# ISO 8504

Source: https://coatmentor.com/standards/iso-8504/ · Updated 2026-10-14

Surface preparation methods for steel before painting.

**Publisher**: ISO

**Area**: Surface preparation and conditions

ISO 8504 describes the methods that clean steel before painting and what each method can achieve. It does not set the grades themselves: those are in ISO 8501.

## The parts

- **Part 1:** general principles, such as removing oil and grease before any other method.
- **Part 2:** abrasive blast cleaning, dry and wet.
- **Part 3:** hand- and power-tool cleaning.
- **Part 4:** acid pickling.
- **Part 5:** water jet cleaning, published in 2024.

## Points an inspector uses

Hand- and power-tool cleaning usually reach a lower cleanliness than blasting and do not remove oil, grease or soluble salts. Dry methods should not run in rain, and the steel should be warmer than the dew point. After preparation the surface is assessed with ISO 8501 and, where specified, tested with ISO 8502 and ISO 8503.

**5** practice items in the members area mention ISO 8504 (CIP 2: 3 · FROSIO written: 2).

## Related

- **Concepts:** [Surface cleanliness grades](https://coatmentor.com/learn/surface-cleanliness/) · [Waterjetting and flash rust](https://coatmentor.com/learn/waterjetting/)
- **Standards:** [ISO 8501](https://coatmentor.com/standards/iso-8501/) · [ISO 8502](https://coatmentor.com/standards/iso-8502/) · [ISO 8503](https://coatmentor.com/standards/iso-8503/)

## About this page

This page describes the subject of ISO 8504 in our own words; it does not reproduce the standard. For the full text, buy the current edition from ISO. Checked on 2026-10-14; errors go in the [corrections log](https://coatmentor.com/method/). CoatMentor is an independent study aid. It is not affiliated with ISO, AMPP, SSPC, NACE International, ASTM or FROSIO.