The Department uses dongas to provide both prisoner accommodation and staff workplaces. Our results show they are inefficient at moderating temperature. Dongas are prefabricated transportable buildings used as stop gap measures to cope with prison population pressures. The Department’s use of dongas as accommodation for prisoners was initially intended to only be a temporary solution to the growing population, however, they have remained as permanent fixtures in several facilities.
The dongas used in metropolitan facilities had unacceptable temperature variation. Temperatures were measured in dongas in Karnet and Bandyup. They demonstrated widely variable temperatures that corroborated prisoner descriptions of them being exceptionally hot, uncomfortable, and akin to a sauna. The donga cells demonstrated substantially warmer temperatures than cells in an adjacent brick constructed building.
Temperature conditions in donga and brick constructed cells at Karnet Prison Farm
| Cell type | Avg. temperature (°C) | Avg. maximum temperature (°C) | Avg. temperature variation (°C) |
| Brick cells | 27.5 | 31.9 | 10.7 |
| Donga cells | 28.5 | 38.8 | 18.5 |
| Difference | +1.0 | +6.9 | +7.8 |
The donga accommodation at Karnet placed prisoners at an increased risk of heat-related illnesses:
- Temperatures within dongas were observed to be 6°C hotter than brick constructed cells in the middle of the day.
- Acceptable temperatures were attained in dongas 63 per cent of the time. Brick constructed cells attained acceptable temperatures 80 per cent of the time.
- Dongas attained an ‘extreme caution’ risk rating for one-third of the measurement period, with one donga attaining a ‘danger’ risk rating on some occasions. In comparison, brick constructed cells rarely attained an ‘extreme caution’ risk rating and never came close to attaining a ‘danger’ risk rating.
Ventilation windows and block out curtains have been retrofitted to the dongas in Karnet in an attempt to address the heat. Fly screens have also been installed in doorways. This has improved air flow which was previously inhibited by prisoners draping torn-up garbage bags across doorways to prevent flies from entering. While these small measures are commendable, the temperature readings show that they have not significantly improved conditions to acceptably reduce the risk of heat-related illness.