Australia's 457 visa programme is on track to record its strongest year since the global financial crisis, with an increase in demand for trade workers, according to officials.

Trades people have helped the 457 visa programme exceed the 2009/10 total with months to spare. Primary visa grants are 37% higher than at the same time last year, the latest figures show.

In April 2011, there were 4,200 applications for primary 457 visas, pushing the total to 42,872 for the year so far with already about 4,000 higher than the total number for 2009/10.

A spokesman for the Department of Immigration and Citizenship (DIAC) said this result shows the 457 visa programme is providing an important avenue for employers, particularly in the construction and mining sectors, to hire workers when local labour is not available.

'The increase can be attributed to an improved economic environment and increasing employer demand for overseas workers to fill skills vacancies. There have also been upward monthly trends in application rates, strong year on year growth in the grant rate, strong jobs growth as shown by the ANZ Job Index and continued low unemployment,' the spokesman said.

The programme is regarded as a temporary solution when local skilled labour is in short supply, allowing employers to hire overseas workers for up to four years.

'The number of trade workers and technicians coming to Australia under the 457 programme is up about 70% compared with the same period last year. In this programme year to April, there were 4,731 visas approved for construction workers and 2,777 visas approved for mining workers, which represents an increase of 79% and 43% respectively,' the spokesman added.

All trade workers and technicians must demonstrate they are skilled and experienced in their occupation and meet English language requirements to qualify for the visa. The English language requirement was raised in September 2009 and now aligns with the permanent employer sponsored scheme.

Processing times for 457 visas are also 30% lower than five years ago, with a median processing time of 22 calendar days. As part of the Budget, the government announced new funding for a 457 processing centre in Brisbane, which will aim to halve 457 visa processing times.

'The 457 visa program is uncapped, demand driven and highly responsive to the economic cycle. The programme's ability to respond quickly to emerging skills shortages is demonstrated by the total visa application rates, which track very closely to the ANZ Job Index. When unemployment goes down, demand for 457 visas goes up,' the spokesman explained.

'More than 18,500 organisations currently employ overseas workers, with about 70% of workers being employed in small and medium sized businesses,' he added.