ISO 16122-5:2020

Overview

ISO 16122-5:2020 - "Agricultural and forestry machines - Inspection of sprayers in use - Part 5: Aerial spray systems" defines requirements, test methods and verification procedures for inspecting manned aerial spray systems (fixed-wing and rotary aircraft) used in agriculture, forestry, turf and vegetation control. The standard focuses on minimizing the risk of environmental contamination from spray systems in sensitive areas such as transport access ways (e.g., gas and electric corridors). It addresses the condition and performance of spray equipment, not aircraft airworthiness, pilot licensing or registration, which remain subject to national regulations.

Key topics and technical requirements

The standard covers inspection scope and practical test methods - emphasizing visual and functional checks - including:

• Leak testing

  • Static leak test: tank filled to nominal capacity with pump off; visual inspection for leaks.
  • Dynamic leak test: system pressurised to maximum obtainable pressure; inspect for leaks during operation.

• Tank requirements

  • Tank surfaces free from cuts or abrasion; no loose parts.
  • Openings > 400 mm require secured bars/gratings (mesh openings ≤ 400 mm); lids tightly sealed.
  • Strainers: 20‑mesh recommended for transfer; strainers must be undamaged/unblocked.
  • Emptying devices must permit safe collection of residual liquid without environmental contamination.
  • Tank contents indicators readable from pilot/operator positions.
  • Agitation/recirculation systems must maintain an obviously disturbed liquid surface at ≥ half nominal volume.

• Hoses, lines and boom

  • Pressurised hoses marked with maximum working pressure.
  • Protective screens to prevent cockpit exposure from leaks.
  • Quick-acting shut-off valves to allow depressurization or return flow to tank.
  • Nozzle mounting, flow rate and spray quality checks; boom sectioning and nozzle orientation verification.

• Measuring and control systems

  • Validation of pressure indicators, flow-rate instruments and pressure-adjusting devices.
  • Verification of volume rate per area and pressure drop characteristics.

• Safety and inspection process

  • Inspector protection and safety procedures follow ISO 16122-1.
  • Inspection report format, test facility requirements and verification methods are specified.
  • Annex includes nozzle droplet-size resources and aerial deposition models.

Applications and users

ISO 16122-5 is used by:

• Agricultural aviation operators and contractors
• Sprayer inspection bodies and maintenance technicians
• Equipment manufacturers and OEMs of aerial spray systems
• Environmental regulators, forestry managers and utility corridor managers
• Certification and compliance auditors implementing best practices to reduce environmental contamination

Practical benefits include improved spray accuracy, reduced off-target drift, safer operations for pilots/inspectors, and documented compliance with recognized inspection methods.

Related standards

• ISO 16122-1 (General inspection requirements)
• ISO 5681 (Crop protection vocabulary)
• ISO 5682-1 and ISO 5682-2 (Nozzle and distribution test methods)

Keywords: ISO 16122-5:2020, aerial spray systems, inspection of sprayers, agricultural aviation, environmental contamination, sprayer inspection, aerial application.