Citizen science is transforming the ways scientific knowledge is created, in that citizens participate in active scientific research, and large scientific databases can be accessed online. However, data availability does not guarantee public use or the relevance of these resources. This paper addresses the ways in which non-expert adults involved in a citizen science initiative, perceive, understand and use its scientific information. Participants responded to an online questionnaire presenting air quality data from 'Sensing the Air' citizen science platform, followed by interpretation questions (n = 123). The results showed that 70% of participants were able to interpret the data presented in various visual representations. No differences were found between gender, age or education level. However, respondents with tertiary scientific education obtained higher average scores. Among users who had previous experience with the project, overall scores were higher, and differences based on respondents scientific education were fewer. This may suggest that while scientific education is important in providing skills for data interpretation, it is not the only way to acquire these skills. This study highlights the ability of non-experts to understand and apply scientific data in daily situations and the potential of citizen science to develop scientific skills, competencies and public understanding of science.