ISO 10651-4:2002 specifies requirements for operator-powered resuscitators intended for use with all age groups and which are portable and intended to provide lung ventilation to individuals whose breathing is inadequate. Operator-powered resuscitators for infants and children are designated according to body mass range and approximate age equivalent.ISO 10651-4:2002 is not applicable to electrically- and gas-powered resuscitators.Rationale statements are given for ISO 10651-4:2002.