Additional Deductions allowed by the Suez Canal Authority :

The SCA allows the following spaces to be included in the deductions specified in Art. 12 of the Regulations for the Measurement of Tonnage, provided the deductions do not, in the aggregate, exceed 5 percent of the gross tonnage(Maximum raised to 10% from 1st. April 1948.) . and subject to the condition that they are clearly and permanently marked so as to show the purpose to which they are exclusively appropriate:

A - Spaces for the exclusive use of officers, engineers and crew :

• Master's accommodation.
• Officer's smoking room.
• Chief engineer's and Chief officer's day rooms and/or offices.
• Doctor's and dentist's cabins (if they are occupied by the doctors and dentists for whom they are intended).
• Consulting rooms.
• Hospital.
• Infirmary.
• Surgery of operating room.
• Chemist's laboratory.
• Cabins of wireless operators (if utilized).
• Stewards cabins (if the stewards are solely employed for the officers, engineers or crew).
• Cabins of the engineers storekeepers and water tenders.
• Mess rooms. (No deduction is allowed for officers mess room in vessels having passenger accommodation which are not also provided with a passengers mess room).
• Bathrooms. (With the exception of such bathrooms as are available for passengers when no bathroom for their exclusive use is provided)
• Lavatories.
• Library.
• Bar.
• Gallery, cookhouse.
• Pantry
• Scullery,
• Bakery (only on vessels having no passenger accommodation).
• Laundry.
• Drying room.
• Heating boilers.
• Refrigerating machinery (excluding cold storage rooms and store rooms).
• Distilling apparatus.
• Disinfecting apparatus.
• Wardrobes, oilskin and lifebelt lockers.
• Ventilators (utilized neither for passengers or cargo).
• Night watchmen accommodation (provided these men are signed on as crew and are not employed in connection with passengers or cargo).
• Accommodation of fire fighting personnel.(Fire extinguishing installations are also to be deducted.)
• Domestic water pump rooms.
• Switchboard lockers.(Installations used for the needs of the crew and also for the purpose of navigation are to be treated as navigation spaces. )
• Transformer rooms.(Installations used for the needs of the crew and also for the purpose of navigation are to be treated as navigation spaces. )

B - Navigation spaces (if above the uppermost deck)

• Chart house.
• Master's spare room on the bridge (especially on warships).
• Searchlight spaces.
• Submarine telephone spaces.
• Direction finder spaces.
• Sounding spaces.
• Gyro compass spaces.
• Wireless telegraphy spaces.
• "Radar" spaces (exclusively used for navigational purposes).
• Lamp room (if only containing signal lamps)
• Lookout houses.
• Emergency generators.
• Emergency compressors (if used exclusively in case of accident for pumping out water and not for any commercial purposes).
• Switchboard lockers.
• Transformer rooms.