It takes several months for Transport Malta to process emission alerts sent by motorists through SMS, and more months for the vehicles to be tested, a report by the Auditor General shows.

It says that the number of SMS reports received from the public dropped by 74% between 2008 and 2011.

'Although Transport Malta is identifying those vehicles which have reached the SMS report threshold (three reports within three months) it is processing the mobile phone text messages at fixed intervals every quarter. By not processing SMS reports as least on a monthly basis, TM would have forfeited the opportunity to take the appropriate action at the earliest opportunity on those vehicles which have reached the report threshold. Consequently, a maximum delay of two months results when a vehicle reaches its reports threshold before TM's processing date."

The auditor said that Transport Malta contended that such processing times were not reducing the effectiveness of the Emission Alert Campaign since, ultimately, potentially non-compliant vehicles were summoned for emissions testing. Still the authority said it will continue to identify areas for potential improvement.

The auditor noted that "further processing time of around four months' is taken for the summoning of vehicles for a test.

Matters were further complicated since a substantial number of owners did not take their cars for the tests.

In 2011, there were 274 no shows involving 160 vehicles out of a total of 252 vehicles which were called for the test.

Of the 252 vehicles summoned for an emissions test during 2011, a random sample of 60 out of the 160 vehicles that did not show up following receipt of one or more test notices showed that a restriction on the vehicles' annual circulation licence was imposed in 79% of the cases after the second consecutive 'no show'.

Transport Malta said it will be ensuring that procedures are consistently applied, the auditor said.