A Glossary of terms relating to the eBoosterTM and water treatment

Acceptable level of risk

The level of risk a facility is prepared to accept for a hazard and/or hazardous event. Risk levels range from low to very high. A facility should determine its acceptable level of risk for each identified hazard and/or hazardous event before performing a risk assessment.

Approved provider

An entity for which an approval is in force under the Aged Care Act 1997 (Commonwealth).

Backflow prevention device

A device used to prevent reverse flow within a water distribution system which could draw contaminated water back into the system.


A slimy three-dimensional structure made of organic materials (sugars, proteins, lipids, and cellular molecules) secreted by different microorganisms. A biofilm is a biological system that can metaphorically be described as “a city for microbes”; biofilm bacteria share nutrients and are sheltered from harmful factors in the environment, such as desiccation and chemical disinfectants.

BMS system

A building management system (BMS) is a computer-based control system that enables the control and monitoring of the mechanical and electrical equipment of a building such as ventilation, lighting, power systems, fire systems and security systems.


A bypass is a system of pipes and valves that allow divert the flow from a pipe section that is under repair or rehabilitation. This diversion allows the flow to continue when the primary line is blocked.


Comparison of measurement values delivered by a device under test with those of a calibration standard of known accuracy. Calibration may be required for the following reasons:

  • a new instrument
  • after an instrument has been repaired or modified
  • when a specified time period has elapsed
  • when a specified usage (operating hours) has elapsed
  • before and/or after a critical measurement
  • after an event, for example after an instrument has been exposed to a shock, vibration, or physical damage, which might potentially have compromised the integrity of its calibration
  • whenever observations appear questionable or instrument indications do not match the output of surrogate instruments
  • as specified by instrument manufacturer recommendation.
Chemical disinfectants

Antimicrobial agents applied to non-living objects to destroy microorganisms that are living on the objects. Disinfectants target and destroy the cell wall of microbes or interfere with their metabolism, but are not necessarily able to kill all microorganisms, such as resistant bacterial spores.


Derivatives of ammonia by substitution of one, two or three hydrogen atoms with chlorine atoms (monochloramine NH2Cl, dichloramine NHCl2, trichloramine or nitrogen trichloride NCl3) and all chlorinated derivatives of organic nitrogen compounds.

Chlorine dioxide

Chlorine dioxide is an exceptionally reactive gas, which is not stored due to its instability but rather needs to be manufactured to meet requirements at its place of use in special systems.

Chlorine dosing

Chlorine dosing is intended to establish a free chlorine residual in a water distribution system. A free chlorine residual is effective against most bacteria (including Legionella) but harmless to humans (when within guideline values).


A device used to measure the amount of chlorine in a solution.

Combined chlorine

The fraction of total chlorine present in the form of chloramines (mono-, di-, or tri- chloramine) and organic chloramines.

Control measure

An action/activity undertaken to reduce or prevent a hazard.

Control point

Location within a water distribution facility at which a hazard may be reduced or prevented (e.g. point-of-entry into a facility, water leaving a storage tank within the facility).

Critical limit

Maximum and/or minimum value set for a particular parameter, measured during monitoring (operational and verification) that indicates controls are effective.

Dead leg

Section within a water distribution system that does not allow the flow of water.

Disinfection residual

The level of disinfectant remaining in a water distribution system after the disinfectant has been dosed.

Distal outlets

Those outlets in a water distribution system located furthest from the water source. For a cold water system, the source could be the inlet to the facility and for a warm/hot water system the source could be the heater or the warm/hot water storage tank.

Dosing point

The location in the water distribution system where small amounts of chemical disinfectant are injected (sometimes at intervals).

Drinking water service provider

All councils or businesses involved in treating, storing, distributing, and reticulating water for drinking purposes. They must be registered under the Water Supply (Safety and Reliability) Act 2008 to provide the drinking water service and are subject to state government regulation.


An electrochemical device allows to either generate electrical energy from chemical reactions or to use electrical energy to cause chemical reactions.


Death or severe injury by electric shock, electric current passing through the body.


An electrode is an electrical conductor used to make contact with a non-metallic part of a circuit (e.g. a semiconductor, an electrolyte, a vacuum or air).


It is the passing of a direct electric current through an electrolyte producing otherwise non-spontaneous chemical reactions at the electrodes.


Also referred to as electropermeabilization, it is a microbiology technique in which an electrical field is applied to cells in order to increase the permeability of the cell membrane, allowing chemicals or drugs to be introduced into the cell.


Building(s) sharing plumbing connections under the control of the facility manager, even when not used for clinical purposes.

Flow restrictors

A device designed to limit the flow of water that comes out of a tap or other dispenser.

Free chlorine

Chlorine present in the form of hypochlorous acid (HOCl), hypochlorite ion (ClO) or dissolved elemental chlorine gas (Cl2).

Free chlorine residual

Concentration of residual chlorine in water that is present as dissolved gas (Cl2), hypochlorous acid (HOCl) and/or hypochlorite ions (ClO).


An agent (microbiological, chemical or physical) that has the potential to cause harm to patients/residents (e.g. Legionella pneumophila or water above 50°C).

Hazard source

A location or condition that can give rise to, or increase, a hazard (e.g. a dead leg in the plumbing which is a source for stagnant water and hazard proliferation, under suitable conditions).

Hazardous event

A situation that can lead to the presence of hazard or hazardous source (e.g. a decrease in temperature in a hot water system can provide conditions suitable for Legionella growth).

Heterotrophic colony count / Heterotrophic plate count

A method that measures colony formation, on culture media, of heterotrophic bacteria in water. This gives an indication of the total microbial load in a water supply, but does not indicate the safety or otherwise of the water.

Hot water heaters/system

A heated water system that delivers heated water through the majority of a water distribution system at a temperature equal to or greater than 60°C. May include thermostatic mixing valves.

Hydrogen peroxide

A reactive oxygen species with the formula H2O2 and the simplest peroxide, a compound having an oxygen–oxygen single bond. It decomposes slowly when exposed to light, and rapidly in the presence of organic or reactive compounds. It is typically stored with a stabilizer in a weakly acidic solution in a dark bottle to block light.

Hypochlorite (ClO−)

An anion with the chemical formula ClO; it combines with a number of cations to form hypochlorite salts. Common examples include sodium hypochlorite (household bleach) and calcium hypochlorite (a component of bleaching powder, swimming pool ‘chlorine’). Because of its negative charge, it is not able to penetrate pathogens’ membranes.

Hypochlorous acid (HOCI)

A weak acid that forms when chlorine dissolves in water, and itself partially dissociates, forming hypochlorite (ClO). HOCl and ClO are oxidizers, and the primary disinfection agents of chlorine solutions. Hypochlorous acid is found naturally in white blood cells of mammals, including the human body. HOCl is non-toxic and has been used as a safe wound care solution for many years. It has been identified as a disinfectant effective against COVID-19, backed by clinical studies. Because of its ability to penetrate pathogens’ membranes, it is also used as a commercial deodorizer.

Immune response

In response to infection, the human immune system generates minute quantities of hypochlorous acid within special white blood cells, called neutrophil granulocytes. These granulocytes engulf microorganisms (e.g. viruses or bacteria) in an intracellular vacuole called the phagosome, where they are digested.

Interruption to supply

Scheduled or unscheduled, temporary break in supply of drinking water to a facility.


Bacterium which causes Legionnaires’ disease, some species of which thrive in water distribution systems.


An illness caused by exposure to Legionella.


The average length of life of a material object, especially in a particular environment or under specified circumstances.

Mixer tap

A tap for controlling the flow of water enabling hot and cold water out of the same pipe. It ensures the flow of each is controlled separately so that the temperature of the water coming out can be adjusted.

OHS risks

Occupational Health and Safety (OHS) risks are those hazards that can lead to the harm, injury, death, or illness of a worker in a determined workplace.

OHS risks

Occupational Health and Safety (OHS) risks are those hazards that can lead to the harm, injury, death, or illness of a worker in a determined workplace.

Operational monitoring

Scheduled, real-time monitoring of specific parameters within a water distribution system to check the effectiveness of control measures (e.g. checking the temperature of the hot water system).


Chemical addition is a critical process in the provision of safe drinking water. This process step presents the very real and often underrated risk of chemical overdosing in the water supply system. Also the risks associated with underdosing are fairly self-evident: a failure to keep water quality within regulatory limits can lead to fines, operational mandates and irrevocable hits to the reputation of a water service providers.


An inorganic molecule with the chemical formula O3, formed from dioxygen (O2) by the action of ultraviolet (UV) light or electrical discharges. Ozone’s odour is reminiscent of chlorine, and detectable by many people at concentrations of as little as 0.1 ppm in air. It’s a powerful oxidant and has many industrial and consumer applications related to oxidation. Because of its high oxidizing potential, it damages mucous and respiratory tissues in animals and also tissues in plants, at concentrations above 0.1 ppm. It can be generated on site from oxygen, and introduced to the water directly, without interim storage. Because of its high reactivity, ozone decomposes into oxygen again in the water, with a half-life of several minutes.

Person in charge

The person who has supervisory responsibility for the day-to-day operation and control of the facility.


In chemistry, pH is a scale used to specify the acidity or basicity of an aqueous solution. Acidic solutions (solutions with higher concentrations of hydrogen ions) are measured to have lower pH values than basic or alkaline solutions. The pH scale is logarithmic and inversely indicates the concentration of hydrogen ions in the solution. At 25 °C, solutions with a pH less than 7 are acidic, and solutions with a pH greater than 7 are alkaline. Solutions with a pH of 7 at this temperature are neutral (e.g. pure water). The neutral value of the pH depends on the temperature, being lower than 7 if the temperature increases. By regulation, drinking water must have a pH comprised between 6.5 and 8.5.


In the context of water analysis, a photometer is an instrument that measures the light (electromagnetic radiation in the range from ultraviolet to infrared and including the visible spectrum) absorbed by a water sample. It is used, in combination with special reagents, for very precisely measuring a range of different chemical properties of water.


Location where water is used e.g. shower head, tap outlet.


Drinking water, also known as potable water, is water that is safe to drink or use for food preparation.


Rigid polyvinyl chloride (uPVC) is a synthetic plastic polymer with high hardness and good mechanical and insulation properties. It is chemically resistant to acids, salts, bases, fats, and alcohols. Roughly half of the world’s PVC resin manufactured annually is used for producing pipes for municipal and industrial applications.

Residential aged care facility

A facility at which an approved provider provides residential care under the Aged Care Act 1997 (Commonwealth).

Reticulated non-potable

Non-drinking water reticulation system.

Reticulated potable

Network of pipes that only carry drinking water.

Return loop

A plumbing configuration where the hot/warm water pipe continues from one tap to the next in a loop back to the same location (normally the cold water inlet to the hot/warm water system).


The likelihood that a hazard or hazardous event will cause harm to humans in a specific timeframe and the consequences (and magnitude) of the harm.

(Water) Risk management plan

Documented, risk-based strategy to ensure water-related hazards, such as Legionella are managed to ensure the protection of public health.

Sanitation / Sanitization

While cleaning is all about removing the dirt and impurities, sanitization is all about killing and eradicating the bacteria, germs, pathogenic, and non-pathogenic microorganisms that grow on various surfaces. The word ‘sanitation’ is also sometimes used, although it is not strictly a synonym, as it refers to the maintenance of hygienic conditions through services such as waste collection and wastewater disposal.

SCADA system

Supervisory control and data acquisition (SCADA) is a system of software and hardware elements that allows to:

  • monitor, gather, and process real-time data
  • directly interact with devices (e.g. sensors, valves, etc.) through a human-machine interface (HMI) software
  • record events into a log file
Scald / scalding

A form of thermal burn resulting from exposure to hot water or steam.

Tapware aerator

A small attachment that fits either onto the end of the tap or inside of the existing spout. It will control the amount of water that flows through the tap without affecting the water pressure, creating a no-splashing stream and often delivering a mixture of water and air.

Tempering devices

A device that mixes hot and cold water to deliver water at a desired temperature.

Thermostatic mixing valve (TMV)

A valve that automatically blends hot water with cold water to deliver warm water for sanitary purposes to prevent scalding.

Total chlorine

Chlorine present in the form of “free chlorine” of “combined chlorine” or both.

Ultraviolet (UV) disinfection

Non-chemical disinfection process which kills microorganisms by a physical process. UV-C radiation, with a wavelength ranging from 240 to 280 nm, attacks the vital DNA of the bacteria directly. Suspended particles are a problem because microorganisms buried within particles are shielded from the UV light and pass through the unit unaffected. Water flow rate is a key factor of UV water treatment: if the flow is too high, water will pass through without sufficient UV exposure; if the flow is too low, heat may build up and damage the UV lamp.

Unacceptable level of risk

Any level of risk not considered an acceptable level of risk. These risks must have controls applied such that they are no longer unacceptable.

Unused outlet

An outlet that is not used, for example, a basin located in a room converted into an office/storeroom. This can create a dead leg.

Verification monitoring

Scheduled but not real-time monitoring of specific parameters to verify the effectiveness of the water risk management plan in managing the risks posed by the water within the water distribution system (e.g. testing for Legionella).

Warm water system

A heated water system that distributes warm water at approximately 45°C throughout the majority or all of the water distribution system, for sanitary purposes to prevent scalding.

Water distribution system

Infrastructure within a facility from every point where water enters the facility through the infrastructure to every point where the water is used.


The WaterMark™ Certification Scheme is a mandatory scheme for plumbing and drainage products of a certain type. Certification ensures products are fit for purpose and appropriately authorised for use in plumbing and drainage installations. The Australian Building Codes Board administers and manages the Scheme. WaterMark™ product certification protects community health and safety. A certified product is fit for purpose and authorised for installation by a licensed plumber.

Water-related hazards

Microorganisms, substances, or physical properties of water that are reasonably expected to cause injury or illness to an individual.

Water stagnation

The condition where water ceases to flow and is liable to enhance microbiological growth.

Water stagnation

The condition where water ceases to flow and is liable to enhance microbiological growth.

Water storages

Tanks or other storage vessels where water, after entering a facility, may be stored for a period of time, before being used within a facility.

Water treatment

Processes used to make the water more acceptable for its end use e.g. chlorination via a chlorine dosing unit.