ISO 9588:2007 specifies procedures for reducing susceptibility, or degree of susceptibility, to hydrogen embrittlement that can arise in surface finishing processes. The heat-treatment procedures for iron or steel specified in ISO 9588:2007 have been shown to be effective in reducing the susceptibility to hydrogen embrittlement. These heat-treatment procedures are used after surface finishing, but prior to any secondary conversion-coating operation. Stress-relief heat-treatment procedures applied after fabrication, but prior to surface finishing, are specified in ISO 9587. ISO 9588:2007 does not apply to fasteners.