What this tool does
Organizes possible tests, stages, sequence and constraints while keeping uncertainty and urgent public-health escalation visible.
When to use it
Use before buying equipment and after defining the intended use. Laboratory results and local authority guidance remain the decision basis.
Inputs and supported units
Each labelled field explains the quantity it expects. Unit-system changes convert existing numeric entries once and keep calculations on a single SI internal basis. Supported shared units include L/min and GPM, metres and feet, kPa and psi, millimetres and inches, kW and hp, and °C and °F as relevant.
Calculation or decision method
Rules add only stages supported by the entered evidence, flag missing testing and preserve alternatives or constraints. A positive microbiological result triggers urgent safe-source and authority guidance rather than a universal device prescription.
How to interpret the result
Read the primary result with the supporting breakdown and warning. A plausible number is not evidence that every input, operating case or design constraint has been included.
Worked example
A private well with a laboratory report showing hardness only produces a softening review followed by monitoring. Rainwater with no laboratory test instead starts with source protection and testing, not a potable-safety claim.
Assumptions
The entered water test, flow, product concentration and manufacturer values represent the same source, use and operating condition.
Limitations
The result is a transparent preliminary calculation or decision screen. It does not establish contaminant removal, potable safety, product certification, regulatory compliance or an approved treatment design.
Sources
- U.S. EPA — Protect Your Home’s Water
- U.S. CDC — Guidelines for Testing Well Water
- U.S. CDC — About Home Water Treatment Systems
- NSF — Standards for Water Treatment Systems
- World Health Organization — Guidelines for Drinking-water Quality