Volume 10, Number 3—March 2004
Research
Legionella Infection Risk from Domestic Hot Water
Paola Borella*
, M. Teresa Montagna†, Vincenzo Romano-Spica‡§, Serena Stampi¶, Giovanna Stancanelli#, Maria Triassi**, Rachele Neglia*, Isabella Marchesi*, Guglielmina Fantuzzi*, Daniela Tatò†, Christian Napoli†, Gianluigi Quaranta‡, Patrizia Laurenti‡, Erica Leoni¶, Giovanna De Luca§, Cristina Ossi#, Matteo Moro#, and Gabriella Ribera D’Alcalà**
, M. Teresa Montagna†, Vincenzo Romano-Spica‡§, Serena Stampi¶, Giovanna Stancanelli#, Maria Triassi**, Rachele Neglia*, Isabella Marchesi*, Guglielmina Fantuzzi*, Daniela Tatò†, Christian Napoli†, Gianluigi Quaranta‡, Patrizia Laurenti‡, Erica Leoni¶, Giovanna De Luca§, Cristina Ossi#, Matteo Moro#, and Gabriella Ribera D’Alcalà**Table 1
Characteristics of water supply and distribution systems in the examined buildings (N = 146)
| Characteristic | Frequency no. (%) |
|---|---|
| Type of water |
|
| Groundwater |
67 (46.2) |
| Mixture water |
79 (53.8) |
| Disinfection |
|
| Cl dioxide |
58 (39.7) |
| Na hypochlorite |
30 (20.6) |
| Cl dioxide + Na hypochlorite |
32 (22.2) |
| None |
26 (17.5) |
| Plumbing material |
|
| Metal |
131 (89.7) |
| Plastic |
15 (10.3) |
| Type of heater |
|
| Independent |
|
| Gas, tank |
30 (20.5) |
| Electric |
22 (15.1) |
| Gas, instant |
55 (37.7) |
| Central |
|
| House |
36 (24.7) |
| Neighborhood |
3 (2.1) |
| Softening system |
|
| Absent |
124 (84.9) |
| Present |
22 (15.1) |
| Hot water circulation |
|
| Absent |
117 (80.1) |
| Present |
29 (19.9) |
| Plant maintenance |
|
| Never/every 2 years |
26 (17.8) |
| Once/year |
100 (68.5) |
| Every 6 months | 20 (13.7) |
