For the 3 years up until early 2006 the RTA trialled school zone flashing lights at 43 schools across NSW. The results of the trial were published in April 2006 in a 110-page report that is available on the RTA's web site
The report describes a rigorous scientific study conducted in accordance with accepted data collection and statistical analysis procedures and standards.
The trial tested two main types of lights, Type 1 which were simply two flashing lights like mine, and Type 3 which consisted of two flashing lights plus flashing LEDs around the "40" numerals.
Speeds were measured before and after the lights were installed, as well as nine months later to check for any variations in the figures. Control sites without lights were used to validate the results.
Following exhaustive statistical analysis the report concluded (p. v and vi and p.65) that Type 1 lights reduced average traffic speeds by 50% more than Type 3 lights. The report further concluded (p.67) that the speed reductions achieved by flashing lights reduced the risk of fatal crashes around schools by 11%.
The report states repeatedly that the results are statistically significant (p.v, vi, vii, 46, 57, 64, 65, 67, 68).
In spite of the above the RTA subsequently adopted the less effective and far more expensive Type 3 lights for future installations, ignoring the results of 3 years' worth of research.