Comfort class notation addressing indoor climate.
Purpose
The class notation confirms that the vessel is verified to comply with environmental standards for indoor climate (C) influencing the well-being of crew and passengers. Compliance with the rules is to be verified
through measurements of defined environmental parameters.
Benefits
The comfort on board is an important quality of the vessel. High comfort increases the performance and vigilance of the crew and consequently the safety of ship and cargo. For a passenger ship, the comfort will be significant for the rating and reputation in the market. Indoor climate is in this respect a significant parameter. A specified climate comfort of a room signifies that the majority of the passengers and crew can safely and comfortably perform an activity there over a prolonged period of time.
DNV was the first classification society to issue comfort standard on indoor climate. Today more than 250 ships have the DNV Comfort Class notation. The positive feedback includes more satisfied passengers, considerably better working conditions for the crew, as well as a general improved Safety, Health and Environment situation on board.
Features
Vessels which fulfil the requirements applicable for this notation will be given the additional class notation COMF-C(crn). The requirements for on board climate are divided into three groups depending on the level of comfort achieved, i.e. comfort rating number (crn) 1, 2 and 3 where 1 represents the highest level of comfort, and 3 an acceptable level of comfort.
The requirements for the notation apply to the occupancy zone in designated locations, and apply to passenger vessels, to combined cargo/passenger vessels and cargo vessels.
The main parameters used as descriptors for indoor climate are related to the performance of the on board Heat, Ventilation, and Air Conditioning (HVAC) plant, and include: Ambient temperature, temperature gradient, air velocity, humidity and carbon dioxide concentration.
The following is evaluated with respect to indoor climate:- Basic design specification and system requirements
- System diagrams and heat/cooling balance calculations
- After delivery test program
- Test reports
- How to treat any excessive levels