Dubai is the world’s fastest growing city, with a vision to create a world-class destination for residents, visitors and businesses alike. A key element in Dubai’s transformation is the construction of a series of iconic artificial islands, including the Palm Jumeirah, Palm Jebel Ali and Palm Deira developments. Designed to generate maximum beach frontage and dubbed the ‘Eighth Wonder of the World’, the islands are creating a large number of residential, leisure and entertainment areas.

The Palm Jumeirah Island is approximately 5 km long by 5 km wide and offers an outstanding array of retail and lifestyle options for residents and tourists to enjoy. The Crescent area features some 30 international hotels of the highest quality, with easy access to a number of fascinating scuba-diving sites nearby. At the head of the Crescent is the 40-acre ‘Atlantis’ water theme park that features an aquarium where guests can swim with dolphins.

Road access to the Palm’s Crescent from the ‘Trunk’ section is provided by the Palm Jumeirah Vehicular Tunnel, which forms the only link between the Trunk and the Crescent; the total length of the tunnel is approximately 1.4 km, including the approaches, with an underwater section of about 600 metres.

Halcrow provided advice on the selection of fire scenarios for the design of the tunnel using heat release rate cases of 30, 50 and 100 MW, based on projected traffic levels and a risk assessment methodology. A report was produced which described the implications of the various fire scenarios in terms of the required tunnel ventilation capacity and structural fire safety protection.

As a result of revised traffic level forecasts, the fire safety assessment was updated to highlight an increased probability of accidents and a credible worst case scenario that might result in the complete collapse of the structure.

Subsequently, a joint risk assessment workshop was convened to discuss the implications of these findings and the results of this exercise were:

	Definition of design fires for tunnel ventilation and structural fire protection
	Recommendation of passive fire protection for the tunnel structure