Sudden ice accretion can quickly cover a ship’s superstructures, weather decks, and deck machinery, catching crews off guard. This buildup of ice makes hatch covers and machinery unusable until it’s cleared away. Since de-icing is a tedious and time-consuming process, ships must be equipped to handle the task efficiently. Reducing ice accumulation and preparing vessels for de-icing are critical steps to ensure safe and effective operations.
TYPES OF ICE ACCRETION AND RISKS
Freshwater ice accretion – This type of ice can form from fog, drizzle, rain or snow. Freshwater ice accumulation may be smaller in quantity compared to seawater ice accretion; however, it can cause radar, aerial and insulator failures. This icing also creates hazards for personnel on deck, both from slip potential and ice falling from accumulations on rigging and stays.
Seawater ice accretion – Seawater icing occurs when cold sea spray comes into contact with exposed surfaces, and the air temperature is below freezing. Seawater ice accretion is influenced by two main factors: environmental conditions and ship characteristics. Environmental conditions, such as wind speeds above Beaufort Wind Scale 5, ambient air temperatures below -2°C, and seawater temperatures below 4°C, are ideal for seawater ice accretion. Ship characteristics, such as speed, heading relative to wind, waves, and swell, exposed surface area, length, and freeboard, all contribute to ice accretion.
Seawater ice accretion can impact the stability of the ship especially small ships. Severe ice accretion can cause commercial losses due to time lost or missed berthing slots, as cargo gear and mooring equipment may become inoperable.
Full advisory at the following link.
https://britanniapandi.com/wp-content/uploads/2024/10/Ice-accretion-in-winter-conditions.pdf