Legionella Prevention and Control

The bacteria Legionella naturally exists in aquatic environments such as rivers, ponds, streams and reservoirs. Among the dozens of known species, Legionella pneumophila is considered the most pathogenic for humans, as it can cause a respiratory infection known as Legionnaires’ Disease. The infection is transmitted through inhalation of droplets of contaminated water, and there is no contagion by ingestion or from person to person.

Hazardous locations
The development of Legionella in artificial water systems is more frequent in cooling systems, hot and cold water supply systems in buildings and climatized water systems. Legionella can also grow in water supply/distribution systems, fire fighting water systems, sprinkler irrigation systems, car washing, gas washing systems and ornamental fountains.

Risk factors
Legionella proliferation depends on several factors, such as water temperature, pH, relative humidity, existence of stagnant areas, existence of biofilm on surfaces in contact with water, existence of oxidized or porous surfaces in contact with water.

Effect of water temperature on the development of Legionella:

Manusystems is available to support you in the prevention and control of Legionella, providing the following services:

  • Establishment of the critical points of your installation;
  • Installation of systems for chemical or thermal disinfection of water;
  • Implementation of measures to prevent bacteria;
  • Disinfection of cold and hot water tanks;
  • Disinfection of cold and hot water distribution system;
  • Water sampling for analysis of Legionella by culture or PCR with accredited laboratory.

Manusystems provides the following products for Legionella prevention and control:

Chlorine or hydrogen peroxide based biocides
– For chemical disinfection of faucets/showers


– For diary control of temperature and during the thermal disinfection of system
– Range of measuring: -50 a 150ºC
– Resolution: 0,1ºC
– Precision: ± 0,3ºC
– Price: 45,00 € + IVA

Manusystems – Manutenção de Sistemas, Lda.
Phone number: + 351 262 836 480
Fax: + 351 262 836 481
VAT: PT 507 791 061


Zona Industrial de Caldas da Rainha
Rua Pedro Nunes, n.º 38, Armazéns R e S
2500-303 Caldas da Rainha

Phone number: + 351 262 836 480
Fax: + 351 262 836 481

Rua da Junqueira, n.º 23
4480-156 Azurara

Phone number: +351 252 143 763

Rua 26 de agosto, n.º 7A
2500-882 Caldas da Rainha