Ensuring good indoor air quality (IAQ) on passenger ships has become an increasingly important challenge, especially after the COVID-19 pandemic which showed the weaknesses of onboard HVAC systems in managing airborne pathogen spread. This thesis examines the role of air purification measures in enhancing indoor air quality (IAQ) on cruise ships, focusing specifically on the integration of emerging technologies within HVAC networks. The research is conducted in collaboration with Halton Oy, a worldwide supplier of marine HVAC systems, and AirForte Oy, a Finnish manufacturer of advanced solutions for air cleaning. A comprehensive state of the art review is conducted to to evaluate conventional purification technologies, such as mechanical filtration systems (HEPA, ULPA, EPA), UVGI disinfection systems, photocatalytic oxidation, and ionization systems.