Survey Of Drinking Water Treatment Devices - Available On The Canadian Retail Market In 1999

Appendix C - NSF International Standards for Drinking Water Treatment Devices

ANSI/NSF Standard 42: Drinking Water Treatment Units - Aesthetic Effects

The point-of-use and point-of-entry systems addressed by this standard are designed to be used for the reduction of specific substances that may be present in drinking water (public or private) considered to be micro biologically safe and of known quality. Systems covered under this standard are intended to reduce substances affecting the aesthetic quality of the water or to add chemicals for scale control, or both. Substances may be soluble or particulate in nature at levels influencing public acceptance of the drinking water. It is recognized that a system may be effective in controlling one or more of these substances but is not required to control all. Systems with components or functions covered under other NSF or ANSI/NSF standards or criteria shall comply with those applicable requirements.

ANSI/NSF Standard 44: Residential Cation Exchange Water Softeners

The manual, auto-initiated, and demand-initiated regeneration residential cation exchange water softeners addressed by this standard are designed to be used for the removal of hardness and the reduction of specific contaminants from drinking water supplies (public or private) considered to be micro biologically safe and of known quality. Systems with components or functions covered under other NSF, ANSI/NSF Standards or criteria shall comply with those applicable requirements.

ANSI/NSF Standard 53: Drinking Water Treatment Units - Health Effects

The point-of-use and systems addressed by this standard are designed to be used for the reduction of specific substances that may be present in drinking water (public or private). These substances are considered established or potential health hazards. They may be microbiological, chemical, or particulate (including filterable cysts) in nature. It is recognized that a system may be effective in controlling one or more of these contaminants, but it is not required to control all. Activated carbon filter systems covered by this standard are not intended to be used with water that is micro biologically unsafe or of unknown quality without adequate disinfection before or after the system. This standard establishes requirements for point-of-use drinking water treatment systems, and the materials and components used in these systems. It also establishes requirements for point-of-entry drinking water treatment systems used to treat all or part of the water at the inlet to a residential facility or a bottled water production facility and the materials and components used in these systems.

ANSI/NSF Standard 55: Ultraviolet Microbiological Water Treatment Systems

This standard covers ultraviolet (UV) microbiological water treatment systems and components for point-of-use and point-of-entry applications. Systems are intended to be used under the following specific conditions:

Class A Systems - Class A point-of-entry and point-of-use systems covered by this standard are designed to disinfect and/or remove microorganisms from contaminated water, including bacteria and viruses, to a safe level. Systems covered by this standard are not intended for the treatment of water that has an obvious contamination source, such as raw sewage; nor are systems intended to convert wastewater to micro biologically safe drinking water. The systems are intended to be installed on visually clear water (not coloured, cloudy, or turbid). Systems intended for treatment of surface waters will need to be installed downstream of a prefilter tested for cyst reduction in compliance with ANSI/NSF Standard 53: Drinking Water Treatment Units - Health Effects.

Class B Systems or Components - Class B point-of-use systems covered by this standard are designed for supplemental bactericidal treatment of treated and disinfected public drinking water or other drinking water which has been tested and deemed acceptable for human consumption by the state or local health agency having jurisdiction. The system is designed to reduce normally occurring non-pathogenic or nuisance microorganisms only. The Class B system is not intended for the disinfection of microbiologically unsafe water.

ANSI/NSF Standard 58: Reverse Osmosis - Drinking Water Treatment Systems

The point-of-use reverse osmosis drinking water treatment systems addressed by this standard are designed to be used for the reduction of specific substances that may be present in drinking water supplies (public or private) considered to be micro biologically safe and of known quality (except that claims for the reduction of filterable cysts may be permitted). Systems covered by this standard are intended for reduction of total dissolved solids (TDS) and other contaminants specified herein. Systems with components or functions covered under other NSF, or ANSI/NSF Standards or criteria shall comply with those applicable requirements.

ANSI/NSF Standard 62: Drinking Water Distillation Systems

Distillation systems covered by this standard are systems designed to be used to reduce specific chemical contaminants as specified herein from public or private drinking water supplies. Systems designed to reduce microbiological contaminants from public or private water supplies are also covered under this standard. Systems covered by this standard are not intended for the treatment of water that is visually contaminated (turbid) or has an obvious contamination source, such as raw sewage; nor are systems intended to convert wastewater to micro biologically potable water. This standard establishes minimum requirements for point-of-use and point-of-entry drinking water distillation systems and materials and components used in these systems.

Acknowledgement: Most of the above information is taken from NSF International documents.