Overview
ISO 4444:2022 - "Agricultural sprayers - Recording of spray drift parameters" defines requirements for electronic measurement and recording of operator-controlled application parameters that influence spray drift when specified for drift reduction technologies (DRT). The standard applies to mobile sprayers for field and tree & bush crops (not hand‑held or portable sprayers) and is intended to support in-field verification of proper DRT operation.
Key topics and technical requirements
- Scope and parameters covered
- Records spray pressure (liquid and air for twin‑fluid nozzles), nozzle height (field booms), fan rotational speed (air‑assisted sprayers) and sprayer forward speed.
- Does not mandate which parameter(s) must be monitored, exact recording period length, verification procedures or data exchange formats.
- Measurement frequency
- Parameters shall be recorded as the actual measurement value every 10 s, or as an average over the last 10 s interval.
- Accuracy requirements
- Spray pressure: max error ±0.1 bar (ranges: field 0–10 bar; bush/tree up to 16 bar); air pressure for twin‑fluid nozzles 0–5 bar, ±0.1 bar.
- Nozzle height: max error ±5 % of true value (static check on flat surface); multiple points averaged.
- Fan speed: measured in r/min within ±5 % (measurement at fan drive shaft; individually for multiple fans).
- Forward speed: within ±5 % of true value (GNSS or wheel sensors acceptable).
- PRS (Parameter Registration System)
- If provided, the PRS must indicate correct functioning, start automatically with spray operation, and be incapable of manual on/off.
- Recorded values must be readable on the display with at least one decimal digit precision.
- At minimum, the last 60 minutes of operation data shall be stored and readable for at least 60 minutes after spraying ends.
- Inspection & testability
- Pressure sensors shall be accessible or have test connections for checking with reference instruments.
Practical applications and users
- Regulators and legislators designing drift‑compliance inspection schemes.
- Sprayer manufacturers and OEMs for sensor, software and data‑logging design.
- Farmers and agronomists documenting correct use of DRTs to reduce spray drift risk.
- Field inspectors and auditors verifying in‑field compliance with approved operational parameters.
- Consultants and service providers implementing precision application and record‑keeping systems.
Related standards
- ISO 16119 series (environmental requirements for sprayers) - referenced for sensor/measurement conformity.
- ISO 16119-2:2013 - cited for measurement accuracy and environmental checks.
- ISO 5681 (vocabulary) and ISO 11783-11 (data dictionary mapping) - translation table included in ISO 4444:2022.
Keywords: ISO 4444:2022, agricultural sprayers, spray drift, drift reduction technologies, DRT, parameter registration system, nozzle height, spray pressure, fan rotational speed, sprayer forward speed.