This gas causes fatigue in lower concentration, and at higher concentrations, headaches, dizziness, confusion, nausea, and impaired vision and communication.
Death is a possibility at very high concentrations.
Unvented kerosene and gas heaters can also release nitrogen oxides, a major component of the smog we see over congested areas. What You Can Do About Combustion Sources Replace devices that have pilot lights with ones that use electronic ignition. Upgrade woodstoves to hi-efficiency sealed types. Vent any unvented kerosene or gas heaters being used indoors. This should also be done for safety reasons.