P6.3.1.1 Use filters that are National or Cloudiness in Change to a certified, or have international the water different type Incorrect type been assessed, as certificate of following of filter. of cartridge being capable of filter’s filtration. filter. Keep list of removing particles capabilities.2 Filter unable to filters that are down to 2–3 m in Record of filter remove more compatible size. See Footnote 2 types used. than 99.9% of with the of Section 3.2.3.1 of particles housing in Particle DWSNZ: 2000. greater than 2-3 use. counting or Make sure filter µm in size. microscopic cartridge is particle Customer compatible with the analysis test complaints. filter housing and results, or the Cases of record the type of results of any giardiasis or filter used. other test approved by in the the Ministry of community Health. associated with periods of poor water quality. Wrong filter type used. 1 The consequences of the event, and therefore the level of risk, will be influenced by the quality of the source water and the type and effectiveness of any disinfection after cartridge filtration. 2 For example, certification under NSF Standard 53 or AS/NZ 4348:1995. Preventive measures Checking preventive measures Corrective action Causes What to check Signs that action is needed Event: FILTER NOT REMOVING PARTICLES DOWN TO 2-3 µm IN SIZE cont’d P6.3.1.2 Check the condition Keep record Cloudiness in Determine of the filter housing of any damage the water whether it is Damage to the and the cartridge observed. following the cartridge seal (cartridge seal when changing filtration. or housing or filter Filter filters. that is housing). maintenance Filter unable to damaged, and Make sure the log. remove more replace person replacing than 99.9% of Particle damaged unit. the cartridges particles counting or knows the correct greater than Train staff if microscopic way to do it. 23 µm in size necessary. particle entering it. analysis test Read filter results, or the Customer results of any complaints. instructions. other test Cases of approved by giardiasis or the Ministry of Health. in the community associated with periods of poor water quality. Frequent damage to seal.
P6.3.1.1 Incorrect type of cartridge filter. Use filters that are certified, or have been assessed, as being capable of removing particles down to 2–3 m in size. See Footnote 2 of Section 3.2.3.1 of DWSNZ: 2000. Make sure filter cartridge is compatible with the filter housing and record the type of filter used. National or international certificate of filter’s capabilities.2 Record of filter types used. Particle counting or microscopic particle analysis test results, or the results of any other test approved by the Ministry of Health. Cloudiness in the water following filtration. Filter unable to remove more than 99.9% of particles greater than 2-3 µm in size. Customer complaints. Cases of giardiasis or in the community associated with periods of poor water quality. Wrong filter type used. Change to a different type of filter. Keep list of filters that are compatible with the housing in use. 1 The consequences of the event, and therefore the level of risk, will be influenced by the quality of the source water and the type and effectiveness of any disinfection after cartridge filtration. 2 For example, certification under NSF Standard 53 or AS/NZ 4348:1995. Causes Preventive measures Checking preventive measures Corrective action What to check Signs that action is needed Event: FILTER NOT REMOVING PARTICLES DOWN TO 2-3 µm IN SIZE cont’d P6.3.1.2 Damage to the seal (cartridge or filter housing). Check the condition of the filter housing and the cartridge seal when changing filters. Make sure the person replacing the cartridges knows the correct way to do it. Keep record of any damage observed. Filter maintenance log. Particle counting or microscopic particle analysis test results, or the results of any other test approved by the Ministry of Health. Cloudiness in the water following filtration. Filter unable to remove more than 99.9% of particles greater than 23 µm in size entering it. Customer complaints. Cases of giardiasis or in the community associated with periods of poor water quality. Frequent damage to seal. Determine whether it is the cartridge or housing that is damaged, and replace damaged unit. Train staff if necessary. Read filter instructions.