Accommodation AC and Heating Regulation:

.ac regulation     .acr

MLC provides 2 regulation related to accomodtion AC

Guideline B3.1.2 – Ventilation

1. The air ventilation system for sleeping rooms and mess rooms should be controlled so that it will maintain the air in a satisfactory condition and ensure a sufficiency of air movement in all conditions of weather and climate.

2. Air-conditioning systems, whether of a centralized or individual unit type, should be designed to:

(a) maintain the air at a satisfactory temperature and relative humidity as compared to outside air conditions, ensure a sufficiency of air changes in all air-conditioned spaces and not produce excessive noises or vibrations; and

(b) arrangement for easy cleaning and disinfection should be provided to prevent or control the spread of disease

3. Power for the operation of the air conditioning available at all. However, this power need not be provided from an emergency source.

Guideline B3.1.3 – Heating

1. The system of heating the seafarer accommodation should always be in operation

2. the heating should be by means of hot water, warm air, electricity, steam or equivalent. But within the accommodation area, steam should not be used as a medium for heat transmission.

3. The heating system should be capable of maintaining the temperature in seafarer accommodation at a satisfactory level under normal conditions of weather.

3. Radiators and other heating apparatus should be shielded to avoid risk of fire or danger or discomfort to the crew.

Accommodation AC and Heating Regulation – simplified version:

Air Conditioning:

1. Ventilation System:
   • Maintain satisfactory air condition
   • Ensure sufficient air movement in all weather
2. AC System Design:
   • Maintain comfortable temperature and humidity
   • Ensure adequate air changes
   • Minimize noise and vibrations
   • Allow easy cleaning and disinfection
3. Power Supply:
   • Always available, but not required from emergency source

Heating:

      1. Operation:

1. Always in operation
2. Heating Methods:
   • Hot water, warm air, electricity, steam, or equivalent
   • Steam not allowed within accommodation area
3. Performance:
   • Maintain satisfactory temperature in normal weather
4. Safety:
   • Radiators and heating apparatus must be shielded

To help remember these regulations, focus on the following key points:

1. Comfort: Both AC and heating systems should maintain satisfactory conditions.
2. Air Quality: Ensure sufficient air movement and changes.
3. Safety: Minimize noise, vibrations, and fire risks.
4. Maintenance: Easy cleaning and disinfection for AC systems.
5. Power: AC power is always available, but not from emergency source.
6. Heating Methods: Various options, but no steam in accommodation areas.
7. Continuous Operation: Heating system always on.

Solas provides the ventilation duct requirements:

Ventilations duct – machinery space and accommodation:

SOLAS Chapter II-2, Part C: Suppression of fire: Ventilation system, Regulation 7

→ Machinery space and accommodation should have separate ventilation arrangements.

→ Ventilation ducts shall be of non-combustible material.

• Short ducts not exceeding 2 meters in length and with a cross-section not exceeding 0.02m need not be non-combustible if the following conditions are met.

(a) The dusts has a low fire risk material

(b) They may only be used at the end of the ventilation device.

(c) They shall not be situated less than 600 mm, measured along the duct, from an opening in a A or B class division including continuous B class ceilings.

(2) Where the ventilation ducts with a free- cross sectional area more than 0.02 m and not made of steel and pass through class A bulkheads or decks then the opening shall be lined with a steel sheet sleeve,

✓ in that case The ducts and sleeves shall comply with the following-

(a)The sleeves shall have a thickness of at least 3 mm and a length of at least 900 mm. When passing through bulkheads, such length shall be divided into 450mm on each side of the bulkhead. These ducts, or sleeves lining shall be provided with fire insulation. The insulation shall have at least the same fire integrity as the bulkhead or deck through which the duct passed.

(b) Ducts with a free cross-sectional area exceeding 0.075m shall be fitted with fire dampers

(C) The fire damper shall operate automatically but shall also be capable of being closed manually from both sides of the bulkhead or deck. The damper shall be provided with an indicator which shows whether the damper is open or closed. But  Fire dampers are not required, where duct pass through spaces surrounded by A class divisions, without serving those spaces. And those ducts have the same fire integrity as the divisions  through which they pierce through.

Ventilations duct – machinery space and accommodation – Simplified Version:

Main Principles

1. Machinery spaces and accommodations must have separate ventilation systems.
2. Ventilation ducts should be made of non-combustible materials.

Exceptions for Short Ducts

Short ducts (≤ 2m long, ≤ 0.02m² cross-section) can be made of combustible materials if:

1. They are made of low fire risk material
2. Used only at the end of ventilation devices
3. Located ≥ 600mm from A or B class division openings

Large Non-Steel Ducts

For ducts with > 0.02m² cross-section not made of steel, passing through A class bulkheads or decks:

1. Openings must be lined with steel sheet sleeves
2. Sleeves must be ≥ 3mm thick and ≥ 900mm long (450mm on each side of bulkhead)
3. Ducts and sleeves must have fire insulation with same integrity as the bulkhead/deck

Fire Dampers

1. Required for ducts with > 0.075m² cross-sectional area
2. Must operate automatically and manually from both sides
3. Must have an open/closed indicator
4. Not required if ducts pass through A class spaces without serving them and have same fire integrity

To help remember these regulations, focus on the key numbers:

• 2m: Maximum length for short ducts exception
• 0.02m²: Cross-sectional area threshold for special requirements
• 600mm: Minimum distance from A or B class divisions for short ducts
• 3mm: Minimum thickness for steel sheet sleeves
• 900mm: Minimum length for steel sheet sleeves
• 0.075m²: Cross-sectional area threshold for fire damper requirement