Overview
ISO 15873:2002 specifies requirements for differential pressure Venturi-type liquid additive injectors used in irrigation systems. It covers construction, operational requirements and test methods for injectors that meter and mix liquid additives (liquid fertilizers, acids, alkalis, pesticides, herbicides and other solutions) into motive irrigation water. The standard does not cover backflow prevention to potable supplies - that is addressed by local water protection regulations.
Key topics and technical requirements
- Scope & definitions: Clear terminology for motive water, injection rate, injection ratio, pressure differential, maximum working pressure and nominal size.
- Classification of installations: In-line, by-pass, by-pass around pressure-reducing valve, and side-stream (booster pump) mountings.
- Markings: Injectors must bear durable markings including manufacturer name/trademark, model number, flow direction arrows, nominal size/thread form, and a date code.
- Materials & durability: Parts in contact with water/additives must resist chemical attack; surfaces exposed to UV must be UV-stabilized.
- Threading: Threads per ISO 7‑1 or supplied adapters for alternative threads.
- Mechanical tests:
- Static pressure test at 3× maximum working pressure for 60 min (no leakage, fracture, deformation).
- Temperature resistance at 66 °C ± 2 °C under maximum working pressure for 5 min.
- Negative pressure test at 90.0 kPa (gauge) for 5 min.
- Functional tests:
- Performed with water at 23 °C ± 2 °C, filtered per manufacturer guidance.
- Motive fluid testing at ≥5 inlet pressures spanning manufacturer’s minimum and maximum; measure injected flow at 20%, 40%, 60%, 80% and 100% percent pressure differentials.
- Injected flow must be ≥ 90% of manufacturer-declared flow under same conditions.
- Initiation pressure differential must be within ±5% of the manufacturer’s declared value.
- Sampling & acceptance: Sampling per ISO 2859‑1:1999 (AQL 2.5, inspection level S‑4); instrumentation accuracy recommended to ±1%.
Applications and users
ISO 15873 is intended for:
- Manufacturers of Venturi-type fertilizer/chemical injectors (design, construction, marking, performance data).
- Test laboratories and QA teams conducting mechanical and functional conformity tests.
- Irrigation system designers and integrators specifying injectors for agricultural, horticultural and turf irrigation systems.
- Regulators and procurement professionals referencing safety, performance and documentation requirements.
Practical applications include fertilizer injection, pH control (acids/alkalis), and pesticide/herbicide dosing in drip, sprinkler and pivot irrigation systems.
Related standards
- ISO 7‑1 - Pipe threads where pressure‑tight joints are made on the threads.
- ISO 2859‑1:1999 - Sampling procedures for inspection by attributes (AQL procedures).
- Local water protection and backflow prevention regulations (for potable supply protection).