AS 5667.5:2022 pdf free download – Water quality – Sampling Part 5: Guidance on sampling of drinking water from treatment works and piped distribution systems (ISo 5667-5:2006, MOD)

AS 5667.5:2022 pdf free download – Water quality – Sampling Part 5: Guidance on sampling of drinking water from treatment works and piped distribution systems (ISo 5667-5:2006, MOD).
This part of ISO 5667 establishes principles to be applied to the techniques of sampling water intended for human consumption.
For the purposes of this part of ISO 5667, water intended for human consumption comprises:
a) all water either in its original state or after treatment, intended for drinking, cooking, food preparation, or other domestic purposes, regardless of its origin, plus
b) all water used in any production undertaking for the manufacture, processing, preservation or marketing of products or substances intended for human consumption unless the competent national authorities are satisfied that the quality of the water cannot affect the wholesomeness of the foodstuff in its finished form.
The guidance given In this part of ISO 5667 Is confined to those circumstances where water Is drawn from municipal or similar distribution systems (including individual systems) where prior treatment and/or quality assessment has resulted in the water being classified as suitable for drinking or potable process purposes. Specifically, this part of ISO 5667 Is applicable to water that Is In continuous supply relative to any stage of use up to and Including the point of consumption in a distribution system. This includes distribution within large buildings in which additional water quality management might be applicable.
This part of ISO 5667 is also applicable to sampling situations that can arise relative to the investigation of system defects or emergency situations where the safety of sampling operatives is not compromised,
This part of ISO 5667 does not provide guidance for water sources or for products generated by using drinking water. The followings items are examples of cases not addressed by the present document:
— the sampling of source water, for example groundwater and surface water impoundments;
— sampling of drinking water supplies derived from non-continuous sources (for example, from road tankers);
— sampling of bulk storage of water on airplanes, trains and ships:
— the sa inpling of beverage products (Including bottled waters) or food containing potable water used in its preparation:
— sampling of drink vending machines that dispense unsealed cups of drinks,
Samples should be collected from the Inlet and outlet pipes as close as possible to the service reservoir. The outlet sample location should he upstream of the first customer.
If a service reservoir has a common inlet and outlet main, samples should, where possible, be collected when the main is acting as an outlet and the water quality is therelore representative of water that has been stored in the service reservoir. If this cannot be achieved, a sample collection pumping system should be installed and utihzed.
It a service reservoir has more than one compartment but the compartments are hydraulically connected, the compartments may be regarded as a single reservoir. II a service reservoir has more than one compartment and these compartments are not hydraulically connected, each compartment should be considered as a separate service reservoir and should be assigned individual sampling points, except if the individual outlets from the compartments combine Into a common outlet, In which case a single sample location on the common outlet might be adequate.
Sometimes (for example, when a reservoir has been out of service or cleaned, when there is no sampling valve on the outlet pipe, or when the surface layer of the reservoir is to be analysed), it might he necessary to take dip samples, as described in from the service reservoirs, although this means of sampling should be avoided wherever possible. If it Is essential to take dip samples, special care should be taken to ensure that the sampling operation does not introduce debris into the water and that equipment is sterilized before sampling to avoid a microbiological compromise of the water in the reservoir.
5.3 Water treatment plants
Samples should be collected from the inlet and outlet pipes as close as possible to the treatment plant. For monitoring of the different stages (for example, sedimentation and filtration) of water treatment, sampling should take place before and after the respective stage being monitored. If there is disinfection and/or an oxidation plant, sampling should be carried out as described in £4.
There usually is an expectation that water is better after treatment. Equipment that is inappropriate, or equipment that was poorly installed or inadequately maintained can, however, introduce contaminants and compromise microbiological quality. Additionally, some materials used to coat pipes can introduce low concentrations of contaminants such as ethylbenzene or xylenes.