| Req ID | Category | Intent | Legal Status | Name | Subdomain(s) | Context | Conditions | Confidence |
|---|---|---|---|---|---|---|---|---|
| #Q001 | treatment | treatment | mandatory | Disinfection Effectiveness Protection | drinking water | Any measures taken to limit the concentration of chloramines or their by-products in drinking water supplies must not compromise the effectiveness of disinfection. | When taking measures to limit chloramines or their by-products. | high |
| #Q002 | treatment | health | recommended | Public Water Supply Disinfection | drinking water | All public drinking water supplies should be disinfected, unless specifically exempted by the responsible authority. | Applies to all public drinking water supplies unless exempted. | high |
| #Q003 | monitoring | operational | recommended | Source Water Ammonia Characterization | drinking water | Since chloramines can also be formed when ammonia is present in source water, utilities should characterize their source water to assess the presence of and variability of ammonia levels. | high | |
| #Q004 | administrative | operational | recommended | Assessment of Conversion Impacts | drinking water | When utilities are considering conversion from chlorine to chloramines, they should assess the impacts on their water quality and system materials, including the potential for corrosion, nitrification and the formation of disinfection by-products. | When considering conversion from chlorine to chloramines. | high |
| #Q005 | operational | operational | recommended | Maintenance of Stable Residual | drinking water | Monochloramine, used as a secondary disinfectant, should be applied so as to maintain a stable residual concentration throughout the distribution system. | When monochloramine is used as a secondary disinfectant. | high |
| #Q006 | operational | aesthetic | recommended | Consideration of Taste and Odour | drinking water | Although taste and odour concerns do not make the water unsafe to consume, they should be taken into account during the selection of operational and management strategies for the water treatment and distribution systems. | high | |
| #Q007 | operational | operational | recommended | Establishment of Operational Targets | drinking water | Utilities should establish operational targets for a disinfectant residual concentration appropriate for their system. | high | |
| #Q008 | reporting | health | recommended | Notification of Chloramination to Vulnerable Users | drinking water, other | Dialysis treatment providers at all levels—large facilities/hospitals, small community facilities, mobile units, providers for independent/home dialysis—as well as aquarium owners should be notified that water is chloraminated. | When the drinking water supply is chloraminated. | high |
| #Q009 | monitoring | operational | recommended | Daily Monitoring of Chlorine Residual | drinking water | Utilities using chloramines for secondary disinfection should, at minimum, monitor total and free chlorine residual daily in water leaving the treatment plant and throughout the distribution system. | When utilities use chloramines for secondary disinfection. | high |
| #Q010 | monitoring | operational | recommended | Disinfectant Residual Sampling Locations | drinking water | Disinfectant residual sampling should be conducted at the point of entry (baseline) and throughout the distribution system. | high | |
| #Q011 | monitoring | operational | recommended | Representative Sample Location Choice | drinking water | Sample locations should be chosen to represent all areas of the distribution system. | high | |
| #Q012 | monitoring | operational | recommended | System-Specific Nitrification Monitoring Plan | drinking water | It is recommended that system-specific monitoring plans be developed that include actions to be taken under various water quality conditions relating to nitrification. This plan should include monitoring of finished water and of locations throughout the distribution system including storage facilities and areas of low flow and high water age. | For water utilities that are chloraminating. | high |
| #Q013 | monitoring | operational | recommended | Nitrification Monitoring Parameters | drinking water | Parameters to monitor should include monochloramine, total chloramine, free and total chlorine, free and total ammonia, nitrite, nitrate, adenosine triphosphate (ATP), temperature, pH and alkalinity. | When monitoring for nitrification. | high |
| #Q014 | reporting | operational | recommended | Graphing Results for Trends and Alerts | drinking water | Results should be graphed to evaluate trends and establish alert and action levels that are system-specific. | high | |
| #Q015 | reporting | operational | recommended | Graphing Percent Monochloramine | drinking water | The percent of monochloramine to total chloramine should also be calculated and graphed to determine if organic chloramines are present. | high | |
| #Q016 | administrative | reporting | recommended | Establishment of Monitoring Frequency | drinking water | The monitoring frequency should be established in conjunction with the responsible drinking water authority. | high | |
| #Q017 | monitoring | operational | recommended | Nitrification Parameter Trigger | drinking water | Changes in the trends of nitrification parameters should also trigger more frequent monitoring. | When trends in nitrification parameters change. | high |
| #Q018 | treatment | unknown | mandatory | Aquarium Chloramine Mitigation | other | To mitigate the impact of chlorine or chloramines, aquarium owners must ensure the use of proper aeration or chlorine/chloramine quenching | For aquarium owners. | high |
| #Q019 | operational | operational | recommended | Determination of Breakpoint Ratio | drinking water | For a utility wishing to produce monochloramine, the breakpoint ratio should be determined experimentally for each water subply. | When a utility wishes to produce monochloramine. | high |
| #Q020 | operational | treatment | guidance | Sufficient Contact Time for Breakpoint Chlorination | drinking water | It is important to allow for sufficient contact time to ensure that breakpoint chlorination has occurred and primary disinfection is complete. | high | |
| #Q021 | administrative | unknown | recommended | Analysis Directed by Drinking Water Authority | drinking water | Analyses should be carried out as directed by the responsible drinking water authority in the affected jurisdiction. | high | |
| #Q022 | operational | operational | guidance | Field Staff Training for DPD Method | drinking water | When using the DPD colorimetric test, it is important to ensure that field staff is well-trained to do both free and total chlorine measurements. | When using the DPD colorimetric test. | high |
| #Q023 | administrative | operational | recommended | Consultation on Method Interferences | drinking water | Users should consult with the manufacturer regarding method interferences, interfering substances and any associated corrective steps that may be necessary. | high | |
| #Q024 | administrative | operational | recommended | QA/QC Program for Analysers | drinking water | To make accurate measurements using these units, water utilities should develop a quality assurance and quality control (QA/QC) program such as those outlined in SM 3020 (APHA et al., 2017). | When making measurements using online and portable analysers. | high |
| #Q025 | monitoring | operational | recommended | Periodic Verification of Results | drinking water | In addition, periodic verification of results using an accredited laboratory is recommended. | When using online and portable analysers. | high |
| #Q026 | administrative | reporting | recommended | Authority Acceptance of Analyser Results | drinking water | Water utilities should check with the responsible drinking water authority in the appropriate jurisdiction to determine if results from these units are acceptable. | When using online and portable analysers. | high |
| #Q027 | operational | treatment | mandatory | Consider Impacts Prior to Blending Waters | drinking water | Utilities need to carefully consider impacts on the distribution system prior to blending chloraminated and chlorinated waters to meet their specific situation so as to ensure that water will have acceptable disinfection | Prior to blending chloraminated and chlorinated waters. | high |
| #Q028 | administrative | operational | recommended | Annual Review of Sampling Programs | drinking water | Sampling programs should be reviewed annually to examine historical data, water use patterns/changes, as well as any changes in water treatment or distribution system operation | high | |
| #Q029 | operational | operational | recommended | Set Target Disinfectant Residuals | drinking water | These manuals recommend that utilities set system-specific disinfectant residual targets based on their water quality objectives and system characteristics, and that they ensure chloramine concentrations leaving the treatment plant are sufficient to achieve their established target residual | high | |
| #Q030 | monitoring | operational | recommended | Site-Specific Water Quality and Corrosion Studies | drinking water | It is strongly recommended that site-specific water quality/corrosion studies be conducted to capture the complex interactions of water quality, distribution system materials and treatment chemicals used in each individual water system. | When changing disinfection practices to chloramination. | high |
| #Q031 | monitoring | operational | mandatory | Frequent Monitoring of Source Ammonia Parameters | drinking water | In both cases, frequent monitoring of relevant parameters (ammonia; combined, total and free chlorine) is needed to ensure that objectives are achieved at all times. | When forming chloramines to remove source ammonia or performing breakpoint chlorination. | high |
| #Q032 | operational | operational | mandatory | Proper Control During Booster Chloramination | drinking water | Booster chloramination requires proper control to ensure excess ammonia is not added as this may lead to nitrification | During booster chloramination. | high |
| #Q033 | administrative | operational | mandatory | Development of Nitrification Monitoring Programs | drinking water | Development of nitrification monitoring programs is critical for utilities that use chloramines | For utilities that use chloramines. | high |
| #Q034 | monitoring | health | recommended | Monitoring for Lead Release Following Treatment Changes | drinking water | ...any changes made to the treatment process, particularly those that affect water quality parameters such as pH, alkalinity and ORP (e.g., changing residual disinfectant from chlorine to chloramines), should be accompanied by close monitoring for lead release to assess the need for corrosion control. | When making changes to the treatment process affecting pH, alkalinity, or ORP. | high |
| #Q035 | prohibition | health | recommended | Prohibition of Disinfectant Removal | drinking water | Although private residential drinking water treatment devices may be an option for reducing concentrations of chloramines in drinking water if the consumer finds the taste objectionable, removal of the disinfectant is not recommended. | For consumers using private residential drinking water treatment devices. | high |
| #Q036 | treatment | health | recommended | Use of Certified Treatment Devices | drinking water | Health Canada does not recommend specific brands of drinking water treatment devices, but it strongly recommends that consumers use devices that have been certified by an accredited certification body as meeting the appropriate NSF/ANSI drinking water treatment unit standards. | When consumers use residential drinking water treatment devices. | high |
| #Q037 | operational | operational | recommended | System-Specific Determination of Chloramine Concentration | drinking water | Where chloramines are used as a drinking water disinfectant, it is recommended that their concentration be determined on a system-specific basis to ensure effectiveness of disinfection and maintenance of an appropriate residual while minimizing by-product formation and aesthetic concerns. | Where chloramines are used as a drinking water disinfectant. | high |
| #Q038 | monitoring | reporting | recommended | Monitoring Frequency Assessment | drinking water | The frequency of monitoring should be determined based on a system-specific assessment and ideally should be sufficient to characterize short-term and long-term temporal (e.g., hours, days, weeks, months) changes. | high | |
| #Q039 | monitoring | operational | guidance | Representative Remote Sampling Strategy | drinking water | A useful strategy is to target an increased number of remote locations throughout the drinking water distribution system, including dead ends and areas of low flow, to provide a more representative assessment of residual achieved and to identify any problem areas. | high | |
| #Q040 | monitoring | operational | recommended | Seasonal Sampling Frequency Increase | drinking water | Some utilities should also consider increasing the frequency of sampling during warmer months (August to October are typical nitrification months). | During warmer months. | high |
| #Q041 | monitoring | operational | guidance | Monitoring Frequency Reduction Eligibility | drinking water | Utilities that undertake comprehensive preventive measures and have baseline data indicating that nitrification does not occur in the system may conduct less frequent monitoring. | When comprehensive preventive measures are in place and baseline data shows no nitrification. | high |
| #Q042 | monitoring | operational | guidance | Sampling Tap Methodology | drinking water | Dedicated sampling taps are an ideal approach for residual sampling. | high | |
| #Q043 | monitoring | operational | guidance | Hydrant Sampling Methodology | drinking water | Hydrants can also be used for residual sampling, following best management practices and utilizing proper equipment to obtain an appropriate sample. | high | |
| #Q044 | operational | operational | recommended | Operator Disinfectant Residual Maintenance | drinking water | Given the operational benefits of secondary disinfection, operators should strive to maintain a stable disinfectant residual throughout the system. | high | |
| #Q045 | treatment | treatment | recommended | Disinfectant Residual Adjustment | drinking water | When applying monochloramine as a disinfectant, utilities should be aware of their target disinfectant residual value, and adjustments should be made to address monochloramine demand and decay. | When applying monochloramine as a disinfectant. | high |
| #Q046 | operational | operational | guidance | Flushing Technique Selection | drinking water | It is important that water utilities identify and implement the most appropriate flushing technique. | When performing distribution system flushing. | high |
| #Q047 | design | unknown | recommended | Elastomer Degradation By-product Consideration | drinking water | The possibility of release of other compounds and degradation by-products should also be considered. | When selecting elastomer materials. | high |
| #Q048 | administrative | aesthetic | guidance | Conversion Taste and Odour Awareness | drinking water | it is important that utilities contemplating a conversion to monochloramine remain aware of the potential for taste and odour concerns during the selection of operational and management strategies. | When contemplating a conversion to monochloramine. | high |
| #Q049 | monitoring | operational | recommended | Specific Sampling Location Requirements | drinking water | Key points for sampling also include the entry point to the distribution system (baseline), storage facilities, upstream and downstream of rechloramination booster stations, in areas of low flow or high water age, in areas of various system pressures, in mixed zones (blend of chlorinated and chloraminated water) and in areas with various sizes and types of pipe material. | When choosing sample locations for disinfectant residual monitoring. | high |
| #Q050 | monitoring | operational | guidance | Investigative Sampling Allowance | drinking water | Additional samples can be added for investigative purposes. | high | |
| #Q051 | monitoring | operational | recommended | Microbiological Population Monitoring | drinking water | Monitoring of general microbiological populations in drinking water distribution systems is also useful for assessing system water quality. The frequency of monitoring should be determined based on a system-specific assessment and ideally should be sufficient to characterize short-term and long-term temporal (e.g., hours, days, weeks, months) changes. | high |
| Req ID | Category | Intent | Legal Status | Name | Subdomain(s) | Limit Type | Limit Value | Context | Conditions | Confidence |
|---|---|---|---|---|---|---|---|---|---|---|
| #P001 | operational | operational | recommended | Chloramine residual (leaving treatment plant) | drinking water | OG | 2 mg/L | Suggested best operational practices when used as part of a program for nitrification prevention and control | Leaving the treatment plant | high |
| #P002 | operational | operational | recommended | Chloramine residual (distribution system) | drinking water | OG | > 1.5 mg/L | Suggested best operational practices for nitrification prevention and control in the distribution system | At all monitoring points in the distribution system | high |
| #P003 | operational | health | recommended | Monochloramine residual (N. fowleri control) | drinking water | requirement | >= 0.5 mg/L | Strategies for the control of N. fowleri at impacted water utilities | Throughout the distribution system | medium |
| #P004 | design | aesthetic | mandatory | Monochloramine (NSF/ANSI Standard 42 treatment effluent) | drinking water | requirement | <= 0.5 mg/L | Systems certified under NSF/ANSI Standard 42 must be able to reduce an influent concentration of 3.0 ± 0.3 mg/L monochloramine to <=0.5 mg/L monochloramine | Residential-scale drinking water treatment devices | high |
| #P005 | chemical | health | mandatory | Chloramines (U.S. EPA MRDL) | drinking water | MAC | 4.0 mg/L | The U.S. EPA has established a maximum residual disinfectant level (MRDL) and MRDLG for chloramines | Measured as combined total chlorine (as Cl2) | high |
| #P006 | chemical | health | guideline | Monochloramine (WHO Guideline) | drinking water | MAC | 3 mg/L | World Health Organization established a drinking water guideline for monochloramine | high | |
| #P007 | chemical | health | guideline | Monochloramine (Australia Guideline) | drinking water | MAC | 3.0 mg/L | The Australian drinking water guideline for monochloramine | high | |
| #P008 | design | treatment | recommended | Cl2:NH3-N weight ratio (stability) | drinking water | requirement | 4.5:1–5:1 weight ratio | Optimized for monochloramine stability to minimize free ammonia and reduce the risk of nitrification | Standard treatment optimization | high |
| #P009 | design | treatment | recommended | pH for monochloramine stability | drinking water | requirement | > 8.0 pH | Optimal pH level for monochloramine stability when treatment processes are optimized | Standard treatment optimization | high |
| #P010 | operational | health | guideline | Chloramine residual for microbial control | drinking water | OG | > 1.0 mg/L | Required to maintain lower general microbiological populations, reduce coliform occurrences, and control biofilm development | General distribution system maintenance | high |
| #P011 | operational | health | guidance | Chloramine residual for iron pipe biofilm control | drinking water | OG | > 2.0 mg/L | Needed to reduce bacterial numbers by greater than 2 log in biofilms grown on iron pipe | Systems with iron pipe materials | high |
| #P012 | operational | treatment | recommended | Carbonate levels for lead management | drinking water | requirement | > 50 mg/L | Suggested management strategy to reduce lead release in chloraminating systems | Chloraminated systems with lead release risks | high |
| #P013 | operational | treatment | recommended | pH for lead/copper corrosion control | drinking water | requirement | > 8 pH | Suggested management strategy to reduce lead release in chloraminating systems | Chloraminated systems with lead release risks | high |
| #P014 | operational | operational | guideline | Chloramine residual (typical Canadian distribution) | drinking water | requirement | < 4 mg/L | Typical levels found in Canadian distribution systems where chloramines are used. | Canadian drinking water supplies. | high |
| #P015 | operational | treatment | guidance | pH range for monochloramine formation | drinking water | requirement | 6.5–9.0 pH | Conditions under which monochloramine formation occurs. | Neutral to alkaline conditions. | high |
| #P016 | operational | treatment | guidance | pH range for dichloramine formation | drinking water | requirement | 4.0–6.0 pH | Conditions optimum for the formation of dichloramine. | Acidic conditions. | high |
| #P017 | operational | treatment | guidance | pH for trichloramine formation | drinking water | requirement | < 4.4 pH | Conditions optimum for the formation of trichloramine. | Highly acidic conditions. | high |
| #P018 | operational | treatment | recommended | Chlorine:Ammonia molar ratio for lead management | drinking water | treatment_goal | 0.7:1 molar ratio | Suggested management strategy to reduce lead release in chloraminating systems. | Systems with lead release risks. | high |
| #P019 | operational | aesthetic | guidance | Monochloramine taste and odour complaint threshold | drinking water | AO | 3–3.7 mg/L | Concentration range where taste and odour complaints generally occur in the population. | General consumer sensitivities. | high |
| #P020 | operational | reporting | recommended | Chlorine residual monitoring frequency | drinking water | requirement | 1 daily | Utilities using chloramines for secondary disinfection should, at minimum, monitor total and free chlorine residual daily. | Water leaving the treatment plant and throughout the distribution system | high |
| #P021 | operational | operational | guidance | Nitrification monitoring frequency (off-season) | drinking water | requirement | 2 times per month | Example monitoring plan for nitrification parameters. | Between December and May | high |
| #P022 | operational | operational | guidance | Nitrification monitoring frequency (peak-season) | drinking water | requirement | 1 time per week | Example monitoring plan for nitrification parameters. | Leading up to and during the nitrification season (June through October) | high |
| #P023 | physical | aesthetic | guidance | Monochloramine taste threshold (sensitive) | drinking water | AO | 0.48 mg/L | Taste threshold derived from a trained panel of moderate- to highly-sensitive individuals. | Aesthetic detection | high |
| #P024 | physical | aesthetic | guidance | Monochloramine odour threshold (sensitive) | drinking water | AO | 0.65 mg/L | Odour threshold derived from a trained panel of moderate- to highly-sensitive individuals. | Aesthetic detection | high |
| #P025 | physical | aesthetic | guidance | Dichloramine taste threshold | drinking water | AO | 0.13 mg/L | Taste threshold for sensory detection of dichloramine. | Aesthetic detection | high |
| #P026 | physical | aesthetic | guidance | Dichloramine odour threshold | drinking water | AO | 0.15 mg/L | Odour threshold for sensory detection of dichloramine. | Aesthetic detection | high |
| #P027 | physical | aesthetic | guidance | Trichloramine odour threshold | drinking water | AO | 0.02 mg/L | Odour threshold concentration for trichloramine. | Aesthetic detection | high |
| #P028 | physical | aesthetic | guidance | Dichloramine taste/odour complaint threshold | drinking water | AO | < 0.8 mg/L | Threshold below which taste and odour complaints are generally not expected. | Standard distribution system conditions. | high |
| #P029 | physical | aesthetic | guidance | Dichloramine objectionable taste/odour range | drinking water | AO | 0.9–1.3 mg/L | Concentration range where tastes and odours are explicitly noted as objectionable. | Aesthetic sensory detection. | high |
| #P030 | physical | aesthetic | guidance | Dichloramine aesthetic cut-off | drinking water | AO | 0.5 mg/L | Conservative cut-off recommended by some utilities to prevent taste/odour issues. | Operational target for aesthetic quality. | high |
| #P031 | chemical | treatment | recommended | Free ammonia-nitrogen for hydrazine control | drinking water | treatment_goal | < 0.5 mg/L | Conditions required to minimize the formation of hydrazine as a chloramine byproduct. | Treatment process management. | high |
| #P032 | chemical | treatment | recommended | pH for hydrazine minimization | drinking water | treatment_goal | < 9 pH | Maintaining pH below this level helps limit hydrazine formation from ammonia/monochloramine reactions. | Treatment process management. | high |
| #P033 | chemical | health | recommended | Hydrazine formation target | drinking water | treatment_goal | < 5 ng/L | Target concentration achieved when free ammonia and pH are controlled. | Resulting byproduct level in treated water. | high |
| #P034 | operational | reporting | guidance | SM 4500-Cl D dilution recommendation | drinking water | requirement | > 2 mg/L | Analytical procedure requirement for amperometric titration. | During chlorine residual measurement. | high |
| #P035 | operational | reporting | guidance | ASTM D1253 maximum recommended concentration | drinking water | requirement | 10 mg/L | Operating range for the standard test method for residual chlorine. | Amperometric titration analysis. | high |
| #P036 | operational | reporting | guidance | Hach 10260 acidity interference threshold | drinking water | requirement | > 150 mg/L CaCO3 | Operational limit for the DPD Chemkey method where acidity interferes with results. | Measurement of total or free chlorine residual. | high |
| #P037 | operational | reporting | guidance | Hach 10260 alkalinity interference threshold | drinking water | requirement | > 250 mg/L CaCO3 | Operational limit for the DPD Chemkey method where alkalinity interferes with results. | Measurement of total or free chlorine residual. | high |
| #P038 | operational | reporting | guidance | Method Detection Limit (SM 4500-Cl G) | drinking water | requirement | 10 µg/L | Detection limit for the N,N-diethyl-p-phenylenediamine (DPD) colorimetric method. | Standardized laboratory measurement of total, free, or combined chlorine. | high |
| #P039 | operational | reporting | guidance | Method Detection Limit (SM 4500-Cl F) | drinking water | requirement | 18 µg/L | Detection limit for the N,N-diethyl-p-phenylenediamine (DPD) ferrous method. | Standardized laboratory measurement of total, free, or combined chlorine. | high |
| #P040 | operational | reporting | guidance | Method Detection Limit (Hach 10260) | drinking water | requirement | 0.04 mg/L | Detection limit for the DPD Chemkey method. | Measurement of total or free chlorine. | high |
| #P041 | physical | aesthetic | guidance | Monochloramine aesthetic concentration threshold | drinking water | AO | < 5 mg/L | Level below which monochloramine normally does not contribute significantly to objectionable taste and odour. | Presence in drinking water. | high |
| #P042 | physical | aesthetic | guidance | Di- and Trichloramine aesthetic composition threshold | drinking water | AO | > 20 % | Composition level of total chloramines above which taste and odour complaints are more likely. | Ratio of di- and tri- species to total chloramine concentration. | high |
| #P043 | design | treatment | guidance | Theoretical Cl2:NH3-N weight ratio for breakpoint chlorination | drinking water | treatment_goal | 7.6:1 weight ratio | The theoretical weight ratio for reaching breakpoint chlorination in ammoniacal water. | Standard chemistry in aqueous media | high |
| #P044 | operational | treatment | guidance | Optimal pH for rapid monochloramine formation | drinking water | OG | 8.3 pH | Specific pH level where monochloramine formation occurs most rapidly. | During chloramination process | high |
| #P045 | chemical | treatment | guidance | Cl2:NH3-N weight ratio for trichloramine formation | drinking water | requirement | 15:1 weight ratio | Ratio threshold required for trichloramine formation at neutral/alkaline pH levels. | At pH 7.0 and 8.0 | high |
| Req ID | Category | Name | Context | Confidence |
|---|---|---|---|---|
| #D001 | chloramines | The term "chloramines" refers to both inorganic and organic chloramines. | high | |
| #D002 | Total chlorine | all chemical species containing chlorine in an oxidized state; usually the sum of free and combined chlorine concentrations present in water | high | |
| #D003 | Free chlorine | the amount of chlorine present in water as dissolved gas (Cl2), hypochlorous acid (HOCl), and/or hypochlorite ion (OCl-) that is not combined with ammonia or other compounds in water | high | |
| #D004 | Combined chlorine | the sum of the species resulting from the reaction of free chlorine with ammonia (NH3), including inorganic chloramines: monochloramine (NH2Cl), dichloramine (NHCl2), trichloramine (nitrogen trichloride, NCl3) and organic chloramines | high | |
| #D005 | Chlorine residual | the concentration of chlorine species present in water after the oxidant demand has been satisfied | high | |
| #D006 | Primary disinfection | the application of a disinfectant at the drinking water treatment plant, with a primary objective of achieving the necessary microbial inactivation | high | |
| #D007 | Secondary disinfection | the subsequent application of a disinfectant, either at the exit of the treatment plant or in the distribution system, with the objective of ensuring that a disinfectant residual is present throughout the distribution system | high | |
| #D008 | Cl2:NH3-N ratio by weight | The Cl2:NH3-N ratio by weight is defined as the amount of chlorine added in proportion to the amount of ammonia added (in milligrams) | high | |
| #D009 | ANSI | American National Standards Institute | high | |
| #D010 | APHA | American Public Health Association | high | |
| #D011 | bw | body weight | high | |
| #D012 | CDC | Centers for Disease Control and Prevention (United States) | high | |
| #D013 | CI | confidence interval | high | |
| #D014 | Cl2:NH3-N | chlorine:ammonia weight ratio | high | |
| #D015 | CT | concentration x time | high | |
| #D016 | DBPs | disinfection by-products | high | |
| #D017 | DPD | N,N-diethyl-p-phenylenediamine | high | |
| #D018 | EPA | Environmental Protection Agency (United States) | high | |
| #D019 | GSH | glutathione | high | |
| #D020 | HAAs | haloacetic acids | high | |
| #D021 | HOCl | hypochlorous acid | high | |
| #D022 | HPC | heterotrophic plate count | high | |
| #D023 | IARC | International Agency for Research on Cancer | high | |
| #D024 | I-DBPs | iodinated disinfection by-products | high | |
| #D025 | MDL | Method detection limit | high | |
| #D026 | MNCL | mononuclear cell leukemia | high | |
| #D027 | MRDL | maximum residual disinfectant level (United States) | high | |
| #D028 | MRDLG | maximum residual disinfectant level goal (United States) | high | |
| #D029 | NA | not available | high | |
| #D030 | NDMA | N-nitrosodimethylamine | high | |
| #D031 | NOAEL | no-observed-adverse-effect-level | high | |
| #D032 | NOM | natural organic matter | high | |
| #D033 | NSF | NSF International | high | |
| #D034 | NTP | National Toxicology Program (United States) | high | |
| #D035 | OPPPs | opportunistic premise plumbing pathogens | high | |
| #D036 | OR | odds ratio | high | |
| #D037 | T3 | triiodothyronine | high | |
| #D038 | T4 | thyroxine | high | |
| #D039 | THMs | trihalomethanes | high | |
| #D040 | WHO | World Health Organization | high | |
| #D041 | inorganic chloramines | consist of monochloramine, dichloramine and trichloramine | high | |
| #D042 | chloramination | involves the addition of ammonia (NH3) to free aqueous chlorine (hypochlorous acid, HOCl) | high | |
| #D043 | Nitrification | the microbiological process whereby ammonia is sequentially oxidized to nitrite and nitrate by ammonia-oxidizing bacteria and nitrite-oxidizing bacteria, respectively | high | |
| #D044 | CT | A measure of a chemical's efficacy as a disinfectant and is the residual concentration of a disinfectant, measured in mg/L (C) multiplied by the disinfectant contact time, measured in minutes (T). | high | |
| #D045 | organic chloramines | formed when dissolved organic nitrogen reacts with free chlorine or inorganic chloramine | high | |
| #D046 | chlorine demand | Reducers create a chlorine demand; i.e., they compete with the free chlorine added, potentially limiting the chlorine available to react with ammonia | high | |
| #D047 | RD50 | an exposure concentration producing a 50% respiratory rate decrease and an indicator of respiratory irritation | high | |
| #D048 | PVC | polyvinyl chloride | high | |
| #D049 | GAC | granular activated carbon | high | |
| #D050 | ORP | oxidation–reduction potential | high | |
| #D051 | LCR | Lead and Copper Rule | high | |
| #D052 | SCC | Standards Council of Canada | high | |
| #D053 | TSH | thyroid-stimulating hormone | high | |
| #D054 | HDL | high-density lipoprotein | high | |
| #D055 | LDL | low-density lipoprotein | high | |
| #D056 | SMR | standardized mortality ratio | high | |
| #D057 | PCAC | People Concerned about Chloramine | high | |
| #D058 | PND | postnatal day | high | |
| #D059 | MCLs | maximum contaminant levels | high | |
| #D060 | EPDM-P | ethylene propylene diene monomer-peroxide-cured | high | |
| #D061 | EPDM-S | ethylene propylene diene monomer-sulphur-cured | high | |
| #D062 | ATP | adenosine triphosphate | high | |
| #D063 | EPSs | extracellular polymeric substances | high | |
| #D064 | PAM | primary amoebic meningoencephalitis | high | |
| #D065 | SBR | styrene butadiene rubber | high | |
| #D066 | FKM | fluorocarbons | high | |
| #D067 | GGT foci | γ-glutamyl-transpeptidase foci; an indicator of carcinogenicity | high | |
| #D068 | QA/QC | quality assurance and quality control | high | |
| #D069 | Cl:N | chlorine:ammonia molar ratio | high | |
| #D070 | NH2Cl | monochloramine | high | |
| #D071 | NHCl2 | dichloramine | high | |
| #D072 | NCl3 | trichloramine | high | |
| #D073 | NH3 | ammonia | high | |
| #D074 | Chloramide | Synonym for monochloramine | high | |
| #D075 | Chlorimide | Synonym for dichloramine | high | |
| #D076 | Nitrogen trichloride | Synonym for trichloramine | high |