BS EN ISO 8504-3:2018

What is ISO 8504‑3 about?

ISO 8504 discusses the preparation of steel substrates before the application of paints and related products. ISO 8504‑3 is the third part of the ISO 8504 multi-series and discusses surface preparation methods.

The primary objective of surface preparation is to ensure the removal of deleterious matter and to obtain a surface that permits satisfactory adhesion of the priming paint to the steel. It also assists in reducing the amounts of contaminants that initiate corrosion. ISO 8504‑3 describes methods for hand- and power-tool cleaning. It should be read in conjunction with ISO 8504‑1.

Who is ISO 8504‑3 for?

ISO 8504‑3 on the preparation of steel substrates before application of paints and related products (hand- and power-tool cleaning) is useful for:

• Manufacturers of steel products
• Quality control personnel
• Painters

Why should you use ISO 8504‑3?

The performance of protective coatings of paint and related products applied to steel is significantly affected by the state of the steel surface immediately prior to painting. ISO 8504‑3 describes methods for hand-tool and power-tool cleaning of steel substrates before the application of paints and related products.

ISO 8504‑3 is applicable both to new steelwork and to steel surfaces that have been coated previously and those that show areas of a breakdown requiring maintenance painting. ISO 8504‑3  describes the equipment to be used and the procedures to be followed.

Hand- and power-tool cleaning are both suitable methods of surface preparation. Hand-tool cleaning particularly requires the use of priming paints having a good surface wetting ability. Power-tool cleaning is appropriate when a higher-quality surface preparation grade is required and when blast-cleaning is not permitted or feasible.

Power-tool cleaning will generally provide a better foundation for the priming paint than hand-tool cleaning, which results in better paint performance.

What’s changed since the last update?

BS EN ISO 8504‑3:2018 supersedes BS EN ISO 8504‑3:2001 (dual numbered as BS 7079‑D3:1993), which is withdrawn. BS EN ISO 8504‑3:2018 includes some technical changes with respect to BS EN ISO 8504‑3:2001 (dual numbered as BS 7079‑D3:1993). These include:

• Addition of rotary impact tool to types of power tools
• Replacement of inspection with assessment in Clause 6