Legionella

2011-12-19 | Automatomatic Sets

Effective protection against the development of legionella bacteria

Regulation of the Minister of Health of 29 March 2007, “the quality of water intended for human consumption FOR IN humans” (Journal of Laws of 2007. No. 61, item. 417). This regulation specifies the requirements for, inter alia, of the sampling of hot water in order to detect Legionella bacteria, the minimum frequency of sampling and procedures depending on the results of bacteriological tests. Study the occurrence of legionella bacteria in the hot water in buildings collective residential and healthcare facilities closed should be carried out from 1 January 2008. Changes in regulations to the requirements of the European Union, where the controls and safeguards of water, or air-conditioning, also against Legionella, it is for the owners or building managers duty.

Introduction to the issue.

Secure the front of legionella public buildings such as. Hospitals, dormitories, hotels, swimming pools, schools and residential complexes, which are often supplied with thermal energy by local boiler houses, it involves the use nowatorkiego solution which is hot tap water heater Z-BIS.
The problem of the demand for hot water usually is solved in a way that is not fully satisfactory, uneconomical and does not meet sanitary requirements. These boilers provide for these objects preparation of hot tap water, equipped with a capacitive, usually vertical heaters, sometimes with large capacities. A drawback of this solution may be uneven distribution of temperature stratification and heated water. In the lower and central part of such a heater temperature is sometimes the order of + 35 ° C to 40 ° C, which favors bacterial growth, especially legionella pneumophila strains. Less introduced in the issues discussed should be clarified that Legionella bacteria are the cause of the collapse of many people as a dangerous disease called Legionella, which is hardly curable and repeatedly entails death.

These bacteria grow particularly strongly in poorly designed systems of public buildings. This is a problem not only national, but global. One of the basic principles customize the installation of hot water for action to reduce the risk of legionella infection, is stored in the Regulation of the Minister of Infrastructure of 12.04.2004r. on the technical conditions to be met by buildings and their location (Dz.U.Nr 75/02). Regulation §120 section 2 reads: “Warm water system should ensure that you get at the point, the water temperature no lower than 55 ° C and not higher than 60 ° C and allow its periodic increase to not less than 70 ° C”.
It should be noted that the legionella bacteria at temperatures higher than + 60 ° C, not only did not multiply but die quickly. Preventing infectious hazards caused by the legionella bacteria requires compliance with certain rules of conduct both in the design and selection of equipment, as well as for their exploitation.
Talking and writing about hot water utility should first be noted that, in matters of its preparation clash two basic concepts. The first and older historically, referred to as “reservoir” is the fact that the water is heated and stored for a long time, while a substantial power consumption occurs the most during peak demand. The water supply is replenished on a regular basis, and limited demand outside of peak seasons, accommodated by systems of heat exchangers, storage tanks cooperating with this system.

The habit of many designers installation of heating and domestic hot water is sometimes so strong that they come up from the reserve to another, novel concept, which will be discussed further. It should be noted that until the mid-seventies of the last century was not discovered by the threat of occurrence of such hold-ups heated water pathogenic bacterial flora of the family “Legionella”, the universally accepted then the way, did not raise major objections or concerns.
Second, innovative concept to solve these problems, which takes the now increasingly common, is to give up some time to collect hot water. Replaces the preparation of hot water on a regular basis, as the present demand. This is ensured by the device as effectively and economically as in the above example of the former method, however, having the fundamental advantage that they are generally reliable and safe in terms of hygiene and health.

The innovative solution for hot water preparation.

Discussed below a device for preparing hot water, typically used in oil-fired boiler or gas, are innovative solutions used more widely. They are distinguished by small size, high efficiency, operational certainty and stability of the temperature of water prepared. Also, easy operation and favorable economic indicators. Most importantly – they eliminate the threat against the development of bacterial flora especially the “family of legionella.”

The wide range of products from the installation industry, produced by PPU “TERMEN” SA Wroclaw, specializing in heat engineering, were also mentioned, innovative device for preparing hot water Z “BIS”. All their series includes eight size and the subject of this discussion will just sacrifice them due attention. Note that these are the new generation of devices that meet the modern requirements of sanitary-hygienic, and are now increasingly being applied.

Compared to other known solutions used for this purpose, we considered a solution distinguished by specific features like:

effective protection against the development of bacterial flora especially family legionella,
the required heating water temperature 70 ° C,
providing a constant output temperature of 60 ° C and 55 ° C operating hot tap water without the need to increase the parameters of heating water to 90 ° C during peak hours
small size, and thus the low demand area several times greater efficiency as compared to traditional solutions tanks.
ensure adequate cooling water return heating below 57 ° C which guarantees good cooperation heater condensing boilers,
the high demand hot tap water considerably lower investment costs than when the use of many heaters capacitive-flow.
no need to use chlorine generators
It should be added that the heater TERMEN Z-BIS is designed for use with condensing boilers with high efficiency. This provides favorable cooling water heating to approx. 43 ° C. When this condition is met applicable for condensing boilers and gas oil, which is to keep the return temperature below + 57 ° C. Provision of such operating parameters of the known art capacitive-flow heaters coils was difficult.
They therefore did not meet the conditions for effectively condensing. The technical details of this solution are available on the water heater Z-BIS.
The basic features which distinguished the apparatus especially the wide range of performance, temperature stability heated water, simple operation and most importantly – protection against the development of a dangerous bacterial flora, especially bacteria of the Legionella family. The above advantages and technical supplies have been tested many times in practice operational.
To meet the needs of the market are produced, as mentioned in the eight-typo sizes with capacity from 70 to 780 kW and a nominal flow capacities of heating water from 1.7 m3 to 25.2 m3 per hour and the amount of water heated from 1200 to 13800 l / ho outlet temperature + 60 ° C. It meets fully the diverse needs of existing and potential users of these efficient and operationally safe equipment.
Existing approaches of using a capacitive heaters require higher flow temperature (up to + 90 ° C) to provide the desired temperature. Hot tap water in the peak cutting.
Also increase productivity by picking teams heaters proves to be uneconomical option. The proposed solution completely eliminates w / a nuisance. The comparison is shown in the table.

Usability these devices.

In addition to this discussion, it should be added that the issue here Heater Pans They are provided especially for use in such facilities where there is a periodic high demand for hot water. This applies, for example, large housing complexes, including such facilities as hospitals, dormitories, factories, hotels, barracks, schools, spas, swimming pool complexes and all objects where there is a periodic high demand for the supply of hot water.
The best recommendation usefulness and benefits of the use of these devices is to ensure high sanitary requirements, especially to eliminate the risk of legionella bacteria. Supported by the increasingly widespread use of heater Z-BIS, which is reflected in the growing interest in this innovative solution.
In conclusion it should be added that an important advantage of the heater Z-BIS are relatively small dimensions, so that the device does not occupy much space. They are: width 1300 mm, height 1800 mm, and a depth of 850 mm. This provides easy transport and installation at the destination. The practice so far fully confirms these advantages and speaks for an increasing use of these innovative devices to solve important problems of hygiene and thus protect our health.

Conclusions

The proposed hot tap water heater Z-BIS meets European guidelines designed to prevent against illness to legionellosis in systems producing hot tap water accordance with the guidelines of the European Parliament dok.2119 / 98 / EC.
Heater fully meet the technical requirements contained in the Regulation of the Minister of Infrastructure of 12.04.2002r. Dz. Law No. 75/2002, §118-§121.
The heater complies with the guidelines contained in the “Recommendations for the design of domestic hot water, ventilation and air conditioning systems to minimize proliferation of legionella bacteria.” Technical requirements COBRTI INSTAL – Issue 11.
It is a unique solution to the problem of health and economic security supply of hot tap water from the boiler room.