3 Definitions
Clasification Society 2024 - Version 9.40
Statutory Documents - IMO Publications and Documents - Circulars - Maritime Safety Committee - MSC.1/Circular.1321 – Guidelines for Measures to Prevent Fires in Engine-Rooms and Cargo Pump-Rooms – (11 June 2009) - Annex – Guidelines for Measures to Prevent Fire in Engine-Rooms and cargo Pump-Rooms - Part 1 – General - 3 Definitions

3 Definitions

  3.1 Flashpoint means the temperature in degrees Celsius (closed cup test) at which a product will give off enough flammable vapour to be ignited, as determined by an approved flashpoint apparatus.

  3.2 Auto-ignition point means the temperature at which a substance will spontaneously combine with oxygen and burn without an external ignition or heat source.

  3.3 High temperature surfaces means surfaces with temperatures above 220°C.

  3.4 Hot surfaces means surfaces with a temperature of less than 220°C including steam systems with a pressure of less than 2.3 N/mm2, thermal oil systems, exhaust gas piping and oilfired and exhaust gas boilers.

  3.5 Heated surfaces means surfaces with a high temperature source on the other side.

  3.6 Potential ignition sources means sources having enough energy to cause ignition. These include high temperature surfaces, sparks or flames from inefficient flanges or joints, electrical discharges caused from electrostatic atmospheres, or electrical contactor faults. Sources of these are for example exhaust gas piping of internal combustion engines, leakages from boiler furnace joints and electrical equipment within oil treatment rooms.

  3.7 Flammable oils, for the purpose of these Guidelines, means those oils used in machinery spaces such as those listed in table 1.

  3.8 Flammable oil system means the system used for the supply of flammable liquid to engines or equipment.

  3.9 Lower flammable limit (LFL) means the concentration of a hydrocarbon gas in air below which there is insufficient hydrocarbon to support and propagate combustion.


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