ISO 17025: Laboratory Management System
The standard provides best management and technical guidance for a Testing and/or Calibration Lab. Perhaps the biggest difference between other standards and this is, a lab is not certified through a certification body but rather accredited through an accreditation body.

ISO 15189: Medical Laboratory Management System
ISO 15189 specifies requirements for quality and competence particular to medical laboratories. This standard is helpful for medical laboratories in developing their Lab Management System and assessing their own competence and for use by accreditation bodies in confirming or recognizing the competence of medical laboratories.