The Colorado 3 Day Notice to Quit for Substantial Violation is a formal document used by landlords to notify tenants of a violation of the rental agreement or lease. The notice gives the tenant three days to either fix the violation or to move out of the rental unit. If the tenant does not fix the violation or move out within the three-day period, the landlord may file an eviction lawsuit. There are two types of Colorado 3 Day Notice to Quit for Substantial Violation: the Non-Emergency Violation Notice and the Emergency Violation Notice. The Non-Emergency Violation Notice is used for violations that do not pose an immediate threat to the safety, health, or welfare of the tenant, other occupants of the property, or the property itself. Examples of non-emergency violations include late rent payments, unauthorized occupancy, unauthorized pets, or unauthorized alterations. The Emergency Violation Notice is used for violations that pose an immediate threat to the safety, health, or welfare of the tenant, other occupants of the property, or the property itself. Examples of emergency violations include excessive noise, criminal activity, or destruction of property.