This International Standard specifies general requirements for laryngoscopes and critical dimensions for the handle and lamp of hook-on type laryngoscopes. It is applicable only to instruments with an electrical power source for illuminating the larynx, since electrical safety requirements may be more stringent for instruments connected to mains or external power packs. This International Standard is not applicable to surgical instruments known by the same generic name. This International Standard does not apply to: a) the blade form or handle design, except for general requirements and the interchangeability aspects of the connection between the blade and the handle; b) the measurement and specification of the lamp illumination intensity; c) flexible laryngoscopes, or laryngoscopes designed for surgery; d) laryngoscopes powered from mains electricity supply; e) laryngoscopes connected by light-transmitting cables to external light sources. NOTE Instruments connected by light guides to an external light source may be subject to other International Standards for endoscopes.