This study looks at how air quality in the Intensive Care Unit (ICU) affects patients. *Air pollution* consists of tiny particles in the air, like PM2.5 and PM10, which can enter our lungs and bloodstream through alveoli (tiny air sacs in our lungs). These particles might cause inflammation, leading to heart problems like arrhythmia (irregular heartbeat) and myocardial infarction (heart attack). The study will help us understand if air pollution in the ICU affects patients, especially those with heart issues or elderly patients. *Hospital Acquired Infections (HAIs)* are infections patients get while receiving treatment in hospitals, costing a lot of money and affecting many people. Monitoring *Indoor Air Quality (IAQ)*, which includes temperature, humidity, CO2 level (carbon dioxide), and particulate matter, can help keep patients and staff healthy.

• This study requires a stay in the ICU for at least 2 days.
• Participants must be over 18 years old and give consent.
• Pregnant women cannot participate.