Legal & Engineering Terms

Terms of Use & Professional Engineering Disclaimer

By accessing or using the calculators, formulas, articles, and data tables on PSI to GPM, you acknowledge and agree to the terms, limitations, and engineering disclaimers detailed below.

1. Educational and preliminary scoping scope only

All calculations, algorithms, lookup tables, and technical documentation published on this website are provided strictly for general educational reference, conceptual design scoping, and preliminary field estimation. They do not constitute formal engineering advice, architectural plans, certified hydraulic calculations, or construction submittals.

2. Life-safety and critical infrastructure exclusion

This website must not be relied upon as the sole basis for designing, constructing, commissioning, or inspecting life-safety, fire protection, or high-hazard pressure systems, including but not limited to:

• Automatic fire sprinkler networks governed by NFPA 13
• Standpipe and hose systems governed by NFPA 14
• Stationary fire pump installations governed by NFPA 20
• Municipal potable water distribution and fire flow infrastructure governed by AWWA standards
• High-pressure industrial steam, chemical, or compressed gas lines governed by ASME B31

Any system affecting life safety, structural integrity, public health, or building code compliance must be designed, modeled, and stamped by a licensed Professional Engineer (PE) and reviewed by the local Authority Having Jurisdiction (AHJ).

3. Boundary conditions and physical assumptions

Unless explicitly configured otherwise by user input, all calculators assume:

• Fluid Properties: Pure, single-phase liquid water at standard ambient conditions (60°F / 15.6°C, density ρ ≈ 62.4 lb/ft³, kinematic viscosity ν ≈ 1.217 × 10⁻⁵ ft²/s). Fluid density and viscosity variations due to elevated temperatures, glycol solutions, slurries, or aeration are not accounted for unless specified.
• Steady-State Flow: All formulas evaluate steady, non-pulsating, continuous flow. Transient dynamic phenomena—including water hammer, hydraulic shock waves, cavitation collapse, and column separation—require specialized surge analysis.
• Pipe Dimensions and Roughness: Calculations utilize nominal wall schedules (e.g., ASTM Schedule 40/80 PVC, ASTM B88 Copper Types K/L/M) and typical Hazen-Williams C-factors or absolute roughness (ε) values. Actual field piping may exhibit wall thinning, internal biofouling, tuberculation, or manufacturing tolerances that substantially alter hydraulic resistance.

4. Limitation of liability

PSI to GPM, its authors, editors, and contributors make no representations or warranties of any kind, express or implied, regarding the accuracy, completeness, reliability, suitability, or operational availability of the tools and information provided. In no event shall PSI to GPM or its contributors be liable for any direct, indirect, incidental, consequential, special, or exemplary damages—including equipment damage, pipe failure, property loss, business interruption, or personal injury—arising out of or in connection with the use or inability to use this site or reliance on its calculation outputs.

5. Acceptable use & intellectual property

You may use our calculators for personal and internal professional engineering work. You may not scrape, frame, mirror, or repackage our calculation engines, text content, or UI tools into competing commercial tools or services without prior written permission.

6. Revisions, errata and updates

We reserve the right to revise formulas, documentation, and these terms at any time to reflect revised engineering standards or mathematical corrections. All revisions are logged publicly in our Calculation Errata & Updates Log. Continued use of the site following published modifications constitutes acceptance of the revised terms.

7. Governing law and dispute resolution

These terms and any dispute, controversy, or claim arising out of or relating to the use of this website, its calculators, or services shall be governed by and construed in accordance with the laws of the applicable operating jurisdiction, without giving effect to any principles of conflicts of law. Users agree that any formal dispute resolution proceedings shall be submitted to the competent courts of the operating jurisdiction.