Inspections BRL6010 Legionella

BRL 6010 Legionella


Over the last years, much attention has been paid to everything relating to Legionella, and rightly so.

Many existing systems, but also newly designed systems appear to host many risk factors which could result in the growth of Legionella. 

What is Legionella?

Currently, about 20 types of Legionella bacteria have been identified that are known to cause Legionnaires´ disease, otherwise known as Legionellosis. Legionella bacteria occur in surface water and, in very low concentrations, in drinking water. Additionally, the bacteria hav often been found in drinking water systems, hot water systems, cooling towers and hot tubs. Under the right conditions these bacteria can multiply in no time.

People can get infected from breathing in aerosols (very small water droplets) with Legionella bacteria. Legionellosis comes in two varieties:

  • Pontiac fever (resembling flu);
  • Legionnaires´ disease (Legionella-pneumonia, a serious type of pneumonia), which is potentially fatal if not treated in time.

Risk factors in hot and cold water systems

Risk factors for the multiplication of Legionella bacteria in wholesome mains supply systems are:

  • Water temperature, multiplication occurs at temperatures between 25º- 50ºC.
  • Staying time, if the water remains in the system for a long time, this may encourage bacteria to multiply.
  • Stagnance of water in the system over longer periods of time (days or weeks).
  • Biofilm (Biofilm is a layer of micro-organisms that produce a slime with which it attaches to a surface. The Legionella bacteria can lodge in this biofilm and subsequently spread over the entire system. It may also protect the Legionella bacteria against thermal decontamination, which is intended to eliminate the Legionella bacteria).  
  • Sediment (Sediment is a deposit of polutants in the water. Particularly in boilers and other storage tanks, sediment may collect on the bottom. The sediment is a source of nutrients for bacteria such as Legionella)  
  • Hotspots in water systems.

Drinking Water Act and Drinking Water Decree:

Since 1 July 2011, the new Drinking Water Act and Drinking Water Decree are in force, in which it is laid down that owners of collective mains supply systems in the priority risk category (previously high and middle category) have a legal obligation to carry out or have carried out a Legionella risk assessment on the basis of the ISSO 55.1 standard, and to draw up a control scheme or have such a scheme drawn up by a BRL 6010-certified company. In addition, the results of the control measures ensuing from the control scheme must be recorded in a log. 

Failure to comply with Legionella legislation is regarded as an economic offence (substantial fines).

Examples of systems in the priority risk category:

  • Hospitals;
  • Healthcare establishments;
  • Accommodation centres;
  • Asylum seekers´ centres;
  • Prisons;
  • Public baths, such as swimming pools and saunas;
  • Camping sites;
  • Marinas;
  • Truckstops, gas stations and roadside restaurants with public showers.

All remaining collective systems (no priority) fall in the low-risk category. For those systems the duty of care to “supply wholesome drinking water” applies, in accordance with the ISSO 55.2 standard.


Examples of systems in the non-priority category:

  • Offices and companies;
  • Educational institutions and other public buildings, government buildings;
  • Recreation such as: sports centres and sports fields, beaches, amusement parks and zoos;
  • Shopping centres and department stores;
  • Care residences;
  • Fire stations;
  • Industry.

Owners of non-priority collective systems need to be able to prove that the drinking water they supply is wholesome. In other words, the owner has to be able to prove that the drinking water he supplies does not constitute a risk to people´s health. The owner can prove that he complies with these requirements by having a risk inventory and control scheme drawn up in accordance with ISSO 55.2. If, in the event of a contamination, the system owner cannot prove that he has done all he could to prevent contamination, this could have far-reaching consequences. 

BRL6010 certification

Delmeco meets the official BRL 6010 certification requirements and is one of a small number of certified companies in Zeeland. Our Legionella experts can carry out a risk assessment and draw up a control scheme for you, so you will know whether you comply with the requirements of the Drinking Water Act. We will identify the sources of risk of the hot and cold water systems and point out flaws in the systems and the required adjustments or control measures. The control scheme states which periodical precautions need to be implemented and who is responsible for the implementation of control measures.

Additionally, you, as our customer, can rest assured that our new systems and adjustments to current systems meet the latest requirements in the field of Legionella prevention. 

The inspection is carried out following the steps below:

  • Initial meeting;
  • Offer;
  • Risk assessment: Your system will be inspected from water meter to tap. We pay particular attention to: hotspots, mains diameters, materials used, drinking water consumption pattern, redundant pipe work in the mains and environmental temperature;
  • Drawing up a report (documents + drawings);
  • Discussion of the report with customer.

We can also assist you in selecting the right partner for correcting any flaws found, building supervision and completion.


We have assisted various customers in Zeeland and the southwest of the Netherlands with the implementation of a Legionella control scheme.


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Delmeco Raadgevend Ingenieurs bureau

Marquesweg 4
4462 HD Goes, The Netherlands

+31 (0)113-270484