As the ACT Work Safety inspectorate begins a three-week blitz on Tuesday, ACT Work Safety Commissioner Mark McCabe confirmed the ACT's serious accident rate would put it at the top of the country's most dangerous construction jurisdictions.

The ACT recorded 30.5 serious injury accidents - requiring a workers' compensation claim and a week or more off work - for every 1000 workers on the job in 2011-12.

This is up from 24.5 the year before, which compared with a national average of 18.7.

When the accident rate is converted to a rate of actual injuries, 363 construction workers were seriously injured in the territory in 2011-12 compared with 321 the year before.

The new figures are due to be published by Safe Work Australia in their ''Comparative Performance Monitoring Report'' in October, which provides the most comprehensive industry by industry workers' compensation claim comparisons across the states and territories.

As the report has not been published yet, the ACT figures are not able to be compared with the other states or territories.

Tasmania had been slightly ahead of the ACT in 2010-11 for injuries requiring a week or more off work, but Mr McCabe said he could not imagine the ACT would not eclipse Tasmania with a 17 per cent increase.

When accidents requiring 12 weeks or more off work are tallied, the ACT already leads the nation with 9.5 accidents for every 1000 workers in 2010-11. This is well above Tasmania, on 5.6 accidents, with the national average 5.2.

While the ACT's construction workforce has remained fatality-free for the past 12 months, just last month Mr McCabe warned of a spate of serious accidents including two worksites being shut down over dangerous scaffolding and one investigation into a metal pipe being dropped from a scaffold that pierced an electric cable and narrowly missed a gas pipe.

Tuesday will see a blitz targeting residential construction across Canberra with inspectors issuing new on-the-spot fines of up to $3600. Inspectors will look at falls from heights, signage, fencing, amenities, housekeeping, scaffolding, electrical test and tagging, white cards and personal protective equipment.

The latest statistics showing the spike in serious accidents coincided with a horror year for Canberra construction, with four workers killed on the job - sparking an independent ACT government inquiry ''Getting Home Safely''.

''What this shows is that the surge in health and safety issues in the construction industry in 2011-12 was not just evidenced by the four fatalities in the ACT, but also by a steep rise in the rate of serious injury claims,'' Mr McCabe said.

Because the statistics are a year behind, Mr McCabe said the ACT would need to wait until October next year to see whether any of the reforms brought about by the government's acceptance of all 28 recommendations of the ''Getting Home Safely'' report would have a positive effect.

This includes the biggest single budget allocation for the Work Safety inspectorate of $5.7 million over four years to hire 12 new safety inspectors.

''This was never going to be a quick fix,'' Mr McCabe said.

Construction, Forestry, Mining and Energy Union ACT secretary Dean Hall said the statistics were bad last year but also showed the ACT ''has been the leading jurisdiction for serious injuries for some time now''.

''In the past five years only one territory has had a rate above 30 and that's the ACT,'' he said.

He also questioned how the ACT could surpass Tasmania's accident rate given ''Tasmania is a state which has serious heavy industry such as logging and mining. Canberra has the best-educated and wealthiest population in Australia but obviously doesn't care as much when it is workers who are getting injured.'' The Master Builders Association said: ''Regrettably, the data for the ACT has not been flattering over a number of years.''

Chief executive John Miller said: ''The first test will be what is seen in October next year for 2012-13 and then more so for 2013-14 when we should get the full impact of recent changes.''

While the MBA did contend that some ''bad data is attributable to a very accommodating Workers Compensation Scheme, the ACT long being regarded as a very easy target compared to other jurisdictions,'' it did recognise improvement was needed.