IEC 60601-2-27:2011 applies to electrocardiographic monitoring equipments used in a hospital environment as well as when used outside the hospital environment, such as in ambulances and air transport. This particular standard also applies to ECG telemetry systems used in a hospital environment. Electrocardiographic monitoring equipments intended for use under extreme or uncontrolled environmental conditions outside the hospital environment, such as in ambulances and air transport, shall comply with this particular standard. Additional standards may apply for those environments of use. This standard is not applicable to electrocardiographic monitors for home use. However, manufacturers should consider using relevant clauses of this standard as appropriate for their intended use. Ambulatory ('Holter') monitors, fetal heart rate monitoring, pulse plethysmographic devices, and other ECG recording equipment are outside the scope of this particular standard. The aim of this third edition is to bring this particular standard up to date with reference to the third edition of the general standard through reformatting and technical changes.