Frequently asked questions:

Why must I filter and disinfect the water throughout the whole home?

Paying attention to the quality of your drinking water alone is not enough......during bathing and showering, volatile harmful chemicals are absorbed at roughly 1/3 inhalation, 1/2 orally and 1/3 skin absorption. This easily doubles and even triples your exposure to the harmful chemicals found in the warm water - children are even more at risk than adults.
For more comprehensive information here: HEALTHY WATER

The body needs 6-8 250ml glasses of HEALTHY water per day (tea, coffee, alcohol, juice and sodas DON'T count). Some of the problems treated and alleviated with adequate HEALTHY water intake are asthma, allergies, constipation, hypertension, high cholesterol, headaches, migraines, low back pain, rheumatoid arthritis, angina and cramp-like leg pain.

The PUREFLOW system does not remove the beneficial minerals from the water. For more information click here: WATER TEST SCAM

How often do I need to change the filters?

The life span of the filter cartridges cannot be pre-determined or guaranteed, as it depends entirely on the specific circumstances. The sediment filter stops the suspended dirt in the water, which to some degree protects the carbon filter from clogging, thus prolonging it's life span. Change the sediment filter when visibly dirty or when the water pressure drops.

Factors that will influence the change period:

• the water quality and quantity passing through the water filter system
• the age and material of the supply pipes - old municipal areas have galvanized pipes which rust with time
• if the supply pipes are worked on, mud and dirt will enter the supply network
• the amount of disinfectant (chlorine) added to the water supply

How do PUREFLOW Filters work?

Our filters work in stages to remove unwanted materials from water. The first stage, or pre-filter stage, removes suspended sediment, such as sand particles and dirt, from the water. The cartridge filter is made from spun-bonded polypropylene, which removes all suspended solids larger than 20µm in size.

The water then passes through an Activated Carbon filter, which further filters the water and removes organic, chlorine and chlorine compounds, herbicides, pesticides, phenols, turbidity, colour, bad taste and odour.

The filtered water then passes over an Ultra Violet light which neutralizes harmful bacteria and viruses to an efficiency of 99.99%

Our filters are extremely efficient. You will be astounded when you see what they remove from supposedly "treated" water that you buy from the municipality.

Using a PUREFLOW purifying system ensures that the muck you see in the "AFTER" picture on the right does not get into your body.

Our water filters remove the impurities so your liver and kidneys don't have to.

What is Ultra Violet (UV) disinfection and how does it work?

Ultra violet light is found between X-rays and visible rays on the electro magnetic spectrum. Falling between 200 and 400nm the ultra violet band is divided into 3 sub-bands, which are determined by the major effect characteristics of the radiation of these wavelengths.
These sub-bands are UV-A, having the longest wavelengths, and UV-B and UV-C, which have the shortest wavelengths.

Microorganisms contain nucleic acids, deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) which store all the genetic data. To survive and reproduce, the cell must be able to replicate the biochemical information in the nucleic acids exactly.

The radiation on the UV-C and the lower UV-B sub-bands show the highest absorption rates by the nucleic acids contained in microorganisms.

The maximum absorption of UV-light by the nucleic acids occurs between 260 and 265nm. It is this characteristic that gives the UV-C band its germicidal properties.

The emitted UV-light first penetrates the cell wall and is then absorbed by the nucleic acids in the micro-organisms. The absorbed energy then breaks down the links between their bases and rearranges their genetic information. This damage prevents the cell from reproducing and results in its death.

Mercury vapour lamps emit artificial UV-light.

PUREFLOW UV-reactors utilize low-pressure monochromatic lamps that emit light of 253,7nm wavelength, which falls closest to the 260/265nm maximum absorption rate.

The efficiency of a germicidal UV-system (UV-dose) depends on two factors, the intensity and the exposure time:

INTENSITY (W/m2): The intensity is simply the output power of the UV-lamp measured in Watt, per unit surface area measured in square meter. For standard low-pressure mercury vapour lamps, UV-intensity drops to below 85% of it's initial output after about 8000 hours of continuous operation and the lamp must then be replaced, as reliable disinfection can no longer be guaranteed.
PUREFLOW UV-reactors are equipped with fully electronic lamp drivers, which ensure the useful lamp life to at least 8000 hours and considerably increase the UV-intensity.

TIME (s): The residence time, measured in seconds, that the microorganisms spend in the reactor can be described as the time taken for the microorganisms to travel from the inlet-end of the reactor to the outlet. This is calculated from the velocity of the water and the physical design of the reactor.

UV DOSE (J/m2 ): These parameters are combined to give the UV dose, measured in Joule per square meter, the standard indicator of UV effectiveness. In its simplest terms, UV dose is a function of intensity and time and reads as follows: UV dose = UV intensity x Time ie, (J/m2) = (W/m2) x (s)

The Germicidal Efficiency of PUREFLOW UV-Reactors The Petri dish samples on the left show extensive bacteria colony development in the culture medium before UV, whereas no infection is to be detected in the "after" samples	The Physical Efficiency ofPUREFLOW UV-Reactors The photographs on the left show hard minerals typically found in water, which attach themselves to pipes and appliances to form scale. The "after" samples show the conditioned crystals, which have been magnetically charged.  The minerals can not attach themselves to form scale
The water produced complies with all bacteriological standards set for drinking water.	The water produced complies with all bacteriological standards set for drinking water.

What factors have to be considered when designing a UV system?

FLOW AND TURBULENCE

Before any system can be designed it is vital to ascertain the amount of water that is to be treated and irradiated on within a certain time frame. This defines the flow rate, expressed in litres per hour (l/h) or in cubic meters per hour (m³/h) for higher flow rates. This flow rate must be determined for the actual peak demand, which means the highest possible litres per hour to be radiated during any 24-hour period.
To ensure that all microorganisms receive the correct UV intensity for the necessary length of time and thus reliable disinfection taking place, the turbulence within the reactor must be optimized. This will prevent the microorganisms from short circuiting the required flow path. It is therefore crucial that the correct dimensions and hydraulic characteristics are incorporated into the reactor at design stage, otherwise optimum turbulence may not be achieved at minimum demand levels.

TYPE AND CONCENTRATION OF MICROORGANISMS

A bacteriological examination of the water to be treated must be performed to detect sewage pollution of the water. As a general rule, water contains many types of relatively harmless saprophytes, which normally inhabit the soil, air and water. However, both ground and surface water may be contaminated by domestic sewage, which may contain human pathogens, such as Typhoid, Dysentery, Hepatitis, Diarrhea and Cholera. These viruses or bacteria are considered to be of faecal origin.

Contrary to common belief, no examinations are made to detect specific pathogenic microorganisms. The routine bacteriological analysis is based on the approximate determination of the total numbers of organisms present, plus the presence or absence of the more common organisms of intestinal or sewage origin.
The most common are the bacteria of the coliform group and they are therefore singled out to serve as index organisms of faecal pollution. The prevalent species are the various strains of Escherichia coli, followed by Enterobacter aerogenes.

The advantage of testing for these organisms rather than for specific pathogens is that the coliform organisms are constantly present in both healthy and diseased humans in large numbers, billions are excreted daily by the average person.

It is estimated that for every Typhoid bacillus or other pathogens e.g. viruses of Polio or Hepatitis in polluted water supplies, there are usually millions of  coliform organisms, especially E. coli. Another advantage is that the coliform group survives for longer in an aquatic environment than do most other intestinal pathogens.

In addition, the presence of these organisms is easily detected using a relatively quick method, in contrast to the more tedious, time consuming identification of a specific pathogen. For complete termination, different pathogens need specific UV doses. In general, a determination is made of the UV dose required to terminate E. coli. This is the basis for all other system-design calculations.

LEVEL OF DISINFECTION REQUIRED

All applications will not require complete disinfection. In some instances partial reduction may be adequate i.e. when treating certain types of process, irrigation or closed recycling water systems.

INFLUENCE OF WATER TEMPERATURE

For low-pressure lamp systems the temperature of the water to be treated should fall into the range of 5°C to 30°C with optimum efficiency at 19°C.

TRANSMISSION POTENTIAL OF WATER (Transmissivity)

The ultimate amount of UV light that will pass through a volume of water depends on several factors, which relate to the physical properties of both the UV radiation and the water.

Factors that lower the transmissivity of water:
SUSPENDED SOLIDS

They effect UV transmission by blocking, scattering and absorbing UV light and may also shield or carry within them some microorganisms, which need to be treated. Suspended solids increase the number of surviving microorganisms.
Therefore they have to be limited by filtration, coagulating or settling prior to the UV disinfection of the water.
EXAMPLE:

COLOUR

The discolouration of water is in most instances caused by the presence of minute particles of organic matter. Surface water usually contains complex organic molecules known as Humic and Fluvic acids, which shows as a brownish discolouration. These molecules absorb UV light. Measuring devices available read the rate of absorption of visible light, meaning that water that appears very clear might still have a high UV light absorption potential.
Organic matter should be limited by activated Carbon filtration.

TURBIDITY

Due to the suspension of finely divided matter, turbidity can be seen as a lack of clarity or brilliance in water. Turbidity is the measure of light transmission through a sample. It must not be confused with colour, since water might have a dark colour but still be clear and not turbid. Clay, silt, fine organic and inorganic matter as well as microscopic organisms may all cause turbidity. Although closely related with suspended solids, which is the absolute quantity of matter in a sample, turbidity is not equivalent to the amount of suspended matter. If necessary, it might be limited by activated Carbon or ultra filtration.

What are the advantages of using UV for the disinfection of water?

• The chemical and physical properties of the treated water remain unchanged
• No toxic compounds or their precursors are introduced
• The entire process is environmentally friendly
• The operation is highly economical
• Installation and operation is simple, there is no need for skilled or specialized personnel

What is your Warranty Policy

• All material and workmanship of our products is guaranteed when installed and operated according to our specifications
• Any parts proved defective within a period of one year from date of purchase, will either be repaired or replaced at our sole discretion, provided that the defective part/s are returned to our premises
• On-site inspections and service may be requested and will be charged for at the ruling tariff for traveling and labour at the time of request
• The life span of the filter cartridges cannot be pre-determined or guaranteed, as it depends entirely on the specific operating conditions