Volunteers at next summer's Olympics, likely to be laboring in blazing heat, will work no more than one hour at a stretch, and a manual will be drafted to help on-site leaders determine break times, according to officials.

The decision is one component of the Tokyo Metropolitan Government's overall basic policy, announced Monday, for dealing with the hot weather expected during the 2020 Games.

The officials said the basic policy on heat countermeasures and spectator guidance was based on the results of simulations conducted this summer at various test events.