I’m concerned about indoor air quality in my van. There are things that can kill you quickly like carbon monoxide and things that will make you sick and lead to long term health issues like formaldehyde. Those of us on the west coast have also seen summer air quality worsen due to forest fires and the resulting quantity of PM2.5 particles in the air. I have two splurges to mitigate: a small HEPA filter that runs on a 12v and an indoor air quality monitor. This is the one I picked: https://www.amazon.com/dp/B085C45TX9/ref=cm_sw_em_r_mt_dp_0BGE0WP7TXT1YYQF3G5Q