ASTM F22-21 PDF

Full title and description

ASTM F22-21 — Standard Test Method for Hydrophobic Surface Films by the Water‑Break Test. This ASTM test method describes a rapid, nondestructive qualitative procedure to detect hydrophobic (nonwetting) films on surfaces or hydrophobic organic contamination in processing environments by observing the continuity (or “break”) of water on a surface when it is withdrawn from or doused with water.

Abstract

F22‑21 specifies the water‑break inspection technique used as a go/no‑go check for the presence of molecular or thicker hydrophobic films on substrates. The method is intended for quick process control and environmental monitoring where a simple verification of surface wettability (water‑break free vs. water‑break) is sufficient. It is not a quantitative contact‑angle measurement but is complementary to contact‑angle and other quantitative wetting methods.

General information

• Status: Active / published
• Publication date: December 1, 2021 (current edition approved Dec 1, 2021)
• Publisher: ASTM International
• ICS / categories: 25.220.20 — Surface treatment
• Edition / version: F22‑21 (2021)
• Number of pages: 5 (short test method)

Scope

This test method covers the detection of hydrophobic (nonwetting) films on surfaces and the presence of hydrophobic organic materials in processing environments using the water‑break technique. When properly conducted the test can detect molecular layers of hydrophobic organic contaminants; sensitivity is reduced on very rough or highly porous surfaces. The method is intended for applications where qualitative, rapid go/no‑go evaluation of surface wettability or cleanliness is required and where immersion or dousing with water is practical.

Key topics and requirements

• Principle of the water‑break test: observe continuity or breakage of a film of water on a surface removed from or doused with purified water.
• Test preparation: cleaning/conditioning of specimen, use of appropriate purified water, vertical withdrawal or dousing technique.
• Interpretation: criteria for “water‑break free” (continuous film) versus presence of hydrophobic films (breaks, beading, or discontinuities).
• Limitations: qualitative method only; sensitivity affected by surface roughness, porosity, and test liquid purity.
• Comparisons and complements: guidance when to use quantitative contact‑angle methods instead (e.g., Test Methods C813, D5946, D7490 or Practice D7334).
• Recommended uses: in‑process verification, environmental witness surface monitoring, and pre‑treatment inspections prior to priming, plating, anodizing or adhesive bonding.

Typical use and users

Used by quality control and process engineers, surface treatment and finishing shops, coatings and adhesive manufacturers, plating and anodizing facilities, aerospace and defense contamination control teams, and laboratory technicians who need a fast, nondestructive check for hydrophobic contamination before downstream processing. Also used for environmental monitoring with witness coupons to detect airborne hydrophobic contaminants.

Related standards

Commonly referenced or complementary standards and practices include ASTM F21 (Atomizer Test for hydrophobic films), ASTM C813, ASTM D5946, ASTM D7490 and ASTM D7334 (contact‑angle and wettability measurement methods), and other ASTM practices for surface cleanliness and wetting tension. The standard sits with other contamination and surface‑wettability test methods maintained by ASTM technical committees dealing with contamination control and surface treatment.

Keywords

water‑break test, hydrophobic film, surface contamination, wettability, contact angle (qualitative), surface cleanliness, contamination control, witness coupon, ASTM F22‑21

FAQ

Q: What is this standard?

A: ASTM F22‑21 is a short test method that defines the water‑break inspection procedure to detect hydrophobic surface films or hydrophobic organic contamination by observing whether a continuous film of water breaks (beads) on withdrawal or dousing.

Q: What does it cover?

A: It covers the qualitative detection and interpretation of hydrophobic films on surfaces and the use of witness surfaces for environmental monitoring. It explains test technique, limitations, and situations where quantitative contact‑angle methods should be used instead.

Q: Who typically uses it?

A: Quality/control technicians, surface‑treatment and finishing operations, coating and adhesive formulators, plating and anodizing shops, aerospace contamination control groups, and laboratories performing pre‑treatment cleanliness checks.

Q: Is it current or superseded?

A: The current edition is F22‑21, approved December 1, 2021. As of February 22, 2026 this edition is active and is the applicable version for the water‑break test unless a later revision has been published after that date.

Q: Is it part of a series?

A: It is one of several ASTM test methods addressing hydrophobic surface films and wettability. Closely related methods include ASTM F21 (Atomizer Test) and several quantitative contact‑angle and wettability practices and test methods (for example C813, D5946, D7490, D7334).

Q: What are the key keywords?

A: Hydrophobic, water‑break, surface film, contamination, wettability, contact angle, cleanliness, witness coupon, process control.