“The primary mechanism for the prevention of carbon monoxide exposure to aircraft occupants is to carry out regular inspections of piston-engine exhaust systems to identify and repair holes and cracks, and to detect breaches in the firewall between the engine compartment and the cabin.”
https://www.atsb.gov.au/publications/safety-advisory-notice/ao-2017-118-san-001/
Carbon monoxide detectors provide warning to aircraft occupants of the presence of CO levels in the cabin that are above safe concentrations.
https://www.atsb.gov.au/publications/safety-advisory-notice/ao-2017-118-san-002/?fbclid=IwAR1IHjUuevFDmY24m-ZyceYP_PW3_ycyArV_zfyuP67s3L4i6fP8pmATLHI#.Xv8_2EcB0Lo.facebook
Sydney, Australia – “The ATSB considers the levels of carbon monoxide were likely to have adversely affected the pilot’s ability to control the aircraft…”
https://www.news.com.au/travel/travel-updates/health-safety/sydney-seaplanes-crash-carbon-monoxide-poisoning-blamed-for-2017-fatalities/news-story/f5f0f6ab476a887b6c9ecc93eab2e4f2?fbclid=IwAR0if_G_afaKD8tjs0cRXQrGaIWQTJ6A0vqoE_MltDMGzhenB8-halKh_NA#.h8lqc
“As cold winter temperatures arrive, you’ll probably use your airplane’s heater extensively. Here’s how cracks in your muffler could cause in-flight carbon monoxide poisoning, and what you can do to avoid it…”
https://www.boldmethod.com/learn-to-fly/systems/carbon-monoxide-poisoning-in-cold-winter-air-this-year/?fbclid=IwAR2dtBpBMFTiaOg8Pu5Yo7zjR501_PjHNUXbiRJvRl4G5ZXQAYEytzx86Eo