This part of ISO 9398 defines the characteristics of batch drying tumblers and gives the usual test methods for these characteristics with regard to machine capacity, power consumption and productivity. It is applicable for use as a reference in the drafting of purchasing orders for batch drying tumblers whose net usable cage volume is greater than 160 dm (litres). It does not cover safety requirements (see ISO 10472-4). NOTE If more detailed information on the effect of laundry machines on textiles is required, see ISO 7772 after agreement between the parties involved.