Ensuring The Safety of Climbers on Sydney Harbour Bridge

In October 1998 marked the commence of hosting guided climbs to the top of one of Australia’s most famous engineering icons, the Sydney Harbour Bridge. To date, over two million tourists and locals have made the climb with many claiming it as the most memorable thing to do in Sydney.

Naturally, safety is of paramount importance! As well as ensuring that there is no possibility of danger to climbers or those below, there are other factors that also need to be taken into account. Excessive heat can result in fatigue and potential heatstroke, while strong winds can be dangerous to climbing operations. To complicate things further, weather conditions 134 metres above sea level on top of the famous “coat hanger” can vary considerably from those on the ground. For this reason, accurate weather information from the top of the Bridge needs to be made available to the team in real-time at their operational headquarters.

In 2005, Campbell Scientific Australia was approached to provide a reliable, cost-effective solution for providing weather monitoring equipment, associated software, communication equipment and computer displays of the current weather conditions on top of the bridge. Our smallest data logger, a CR200 was selected for the role. An RM Young 05103 Wind Monitor measures wind speed & direction while a Vaisala HMP45C measures RH and air temperature. This equipment is installed at a point on top of the bridge known fondly as Blinky Bill, a small landing supporting an aircraft hazard warning light. The equipment runs from an AC power supply with battery backup. Data is transmitted to the operational headquarters at the base of the bridge using a pair of Trio 450MHz radios and a Yagi directional antenna.

Updated information is provided by radio every minute while weather information is automatically updated on a webpage every half-hour. The data is collected using Campbell Scientific’s Loggernet software. Data presentation is handled by RTMC, the graphical display module of Loggernet and presented in multiple different formats - for the climb operations & safety team, on monitors in the foyer and delivered to the web site.