This International Standard specifies design conditions and suitable methods of calculation for air-conditioning and ventilation of the wheelhouse on board seagoing merchant ships for all conditions except those encountered in extremely cold or hot climates (i.e. with a lower or higher enthalpy than that stated in 4.1). It applies to a wheelhouse supplied with air-conditioning and ventilation either by the general accommodation system or by its own individual system. The annex provides guidance and details of good practice in the design of ventilation and air-conditioning systems for the wheelhouse in ships. NOTE — Users of this International Standard should note that, while observing the requirements of the Standard, they should at the same time ensure compliance with such statutory requirements, rules and regulations as may be applicable to the individual ship concerned.