ISO 23333:2025

Overview

ISO 23333:2025 - Natural gas - Upstream area - Requirements and testing of slick water is an international standard that defines performance, sampling, testing, inspection and documentation for slick water fracturing fluids used in hydraulic fracturing for shale gas. It provides harmonized technical criteria to support producers, suppliers, service companies, testing laboratories and regulators in ensuring consistent quality and safe use of slick water in upstream natural gas operations.

Key Topics and Requirements

The standard sets clear, testable requirements and references established test methods:

• Scope: Applicable to fracturing fluid systems used in hydraulic fracturing operations in shale gas.
• Performance limits:
  • pH: 6.0 to 9.0.
  • Residue content: ≤ 150 mg/l.
  • Drag reduction: ≥ 60% (measured per ISO 7055).
  • Dissolution time: additives dissolve within 40 s.
  • Kinematic viscosity: < 5.0 mm²/s (tested per ISO 3104).
• Compatibility: No precipitation or flocculation under room and reservoir test conditions (detailed method in Annex A).
• Sampling:
  • Laboratory: at least three replicate samples per batch.
  • Field: continuous-mix samples every 5 minutes, minimum three samples; quartering method for reduction.
  • Sample retention: split into two containers; retain reference sample up to 3 months; testing preferably within 24 h.
• Testing methods:
  • pH per ISO 13503-3.
  • Drag reduction per ISO 7055.
  • Residue content and dissolution time per Annexes B and C.
  • Kinematic viscosity per ISO 3104.
• Inspection & acceptance:
  • Full-item inspection for laboratory samples; field inspections must include pH, compatibility and kinematic viscosity.
  • Re-inspection rules if initial tests fail.
• Accompanying documents: product qualification certificate, quality inspection report, Material Safety Data Sheet (MSDS).

Applications and Users

ISO 23333:2025 is practical for:

• Shale gas producers and well operators setting procurement and acceptance criteria for slick water.
• Chemical suppliers and service companies developing or supplying fracturing fluids.
• Third‑party testing laboratories performing QA/QC and compliance testing.
• Regulators and project owners establishing contract specifications and environmental/operational controls.
• Use cases include on-site quality control during hydraulic fracturing, product certification, dispute resolution, and international trade of slick water products.

Related standards

Relevant cross-referenced standards include:

• ISO 7055 - Drag reduction determination for slick water
• ISO 3104 - Kinematic viscosity testing
• ISO 13503-3 - pH and completion fluids testing
• ISO 3170 - Manual sampling of hydrocarbon liquids
• ISO 14532 - Natural gas vocabulary

Keywords: ISO 23333:2025, slick water, hydraulic fracturing, shale gas, drag reduction, fracking fluid testing, compatibility testing, residue content, kinematic viscosity, sampling and testing, upstream natural gas.