ISO 22282-5:2012

Overview

ISO 22282-5:2012 - "Geotechnical investigation and testing - Geohydraulic testing - Part 5: Infiltrometer tests" defines how to perform in situ infiltrometer tests to determine the water permeability and infiltration capacity of soils and treated/compacted materials. The standard is part of the ISO 22282 geohydraulic testing series and is intended for geotechnical investigations carried out in accordance with EN 1997‑1 and EN 1997‑2.

Key topics and technical requirements

• Purpose: Determine infiltration capacity and calculate the permeability coefficient (k) under steady‑state (constant‑head) or transient (variable‑head) conditions in saturated or unsaturated soils.
• Test types: Open systems (single or double‑ring infiltrometers) and closed systems (sealed single‑ring with lid and pressure control).
• Equipment:
  • Test cell (ring geometry), measuring device for hydraulic head or infiltrated volume, installation tools, optional pump and insulation.
  • Minimum ring diameter and installation depth requirements (rings typically ≥ 200 mm diameter; penetration depth ≥ 50 mm).
  • Measurement resolutions and controls: volume/pressure controller with fine resolution (e.g., 0.1 ml for constant‑head closed systems), hydraulic head measurement uncertainty ~1 mm for variable‑head, and temperature sensor resolution (≥ 0.5 °C) when viscosity corrections are needed.
  • Use of clean, suspended‑solid‑free water and appropriate sealing materials.
• Procedures:
  • Surface preparation, ring installation (pushing, hammering, or excavated slot), saturation phase, followed by constant‑head or variable‑head testing.
  • Observations for lateral leakage and criteria for terminating/repeating tests if leaks occur.
  • Data logging of time, infiltrated volume, hydraulic head and temperature; graphical presentation of results.
• Results & reporting:
  • Constant‑head: infiltrated volume vs time, surface flow rate, and permeability coefficient.
  • Variable‑head: hydraulic head vs time and permeability coefficient from water‑level decline.
  • Mandatory field and test reports including raw data, apparatus description, test conditions, corrections, graphical plots, and signatures.

Practical applications and users

ISO 22282-5 is applied in:

• Civil engineering site investigations (foundations, drainage design)
• Hydrogeology studies (infiltration and recharge assessment)
• Waste disposal and storage facility design (leakage and containment assessment)

Typical users include geotechnical engineers, hydrogeologists, environmental engineers, field testing contractors, and laboratory specialists involved in permeability and infiltration assessment.

Related standards

• ISO 22282 series (Parts 1–6) - geohydraulic testing framework
• ISO 22282‑1 (General rules)
• ISO 22475‑1 (Sampling methods and groundwater measurements)
• EN 1997‑1 / EN 1997‑2 (Geotechnical design and investigation standards)

Keywords: ISO 22282-5, infiltrometer tests, geohydraulic testing, water permeability, permeability coefficient, in situ testing, open ring infiltrometer, closed ring infiltrometer, geotechnical investigation.