Time zone

A time zone was an area of specific time, utilised primarily as a means of keeping time via clocks. It was also used as a term when discussing time travel to specific destinations.

Time travel
In the war zones created by the War Lords, the Second Doctor and his companions moved from a time zone to another one passing through a mist. The intervention of the Time Lords sent the human prisoners back to their original time zones. (TV: The War Games)

The Malus, while creating psychic-projections from the past, was able to directly connect two time zones, allowing Will Chandler to come from the 16th century to the 20th century. (TV: The Awakening)

The Doctor's TARDIS brought the Fifth Doctor "in the right place, but the wrong time zone" when he bumped into an older Brigadier. When on Mawdryn's spaceship, the Doctors said they had a problem about the two different time zones of the two versions of the Brigadier on the ship. (TV: Mawdryn Undead)

Upon being activated by Davros, the Hand of Omega travelled to Skaro's time zone (TV: Remembrance of the Daleks) and detonated Skaro's second sun, (PROSE: The Stranger) causing the sun to go nova. (TV: Remembrance of the Daleks)

The stones of Stonehenge broadcasted the message about the Pandorica to every time zone. (TV: The Pandorica Opens)

Apalapucia had a two streams facility which enabled visitors dying of Chen-7, the one day plague, to live out their entire lives in the Red Waterfalls time stream, while their loved ones could watch them live in the Green Anchor time stream as it was, as the Eleventh Doctor stated, kinder than watching them die in their bed. It functioned, by using temporal engine, so that several time streams overlapped enabling thousands to be in the facility at one time. Amy Pond became trapped in the Red Waterfall stream when visiting with the Doctor and Rory Williams. The latter two used the TARDIS to break into her time zone though we're 38 years late. The time zone eventually collapsed when the aged Amy helped Rory and the Doctor retrieve her younger self, being erased as her timeline ceased to be. (TV: The Girl Who Waited)

River Song hinted the technology in the warehouse where a mysterious phone call to president Nixon started from could have originated in a different time zone. (TV: The Impossible Astronaut)

When repeatedly teleported in his confession dial, the Twelfth Doctor's ability to feel time travel made him state he should have been in the same time zone he had left, but the pattern of the stars in the sky suggested he had time travelled. (TV: Heaven Sent)

The Doctor,, Bill and Nardole once visited a colony ship that orbited a black hole. The time dilation it created caused there to be a gradual displacement in the time zones along the ship; the further a floor from the black hole, the faster time passed. As such, by the time 1000 years passed on Floor 1056, only a little over 2 days passed on Floor 0000, (TV: World Enough and Time) and two weeks on Floor 0507 was long enough for the Cybermen on Floor 1056 to evolve into their strongest model. (TV: The Doctor Falls)

Standard time on Earth
In a test run of the ATMOS system preceding the Sontaran invasion of Earth in 2009, 52 humans driving ATMOS-fitted cars were killed at the exact same time in 11 different time zones across the planet, including 5 A.M. in the United Kingdom, 6 A.M. in France, 8 A.M. in Moscow and 1 P.M. in China. (TV: The Sontaran Stratagem)

While speaking with the Eleventh Doctor on the phone, thinking he was a computer technician, Clara Oswald asked if she was phoning a different time zone and if it would have showed up in her bill, since their hours didn't match. (TV: The Bells of Saint John)