying and Hand Spraying, because they are different competencies. The hand spraying scheme is new, and its certificate is the only hand spraying nozzle operator certification available in Australia. Both run through classroom theory, the EFNARC online examination, the VR simulator, 40 verified days of spraying recorded on the EFNARC work experience form, and a practical assessment with a Certified EFNARC Examiner present. The examiner observes, scores the panels, makes the recommendation and provides EFNARC with the evidence. EFNARC issues the certificate, and it is valid for 5 years.
What a Specification Is Asking For
Shotcrete quality cannot be inspected into a lining afterwards. Compaction, encapsulation of the steel, rebound kept out of the layer and thickness at the shoulders are all determined at the nozzle, pass by pass, and a core only shows one point. A specification that asks for EFNARC certified nozzle operators is asking for evidence that the person at the nozzle has done the theory, the verified days and an assessment with a record behind it.
A certificate in one category does not cover the other. A crew mobilised with Hand Spraying certificates for a robotic job is kept off the rig until the operators are certified in the Robotic category. An expired certificate is not valid, and the certificate does not replace the site's own induction, authorisation and verification of competency on the plant.
Our EFNARC Courses
Our director and founder, Scott Graham, is currently the only EFNARC Examiner in Australia certified for both the Robotic scheme and the new hand spraying scheme, and he holds the EFNARC nozzle operator certificates for both as well. We deliver both courses in Australia, on site or at other locations by arrangement. We trained and assessed 13 nozzlemen for EFNARC certification on the Coffs Harbour bypass tunnels, and we run VOC (verifications of competency) for hand spray, robotic spray and the plant your crew operates.
We run EFNARC nozzle operator courses for Robotic and Hand Spraying, on your site or at other locations by arrangement. The course pages have the modules and the enquiry form.
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