A record heatwave in July 2018 killed over a dozen people in Tokyo with monthly average temperatures transcending 30 degrees for the first time in 20 years.
With temperatures rising to 35 degrees Celsius and humidity of 75% on Thursday, Tokyo 2020 organisers had the perfect weather to try out their heat countermeasures and preparedness for next year's Olympics at the beach volleyball test event.
Although it has been less hot this year, a record heatwave in July, 2018, killed over a dozen people in Tokyo with monthly average temperatures transcending 30 degrees for the first time in 20 years.
Tokyo 2020 organisers will employ wet bulb globe temperature (WBGT) measuring devices at all venues as a step in their readiness for high temperatures.
The WBGT device factors in temperature, humidity, wind speed and solar radiation, producing a rating based on the variables and the Tokyo Metropolitan Government (TMG) advise citizens against exercising when the WBGT rating is over 31.
On Thursday, however, the WBGT rating at the beach volleyball venue in central Tokyo was as high as 31.7 but organisers said it did not mean that an Olympics event would be cancelled should this happen during the Games.
The WBGT reading will be one of many factors to be considered, in consultation with the sport's federation, while judging the safety of an event going ahead, the organisers said.
"It all depends on a situation, but for the spectators, we will prepare cooling facilities and goods for them," said Ken Wakabayashi, an environment official at TMG.
"At the same time, we would like to encourage them to get information on heat countermeasure and enjoy the event."
Among other countermeasures tested were water vapour sprays for supporters arriving at the venue, shaded or air-conditioned rest areas within the venue, and the distribution of water and ice packs to athletes and fans.
With two people this week needing medical treatment at the beach volleyball, including a person who suffered a heatstroke, organisers also wanted to test their readiness for people falling ill during the Games.
The TMG said their first aid response worked well.
"As far as our First Aid Station is concerned, I think we managed to make a correct judgment and provide an appropriate treatment," said Tomoko Suemura, who works within TMG's Games preparation department.
"We feel it is necessary to discuss how to deal with various medical cases in coming months."