Fire chiefs are urging Tour spectators to take care with their barbecues, cigarettes and rubbish.
The South Yorkshire brigade said recent dry weather could mean a greater chance of fires starting.
People are advised to site barbecues well away from buildings, shrubs and trees and never inside tents. They should take litter with them. The fire service has also written to residents near the route to say road closures may delay its response service.
Kevin Ronan, head of community safety, said: “We’re asking residents to take basic precautions, like testing smoke alarms and keeping an eye on cooking. If you do need us in an emergency, we will still respond. In the event of fire get out, stay out and call 999.”