Background: Indoor air quality (IAQ) represents a key public health and accessibility concern. Improving IAQ through policies and practices that reduce exposure to fragranced products and other indoor air contaminants may enhance accessibility and support equitable participation for individuals with MCS. Despite the widespread adoption of fragrance-free policies across sectors, evidence regarding their effectiveness remains limited. Methods: Using a mixed-methods design, we examined IAQ accessibility barriers and the effectiveness of fragrance-free policies in practice among sixty individuals with MCS across ten focus groups. Qualitative and quantitative data were collected in parallel, with thematic analysis conducted in NVivo. A structured IAQ and policy survey was administered to quantify reported experiences and policy impacts. Results: Approximately 63% of participants reported dissatisfaction with the indoor environments they encountered. Qualitative findings highlighted indoor environments as inaccessible, inadequately controlled, and associated with ongoing exposure to fragranced products as well as other indoor pollutants. These findings indicate that current approaches often fail to ensure accessibility, leaving individuals with MCS exposed and excluded from full participation in workplaces, healthcare settings, and other public spaces. Conclusion: Comprehensive fragrance-free policies incorporating source control, education, ventilation, and accountability mechanisms may reduce exposure while improving accessibility and inclusion across the built environment.