Section 1 General

101. Scope

The requirements of this chapter apply to ships intended to navigate in cold climates and may be exposed to low temperatures that may cause equipment to freeze due to ice accretion from atmos- pheric icing or sea spray, or due to freezing of liquid within a system. Protection measures are to be provided and operational procedures are to be specified to ensure that equipment is suitably pro- tected to enable operation in low temperatures.

102.

Application

1. Compliance with this chapter is optional and the requirements are additional to those subject to

the Rules for the Classification of Steel Ships.

2. Where a class notation of Ch 1 or Ch 2 or Ch

notation, the requirement of Ch 1 or Ch 2 or Ch

3. It is the responsibility of the Owner to determine particular ship's operational requirements.

3 is to be assigned in addition to Winterization

3 are to be applied additionally.

design air temperatures, are most suitable for a

4. Application of this Chapter is to be based on the lowest external design air temperature, refer to

105. This temperature does not apply to continuous operation, but is based on a distribution of op- erational time around an average temperature, assumed to be -10°C for normal worldwide operation.

Therefore, the duration of time for ship operations at temperatures below the average temperature will decrease to a minimum at the lowest temperature, and thus the operating time at the lowest

temperature is assumed to be minimal

5. Ships complying with the requirements of this Chapter may be eligible for one or more of the fol- lowing notations. Where applicable, these winterization notations are specified in below (1), (2) may be assigned one or a combination of them, e.g. Winterization E2(-35) S(A).

(1) Winterization E1(t), Winterization E2(t) or Winterization E3(t) :

Where equipment and systems are in compliance with Sec 3 in association with a lowest external design air temperature of T degrees Celsius.

(2) Winterization S(A), Winterization S(B) or Winterization S(C) :

Where stability are in compliance with Sec 4 in association with the specified ice accretion values.

(3) Winterization D(t) :

Where alternative designs, compliance with 103. in association with a lowest external design air temperature of T degrees Celsius are applied.

6. Information for selection of a suitable winterization level is given in Table 4.1. This is based on the intended operational scenarios for Winterization E1(t), Winterization E2(t) and Winterization E3(t) levels and in association with the average and lowest external design air temperatures.

7. For the assignment of Winterization E1(t), it is in subject to the requirements of this Chapter and where applicable, to be in accordance with the IMO Guidelines for Ships Operating in Arctic Ice- Covered Waters : MSC/Circ. 1056 MEPC/Circ. 399.

Table 4.1 Operational scenario for winterization requirements

103. Alternative design

1. Consideration may be given to alternative designs which do not comply with the requirements of

Sec 3 on the basis of equivalency and agreement between the Owner and Builder Shipbuilder.

2. Consideration may be given to a specification agreed by the Builder Shipbuilder and Owner for a given specific trading route based on the environmental conditions for the intended operation, e.g. temperatures and sea states, and any operational considerations, e.g. specific ship arrangements.

3.

4.

104.

1.

For ships where alternative designs are to be applied, the Winterization D(t) notation may be assigned. The lowest external design air temperature is to be included in the Winterization notation in brackets, e.g. Winterization D(-25).

The design air temperature is to be stated in association with the lowest external design air temper- ature in degrees Celsius for the assessment of hull construction materials and, equipment and sys- tems where applicable.

Information required

For Winterization levels E1(t), E2(t) and E3(t) a Winterization Manual is to be submitted. The Winterization Manual is to contain the following detailed information in order to demonstrate that the design and installation of winterization features of the ship complies with Sec 3.

(1) General arrangement highlighting winterization features and design temperatures.

(2) List of winterization equipment and systems.

(3) Details of tank heating, refer to 302.

(4) Details of design internal ambient temperatures for accommodation heating/air conditioning systems, refer to 303. 1.

(5) Details of heating arrangements for spaces, refer to 303. 2, 303. 3.

(6) Trim and stability conditions.

(7) Inventory and locations of ice removal measures, refer to 305.

(8) Details of accommodation and escape route arrangements, refer to 304.

(9) Details of anchoring/mooring and deck crane arrangements, refer to 306.

(10) Details of main/auxiliary engines arrangements, see 308 and 309.

(11) Details of materials specification/heating arrangements for exposed pipework/components, refer to 309.

(12) Details of materials specification/heating arrangements for exposed electrical cables/components,

refer to 310.

(13) Details of winterization of emergency appliances, refer to 311.

(14) Details of operational and maintenance procedures e.g.

• Continuous circulation of fluids and/or heating media.

• Use of heating arrangements in sub-zero temperatures.

• Application of silicone spray or other suitable low temperature films to door/hatch seals.

• Application of low temperature lubricants.

• Use of antifreeze in liquid filled pressure/vacuum breakers in inert gas lines on tankers.

• Use of antifreeze in emergency generators and lifeboat /rescue boat engines.

• Use of oil fuel for emergency generators and lifeboat /rescue boat engines that is suitable for

low temperature conditions.

• Use of low temperature grease for lifeboat/rescue boat davits/sheaves/release hooks and for

radar motors.

• Use of suitable antifreeze solutions for bridge window cleaning.

• Steam heating coil condensate evacuation (draining) if and when heating coils are redundant.

2. For Winterization S(A), S(B) and S(C), details of the trim and stability conditions, and calculations, are to be submitted in order to demonstrate that the design of the ship complies with Sec 4.

3. Where an alternative design is used for Winterization D(t), as described in 103, the Winterization Manual is to be submitted based on an agreed specification list confirmed by the Builder Shipbuilder and Owner with reference to the intended operation, ship type and arrangement.

4. Details of the average design external air temperature, lowest design external temperature and de- sign internal air temperature/ambient conditions for spaces within the ship are to be agreed with the Owner and Builder and submitted Shipbuilder. These details are to include machinery spaces, habit- able spaces, those commonly accessed and any other spaces where the temperature will differ. Temperatures are to be rounded down to the nearest integer, e.g. -21.5°C is to be -22°C.

5. A copy of the Winterization Manual is to be placed on board the ship.

105.

Definitions

1. Average external design air temperature

The average external design ait temperature is to be taken temperature in the area of operation :

as the lowest mean daily average air

Where Mean Average Lowest MDHT MDAT MDLT

= statistical mean over a minimum of 20 years

= average during one day and one night

= lowest during the year

= Mean Daily High Temperature

= Mean Daily Average Temperature

= Mean Daily Low Temperature

Fig 4.1 Average external design air temperature

2. Lowest external design air temperature

The lowest external design air temperature is to be taken as the lowest mean daily lowest air tem- perature in the area of operation. Where reliable environmental records for contemplated operational areas exist, the lowest external design air temperature may be obtained after the exclusions of all recorded values having a probability of occurrence of less than 3 per cent. In general and unless otherwise specified, the lowest external design air temperature, Ty, may be taken as the average external design air temperature, Tx, minus twenty degrees Celcius (Ty = Tx - 20), or vice versa (Tx = Ty + 20). For example: Tx = -25 and Ty = -45.

3. Design internal air temperature / ambient conditions

The design parameters for the heating systems for accommodation and heated spaces(to be defined for each individual space). See 104. 4.

4. Covers

Materials and arrangements used to protect items or equipment. These may be fixed type, such as mild steel, or removable, such as PVC coated nylon or other water-resistant material and are to completely cover the item of equipment without impairing its function.

5. Heating arrangements

Equipment and systems used to provide heat by means of electrical, steam, oil or other means

6. Ice removal measures

Ship services or tools used to facilitate the removal of ice by means of steam, hot water or hot air, manual tools, de-icing compounds or other means.

7. Protected locations

Location behind walls, screens, bulkheads and equipment, located inboard and recessed, onboard the ship and providing protection from icing.