Why does ISO 6330 mention 2 spin speeds?

The standard ISO 6330 defines apparatus and test materials, and specifies standardized washing and drying procedures for dimensional stability and appearance in textiles testing.

Most people in the textile testing sector are familiar with ISO 6330 Textiles – Domestic washing and drying procedures for textile testing.

It contains many options for choosing the appropriate washing and drying procedures.

Annex A – Specification for reference washing machine Type A specifies that the drum speed must be capable of achieving 500rpm (low spin) and 800rpm (high spin).

However, for all procedures contained within this standard, the spin speed is 500rpm.