| #R001 | operational | operational | mandatory | Minimum disinfectant residual concentration | drinking water | requirement | > 0.2 mg/L | There is increasing recognition that a minimum disinfectant residual concentration greater than 0.2 mg/L is required to control microbiological (re)growth in the distribution system. | Required to control microbiological (re)growth in the distribution system | high |
| #R002 | operational | operational | recommended | Free chlorine residual for biofilm control | drinking water | requirement | 1.0 mg/L | Studies indicate that disinfectant residual concentrations in the order of 1.0 mg/L free chlorine (for systems that chlorinate) [...] are required for controlling biofilm formation | For systems that chlorinate | high |
| #R003 | operational | operational | recommended | Total chlorine residual for biofilm control | drinking water | requirement | 1.8 mg/L | Studies indicate that disinfectant residual concentrations in the order of [...] 1.8 mg/L total chlorine (for systems that chloraminate) are required for controlling biofilm formation | For systems that chloraminate | high |
| #R004 | physical | operational | recommended | Cold water temperature in premise plumbing | drinking water | requirement | < 20 °C | keeping temperatures of cold and hot water systems outside of the ideal range for microorganism growth (e.g., cold water less than 20°C) | Premise plumbing system management | high |
| #R005 | physical | health | mandatory | Hot water tank temperature | drinking water | requirement | > 60 °C | keeping temperatures of [...] hot water tank temperature greater than 60°C | Premise plumbing system management; NPC specifications | high |
| #R006 | physical | operational | recommended | Hot water line distal point temperature | drinking water | treatment_goal | > 55 °C | hot water lines at distal points ideally greater than 55°C | Premise plumbing system management | high |
| #R007 | microbiological | health | guideline | Legionella concentration action level | drinking water | requirement | 50000 CFU/L | a Legionella concentration of 50,000 CFU/L warrants concern and should be considered an action level to trigger remedial activities | Applies to various water systems (cooling towers, buildings, etc.) | high |
| #R008 | physical | health | mandatory | Maximum water outlet temperature at the tap | drinking water | requirement | <= 49 °C | The NPC specifies that water valves supplying showerheads and bathtubs should be capable of maintaining a water outlet temperature that does not exceed 49°C in order to reduce the risk of scalding | Showerheads and bathtubs | high |
| #R009 | operational | health | recommended | Free chlorine residual for Naegleria fowleri control | drinking water | requirement | 0.5 mg/L | Maintaining a minimum free chlorine residual of 0.5 mg/L throughout the distribution system is recommended for the control of N. fowleri in vulnerable drinking water systems | Vulnerable drinking water systems | high |
| #R010 | operational | health | recommended | Chloramine residual best practice for Naegleria fowleri | drinking water | treatment_goal | > 1.5 mg/L | The suggested best practice for a chloramine residual of greater than 1.5 mg/L throughout the distribution system (Health Canada, 2020b) is sufficient for N. fowleri control | Distribution system residual maintenance | high |
| #R011 | microbiological | operational | guideline | Aeromonas operational target limit | drinking water | OG | < 1000 CFU/100 mL | In the Netherlands, Dutch drinking water legislation specifies a monitoring requirement for Aeromonas as an operational parameter. | Based on treatment achievability, not public health significance | high |
| #R012 | microbiological | health | guideline | Legionella action level (EU Directive) | drinking water | MAC | 1000 CFU/L | The 2020 European Union Drinking Water Directive includes an action level for Legionella in premise plumbing systems. | Premise plumbing systems | high |
| #R013 | operational | operational | recommended | Free chlorine residual for Pseudomonas control | drinking water | OG | > 0.3 mg/L | Laboratory-scale and pilot-scale studies suggest that maintaining free chlorine residuals above 0.3 mg/L is useful for control of Pseudomonas spp. in bulk water. | Bulk water control; long-term continuous exposure recommended | high |
| #R014 | operational | operational | recommended | Free chlorine residual for Legionella in healthcare | drinking water | OG | 0.3 - 0.5 mg/L | Guidance materials on Legionella control in plumbing systems for health-care facilities have recommended minimum disinfectant residual targets. | Health-care facility plumbing systems | high |
| #R015 | operational | operational | recommended | Monochloramine residual for Legionella in healthcare | drinking water | OG | 1.5 mg/L | Guidance materials on Legionella control in plumbing systems for health-care facilities have recommended minimum disinfectant residual targets. | Health-care facility plumbing systems | high |
| #R016 | physical | treatment | recommended | Thermal shock (heat shock) remediation | drinking water | treatment_goal | 70 °C | Temporarily elevating the water temperature, or heat shock (e.g., a stringent thermal shock of 70°C for 30 minutes), has been utilized as a control measure. | Extreme remediation measure for building systems | high |
| #R017 | operational | treatment | recommended | Free chlorine CT for 2-log inactivation of biofilm-associated Legionella pneumophila | drinking water | requirement | 8.86 mg∙min/L | CT values were determined for Legionella pneumophila strain Philadelphia-1 serogroup 1 when associated with biofilm on PVC material. | pH = 8, temperature = 21 °C; associated with biofilm on PVC | high |
| #R018 | operational | treatment | recommended | Monochloramine CT for 2-log inactivation of biofilm-associated Legionella pneumophila | drinking water | requirement | 17.16 mg∙min/L | CT values were determined for Legionella pneumophila strain Philadelphia-1 serogroup 1 when associated with biofilm on PVC material. | pH = 8, temperature = 21 °C; associated with biofilm on PVC | high |
| #R019 | operational | treatment | guidance | Free chlorine CT for Naegleria fowleri cysts (4-log inactivation) | drinking water | requirement | 31 - 37 mg∙min/L | Relative CT values for various waterborne pathogens, free chlorine. | 5-25°C, pH 6-9; 4-log inactivation | high |
| #R020 | operational | treatment | guidance | Free chlorine CT for Mycobacterium avium (3-log removal) | drinking water | requirement | 51 - 1552 mg∙min/L | Relative CT values for various waterborne pathogens, free chlorine. | 5-25°C, pH 6-9; 3-log removal | high |
| #R021 | operational | treatment | guidance | Free chlorine CT for Acanthamoeba species cysts (2-log inactivation) | drinking water | requirement | 1300 mg∙min/L | Relative CT values for various waterborne pathogens, free chlorine. | 5-25°C, pH 6-9; 2-log inactivation | high |
| #R022 | operational | treatment | guidance | UV dose for Naegleria fowleri cysts (4-log inactivation) | drinking water | requirement | 121 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens (4 log inactivation). | 4-log inactivation | high |
| #R023 | operational | treatment | guidance | UV dose for Acanthamoeba spp. cysts (4-log inactivation) | drinking water | requirement | 167 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens (4 log inactivation). | 4-log inactivation | high |
| #R024 | operational | treatment | guidance | UV dose for Adenovirus (4-log inactivation) | drinking water | requirement | 51 - 261 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens (4 log inactivation). | 4-log inactivation | high |
| #R025 | operational | treatment | recommended | Free chlorine CT for 3-log inactivation of biofilm-associated Legionella pneumophila | drinking water | requirement | 36.11 mg∙min/L | CT values determined for Legionella pneumophila strain Philadelphia-1 serogroup 1 associated with biofilm on PVC | pH = 8, temperature = 21 °C | high |
| #R026 | operational | treatment | recommended | Free chlorine CT for 4-log inactivation of biofilm-associated Legionella pneumophila | drinking water | requirement | 63.67 mg∙min/L | CT values determined for Legionella pneumophila strain Philadelphia-1 serogroup 1 associated with biofilm on PVC | pH = 8, temperature = 21 °C | high |
| #R027 | operational | treatment | recommended | Monochloramine CT for 3-log inactivation of biofilm-associated Legionella pneumophila | drinking water | requirement | 62.80 mg∙min/L | CT values determined for Legionella pneumophila strain Philadelphia-1 serogroup 1 associated with biofilm on PVC | pH = 8, temperature = 21 °C | high |
| #R028 | operational | treatment | recommended | Monochloramine CT for 4-log inactivation of biofilm-associated Legionella pneumophila | drinking water | requirement | 108.44 mg∙min/L | CT values determined for Legionella pneumophila strain Philadelphia-1 serogroup 1 associated with biofilm on PVC | pH = 8, temperature = 21 °C | high |
| #R029 | operational | treatment | recommended | Contact time for 2-log inactivation of biofilm-associated Legionella (0.2 mg/L Free Chlorine) | drinking water | requirement | 44.3 minutes | Required time in a distribution system for 2 log inactivation based on Table 3 CT values | Assuming 0.2 mg/L Free Chlorine residual | high |
| #R030 | operational | treatment | recommended | Contact time for 2-log inactivation of biofilm-associated Legionella (1.0 mg/L Monochloramine) | drinking water | requirement | 17.2 minutes | Required time in a distribution system for 2 log inactivation based on Table 3 CT values | Assuming 1.0 mg/L Monochloramine residual | high |
| #R031 | operational | treatment | guidance | UV dose for Cryptosporidium and Giardia (4-log inactivation) | drinking water | treatment_goal | 22 mJ/cm2 | Relative UV dose requirements for 4 log inactivation | 4-log inactivation | high |
| #R032 | operational | treatment | guidance | Free chlorine CT for Aeromonas species (2-log inactivation) | drinking water | requirement | 0.2 - 1.4 mg∙min/L | Relative CT values for various waterborne pathogens, Free chlorine | 5-25°C, pH 6-9; 2-log inactivation | high |
| #R033 | operational | treatment | guidance | Free chlorine CT for Pseudomonas species (2-log inactivation) | drinking water | requirement | 0.0073 - 4.3 mg∙min/L | Relative CT values for various waterborne pathogens, free chlorine. | 5-25°C, pH 6-9; 2-log inactivation | high |
| #R034 | operational | treatment | guidance | Free chlorine CT for E. coli, Campylobacter, Helicobacter, Salmonella, and Yersinia (2-log inactivation) | drinking water | requirement | 0.034 - 5.1 mg∙min/L | Relative CT values for various waterborne pathogens, free chlorine. | 5-25°C, pH 6-9; 2-log inactivation | high |
| #R035 | operational | treatment | guidance | Free chlorine CT for Enteric viruses (2-log inactivation) | drinking water | requirement | 0.01 - 12 mg∙min/L | Relative CT values for various waterborne pathogens, free chlorine. | 5-25°C, pH 6-9; 2-log inactivation | high |
| #R036 | operational | treatment | guidance | Free chlorine CT for Legionella pneumophila (3 to 4-log removal) | drinking water | requirement | 0.1 - 0.3 mg∙min/L | Relative CT values for various waterborne pathogens, free chlorine. | 5-25°C, pH 6-9; 3-4 log removal | high |
| #R037 | operational | treatment | guidance | Free chlorine CT for Giardia cysts (2-log inactivation) | drinking water | requirement | 25 - 99 mg∙min/L | Relative CT values for various waterborne pathogens, free chlorine. | 5-25°C, pH 6-9; 2-log inactivation | high |
| #R038 | design | treatment | guideline | Typical design CT for 4 log virus inactivation | drinking water | requirement | 12 - 15 mg∙min/L | Typical design CTs that are required to achieve 4 log virus inactivation | Standard design conditions for virus inactivation | high |
| #R039 | design | treatment | guideline | Typical design CT for 0.5 log Giardia inactivation | drinking water | requirement | 35 - 65 mg∙min/L | Typical design CTs that are required to achieve 0.5 log Giardia inactivation | Standard design conditions for Giardia inactivation | high |
| #R040 | operational | treatment | guidance | UV dose for Pseudomonas species (4-log inactivation) | drinking water | requirement | 3.1 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens (4 log inactivation). | 4-log inactivation | high |
| #R041 | operational | treatment | guidance | UV dose for Aeromonas species (2-log removal) | drinking water | requirement | 2.5 - 8 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens | 2-log removal | high |
| #R042 | operational | treatment | guidance | UV dose for Legionella pneumophila (4-log inactivation) | drinking water | requirement | 11 - 30 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens (4 log inactivation). | 4-log inactivation | high |
| #R043 | operational | treatment | guidance | UV dose for E. coli, Campylobacter, Helicobacter, Salmonella, and Yersinia (4-log inactivation) | drinking water | requirement | 5 - 51 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens (4 log inactivation). | 4-log inactivation | high |
| #R044 | operational | treatment | guidance | UV dose for Hepatitis A, Coxsackievirus, Poliovirus, and Rotavirus (4-log inactivation) | drinking water | requirement | 16.4 - 61 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens (4 log inactivation). | 4-log inactivation | high |
| #R045 | operational | treatment | guidance | UV dose for Mycobacterium avium (4-log inactivation) | drinking water | requirement | 12.3 - 64 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens (4 log inactivation). | 4-log inactivation | high |
| #R046 | operational | treatment | guidance | UV dose for high-resistance strains of Mycobacterium species (2 to 5-log removal) | drinking water | requirement | 96 - 192 mJ/cm2 | Relative UV dose requirements for various waterborne pathogens | 2 to 5-log removal | high |
| #R047 | operational | treatment | recommended | Contact time for 2-log inactivation of biofilm-associated Legionella (0.5 mg/L Free Chlorine) | drinking water | requirement | 17.7 minutes | Required time in a distribution system for 2 log inactivation based on Table 3 CT values | Assuming 0.5 mg/L Free Chlorine residual | high |
| #R048 | operational | treatment | recommended | Contact time for 2-log inactivation of biofilm-associated Legionella (1.0 mg/L Free Chlorine) | drinking water | requirement | 8.9 minutes | Required time in a distribution system for 2 log inactivation based on Table 3 CT values | Assuming 1.0 mg/L Free Chlorine residual | high |
| #R049 | operational | treatment | recommended | Contact time for 2-log inactivation of biofilm-associated Legionella (1.5 mg/L Monochloramine) | drinking water | requirement | 11.4 minutes | Required time in a distribution system for 2 log inactivation based on Table 3 CT values | Assuming 1.5 mg/L Monochloramine residual | high |
| #R050 | operational | treatment | recommended | Contact time for 2-log inactivation of biofilm-associated Legionella (1.8 mg/L Monochloramine) | drinking water | requirement | 9.5 minutes | Required time in a distribution system for 2 log inactivation based on Table 3 CT values | Assuming 1.8 mg/L Monochloramine residual | high |
| #R051 | operational | treatment | recommended | Thermal shock (heat shock) duration | drinking water | treatment_goal | 30 minutes | heat shock (e.g., a stringent thermal shock of 70°C for 30 minutes) | Remediation measure in building systems | high |