News - Week 6: Diving in contaminated water

Fig. 1 Mads is dressed in a Viking HDS suit and Andrzej sports a Viking Pro 1000

Fig. 2 Chryssanthi is diving in a Viking HDS suit and is wearing a AGA full face mask

Fig. 3 Eva decontaminates Mads

Author: Panagiotis Athanasopoulos and Vassilis Tsiairis

The sixth week is now complete at Zea. We have finished our work in Area 2 where we excavated four trenches with very interesting results. Early in the week we moved to Area 3, where there is new evidence that may indicate the presence of a wider shipshed type - perhaps accommodating the larger warship types (the so-called ‘fours’ and ‘fives’) introduced in the late 4th century BC.

We have stressed before that on the ZHP health and safety are of the utmost priority. One of the most important issues the project has to deal with is the potentially contaminated waters within the harbour basin. The harbour environment is our working environment, thus environmental changes greatly affect our work.

Zea (as well as the other two Piraean harbours Mounichia and Kantharos) is a modern and busy harbour with a closed basin in a highly populated area. As a result of the constant marine activity throughout the year and the density of the population around the harbour, organic and chemical waste occasionally enters the harbour’s waters. These contaminants are clearly visible as a thick layer on the seafloor in some parts of the harbour, and other contaminants such as diesel fuel float on the surface. Inevitably the concentration of this material fluctuates throughout the day and within different areas of the harbour. Therefore, in order to minimize the risks associated with the exposure to polluted water, we consider the sea water to be contaminated at all times.

To protect ourselves we use specialized equipment that prevents divers, as well as their tenders, from coming into contact with sea water. This is a very difficult task when working on an underwater project!! When working underwater, all archaeologists wear vulcanized rubber drysuits especially designed for exposure to contaminated water. We have mostly used the Viking Pro 1000 model, and a new addition to our equipment list is the Viking HDS drysuit, which is even more resistant to chemical and organic contaminants (Fig. 1). The suits we use have a dry hood onto which the AGA full face mask attaches. The AGA mask is designed to maintain a positive pressure in order to prevent any water from leaking inside the mask (Fig. 2). Divers and tenders also wear specialized dry gloves. All of these necessary protections aim to minimize our exposure to the contaminated environment.

Once the dive ends, the diver and the equipment are decontaminated and sprayed thoroughly with fresh water (Fig. 3). No diving equipment is removed from the diver unless it has been properly decontaminated. The strict implementation of this safety protocol during our working years in Piraeus has kept our staff healthy and our director happy!