Study to investigate the risk of fire in one room might cause smoke to spread through the ventilation system and into other rooms.
Calculation of Heating, Cooling and Airflow requirements, production of Airflow Diagrams, Cooling Medium Diagrams, Control Diagrams, D&IDs, P&IDs, Basic Philosophies, Equipment Lists, Data Sheets, GA-drawings, and other Basic Design documents. Selection of equipment is part of this stage.
Single Line Diagrams, Control Philosophies, Pressure Drop Calculations, Noise Calculations, Load Lists, Signal Lists, Instrument Lists, Equipment Foundation Drawings, and other Detail Design documents. Detail duct routing and design as well as verification and adjustment of equipment selection follows the detail design development.
Knowing the heat gains and losses, the specified internal conditions, fresh air requirements, minimum air changes and other special requirements enable the calculation of the required supply air.
The outdoor air intake ducts shall be designed to prevent any smoke or gas from reaching ventilated areas where it can cause hazard to people/equipment or ignition sources. The calculations will take into consideration F&G response time to close the relevant fire/gas damper.
The difference of supply air and extract air is loss of energy. If required we calculate the leakage rate of the ducting and building to find expected leakage, hence the required spare to be added on the supply air.
In special situations the calculation heat loss from ducts during WINTER and heat gains from ducts during SUMMER might be required to determine the necessary duct thermal insulation thickness or to design the right supply temperature. Thermal insulation of the supply ducts contributes to an effective HVAC System, by reducing the energy needed to maintain the correct SUPPLY AIR temperature to the rooms, as well as minimizing the risk of condensation.
The UPS (Uninterruptible Power Supply) rooms are typically rooms containing batteries designed to provide emergency backup electricity instantly if the main utility power fails. For this reason, calculations are sometimes done to verify how long it takes after loss of the main electricity before the rooms reach a critical temperature.
The HVAC system is an important part of the overall Fire & Gas system of an installation. It contributes to a safe and continuous operation of the installation. The basic rules are based on either national or international regulations in addition to IMO or company philosophies. Fulfilling applicable rules and regulations include correct application of fire dampers, duct classes, as well as complying to design and operational philosophies.
The target is always to keep as many rooms as possible operable but at the same time ensure safety for people and equipment. However, in some unwanted situations as a fire, smoke development or malfunction of safety equipment it might be required to shut down certain areas of the installation. This is often described in the Fire- and Safety Philosophy and might require specific actions to be taken for part of the installed equipment. It might include closing fire dampers, stopping AHUs/fans or other equipment, and sometimes starting smoke extract fans. This will typically be reflected in a Cause & Effect diagram.
