Versione italiana (quiz interattivo)
LEGIONELLA RISK ASSESSMENT
METHODOLOGY FOR ITALIAN FACILITIES
Technical guide to Legionella risk assessment in Italy: regulatory thresholds, risk factors, five-step methodology and answers to the most common questions from international compliance officers and facility managers.
What drives Legionella risk in your facility
The six principal risk factors assessed under the Italian State-Regions Agreement 2015 and WHO Water Safety Plan framework.
Facility type
Hotels, nursing homes, hospitals and industrial plants with cooling towers carry the highest baseline risk under Italian guidelines.
Water system age
Systems older than 20 years, or those not refurbished since original construction, are more likely to harbour biofilm and corrosion deposits that support Legionella growth.
Temperature management
The critical risk zone is 20–45 °C. Hot water stored below 60 °C and cold water above 20 °C significantly increases multiplication potential.
Dead legs and low-use outlets
Stagnant sections of pipework and infrequently used outlets (seasonal hotel rooms, rarely occupied wards) are prime colonisation sites.
Sampling history
Previous positive results (≥ 100 CFU/L in healthcare; ≥ 1,000 CFU/L elsewhere) significantly elevate the risk profile and trigger mandatory corrective action under Italian law.
Cooling towers
Evaporative cooling systems are the highest-risk installation category. They require dedicated risk assessment, regular disinfection, and biological monitoring at least twice a year.
When action is legally required
Action thresholds defined by the State-Regions Agreement 7 May 2015 (Rep. Atti 79/CSR) and ISS Guidelines 2024.
| Result (CFU/L) | Risk level | Required action |
|---|---|---|
| < 100 CFU/L | Low | No immediate action. Maintain routine monitoring schedule. |
| 100 – 999 CFU/L | Medium | Investigation: review water temperature, identify dead legs, check maintenance records. Preventive measures. |
| 1,000 – 9,999 CFU/L | High | Mandatory corrective disinfection (thermal shock or hyperchlorination). Notify competent authority if healthcare facility. |
| ≥ 10,000 CFU/L | Critical | Immediate suspension of water system use. Emergency disinfection. Mandatory authority notification. Facility closure if required. |
Healthcare facilities (hospitals, nursing homes) apply stricter thresholds: corrective action is generally required at ≥ 100 CFU/L in wards housing immunocompromised patients. Always verify with your local health authority (ASL/ASP).
Five steps to a compliant risk assessment
Aligned with the Italian State-Regions Agreement 2015, Legislative Decree 81/2008 and the WHO Water Safety Plan approach.
- 01
Identify facility type and water system age
Classify the facility (hotel, nursing home, condominium, gym, industrial plant) and record the year of construction or last major refurbishment of the hot and cold water distribution system.
- 02
Assess high-risk installations
Identify high-risk equipment: cooling towers, evaporative condensers, whirlpool baths, decorative fountains, dental units and any section of pipework not regularly used (dead legs).
- 03
Review temperature management and monitoring history
Verify that hot water storage is maintained at ≥ 60 °C, that cold water distribution remains below 20 °C and that the last accredited sampling was carried out within the period required by the applicable guideline.
- 04
Define corrective action thresholds
Apply Italian national action thresholds: investigative action at ≥ 100 CFU/L (healthcare); corrective action at ≥ 1,000 CFU/L; emergency measures at ≥ 10,000 CFU/L. Determine the appropriate disinfection strategy (superheating, hyperchlorination, copper-silver ionization).
- 05
Document and schedule periodic monitoring
Produce a written Water Safety Plan, set a periodic sampling calendar aligned with the State-Regions Agreement 2015 and store all chain-of-custody documentation for at least five years.
Italian self-screening quiz
INTERACTIVE 13-QUESTION QUIZ (IT)
The Italian edition of this page includes a free 13-question interactive quiz calibrated on the State-Regions Agreement 2015 and ISS Guidelines. It generates a personalised risk score (LOW / MEDIUM / HIGH / CRITICAL) and a downloadable PDF report with operational recommendations.
Questions on Legionella risk in Italy
Quick answers for compliance professionals, facility managers and international researchers.
What are the Italian Legionella action thresholds?
Under the State-Regions Agreement of 7 May 2015: < 100 CFU/L — no action required; 100–999 CFU/L — investigation and preventive measures; 1,000–9,999 CFU/L — corrective disinfection; ≥ 10,000 CFU/L — immediate closure and emergency disinfection. Healthcare facilities apply stricter limits.
How often must Legionella sampling be carried out?
Frequency depends on facility type and risk level. Hotels and healthcare facilities typically require at least one monitoring cycle per year; high-risk facilities (cooling towers, hospitals with immunocompromised patients) may require quarterly or more frequent sampling. The sampling plan must be documented in writing.
Does a risk assessment replace accredited laboratory sampling?
No. A risk assessment (written or tool-based) is a planning and prioritisation instrument. Regulatory compliance requires physical sampling by qualified field technicians and laboratory analysis by an ACCREDIA-accredited laboratory following UNI EN ISO 11731:2017.
Is a Legionella risk assessment legally required in Italy?
Yes. The State-Regions Agreement 2015 and Legislative Decree 81/2008 (Title X) require all operators of water systems in non-domestic settings — including hotels, offices, gyms and hospitals — to carry out a documented Legionella risk assessment as part of their overall health and safety obligations.
Can I use the Italian interactive quiz if I don't read Italian?
The 13-question self-screening quiz (available at /verifica-rischio-legionella) is currently available in Italian only. For international facilities or researchers needing an English-language assessment, please contact us directly.