ISO-8862-1987.pdf

Foreword IS0 (the International Organization for Standardization) is a worldwide federation of national standards bodies (IS0 member bodies). The work of preparing International Standards is normally carried out through IS0 technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, govern- mental and non-governmental, in liaison with ISO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the IS0 Council. They are approved in accordance with IS0 procedures requiring at least 75 % approval by the member bodies voting. International Standard IS0 8862 was prepared by Technical Committee ISO/TC 8, Shipbuilding and marine structures. Users should note that all International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its latest edition, unless otherwise stated. International Organization for Standardization, 1987 Printed in Switzerland -,-,- INTERNATIONAL STANDARD IS0 8862 : 1987 (E) Air-conditioning and ventilation of machinery control-rooms on board ships - Design conditions and basis of calculations 0 introduction 4 Design conditions This International Standard is fundamentally based on IS0 7547, which is required to apply this International Stan- dard. 4.1 General The system shall be designed for conditions as follows : Outdoor air : + 35 OC and 70 % relative humidity Indoor air : + 27 OC Engine room air : + 45 OC NOTE - All temperatures stated are dry bulb temperatures. 1 Scope and field of application This International Standard specifies design conditions and suitable methods of calculation for air-conditioning and ventila- tion of the machinery control-room on board seagoing mer- chant ships for all conditions except those encountered in ex- tremely cold or hot climates (i.e. with a lower or higher en- thalpy than that stated in 4.1). Applicable parts of the Standard can be used for similar spaces such as the control-room for pro- pulsion machinery. The annex provides guidance and details of good practice in the design of ventilation and air-conditioning systems for machinery control-rooms 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. 2 References I S 0 7547, Air-conditioning and ventilation of accommodation spaces on board ships - Design conditions and basis of calculations. IEC Publication 92, Electrical installations in ships - Part 101 : Definitions and general requirements. Part 504 : Special features - Control and instrumentation. 3 Definitions For the purposes of this International Standard;the definition given below, together with those in IS0 7547, apply : machinery control-room : Space containing the system of the main alarm displays and controls for the propulsion machinery. 4.2 Occupancy The number of persons to be allowed for in the machinery control-room shall be 3, unless otherwise stated by the pur- chaser. 5 Calculation of heat gains 5.1 Applicability For the calculation of far as it is applicable), apply l heat transmission and solar heat gain (as subclauses 5.2 and 5.3 of IS0 7547 shall Heat losses shall not be taken into account. NOTE - Any required additional heating during winter is assumed to be carried out by separate means of heating, other than by air supply, unless otherwise specified by the purchaser. In addition to values for the total heat transfer coefficients given in table 2 in IS0 7547, the values given in the table below shall be used where appropriate, unless otherwise specified by the purchaser. Table - Total heat transfer coefficients I Surfaces Total heat transfer coefficient, k W/(mz.K) I I Control-room bulkhead and ceiling against engine room 03 I I Control room floor against engine room 12 I I Window, triple glazing I 23 I Is0 8862 : 1987 E) 5.2 Heat gain from persons Values of sensible and latent heat emitted by a person shall be in accordance with subclause 5.4 in IS0 7547 (Activity : seated at rest). 5.3 Heat gain from lighting and other sources Heat gain from general lighting shall be taken as 10 W/m* unless otherwise specified by the purchaser. In addition, the heat gain from appliances shall be taken as the value at which the appliance generates sensible heat under nor- mal use at the time of peak cooling load. The purchaser shall give information about the maximum simultaneous and continuous heat gain in kilowatts from each group of electrical equipment and the location of this equip- ment. Where the heat gain from the equipment is not specified by the purchaser, it shall be taken as 7 kW. NOTE - It is assumed that the electrical equipment is designed ac- cording to IEC Publications 92-101 and 92-504 as regards environmen- tal conditions (temperature, humidity, etc. 1. 6 Airflow calculation 6.1 Volume of space Volume of consoles, cabinets, furniture, stationary equipment, etc. shall not be deducted in calculating the gross volume of the control-room. 6.2 Supply airflow The air supply to the control-room shall be calculated using whichever of the following criteria gives the highest value : a) airflow to maintain the conditions of 4. I; b) outdoor supply airflow not less than 0,008 m3/s per person. 6.3 Temperature of supply airflow Wherever relevant, subclause 6.3 in IS0 7547 shall apply. 6.4 Air balance The system shall provide a positive pressure in the room. Annex Guidance and good practice (This annex does not form an integral part of the Standard.) A.1 General Guidance and good practice according to annex A of IS0 7547 is recommended to be applicable wherever relevant. A.2 Airflow through electrical cabinets Air distribution to be arranged to allow an airflow through electrical cabinets according to manufacturers requirements. UDC 629.12.011.56 : 629.1.06 Descriptors : shipbuilding, ships, machinery control rooms, air conditioning, ventilation, specifications. Price based on 2 pages 2 -,-,-