KTM 690 SMC Owner's Manual page 146

MAINTENANCE WORK ON CHASSIS AND ENGINE
Danger
Danger of poisoning Exhaust gases are poisonous and can result in
unconsciousness and/or death.
–
When running the engine, always make sure there is sufficient ventilation,
and do not start or run the engine in a closed space without an effective
exhaust extraction system.
–
Start the engine and check that it is oil-tight.
–
Check the engine oil level. ( p. 136)
144