Fukushima 1 Nuclear Accident Day 5: Tuesday 15 March

06:00 (approximate)

A fire in unit 4 reportedly breaks out around 6AM

A third explosion occurred at Fukushima I, unit 2 and damage of the containment building was feared. Reactor unit 2's pressure-suppression system was feared damaged, and the radiation level exceeded the legal limit to reach 965.5 µSv/hour. The radiation level later fluctuated up to 8217 µSv/hour, two hours after the explosion. The level went down to 2400 µSv/hour shortly later. Workers at the plant started evacuation, with a select few remaining to keep the reactors cooled. The plant's operator said the nuclear fuel rods could be melting. Additionally, it was confirmed that the 4th floor rooftop area of the Unit 4 Nuclear Reactor Building had sustained damage, likely caused by the earlier blast of Unit 3.

07:00

08:30

Radiation reading at the Fukushima I Nuclear Power Station (NPS) border is 8217 µSv/hour.

A fourth explosion and resulting fire is reported at unit 4. IAEA Reports that initial fire at unit 4 started at 2354 UTC on March 14th.

09:14 (approximate)

MSNBC reported that radiation measurements spiked at 11,900 µSv/hour around 0914 as measured at the front gate of the facility and speculated it was caused by the third explosion at unit 2.

09:40

The Fukushima I Unit 4 building caught fire around 6AM, likely releasing radioactive contamination from the spent fuel stored there. TEPCO said workers extinguished the fire by 12:00. As radiation levels rose, some of the fifty employees still at the plant were evacuated.

10:22

The Fukushima I radiation monitor readings outside of the buildings were 30 mSv/hour between Unit 2 and Unit 3, 400 mSv/hour beside Unit 3, and 100 mSv/hour beside Unit 4.

11:00 (approximate)

IAEA Reports that initial fire at unit 4 was extinguished at 200 UTC on March 15th.

11:35

At Fukushima II (Dai-Ni), Units 1, 2, and 3 are in cold shutdown. For Unit 4, work is in progress to restore cooling and bring it to cold shutdown.

13:35

No fly zone declared for 30 km around the Fukushima I plant. Prime Minister warns of radiation hazard and further radiation leaks.

16:09

There is a fire at a spent fuel pond of a reactor and radioactivity has been released into the atmosphere, says the IAEA according to AFP news agency.

16:30

Radiation reading at the Fukushima I Nuclear Power Station (NPS) border is 489.8 µSv/hour.

16:38

The AFP reports that the fire previously reported at unit 4's spent fuel pond had released "radioactivity... directly into the atmosphere" according to the IAEA .

17:00

The fire at the spent fuel pond has been put out by Japanese authorities according to the IAEA they state "Japanese authorities have confirmed that the fire at the spent fuel storage pond at the Unit 4 reactor of Fukushima I nuclear power plant was extinguished on 15 March at 17:00 JST."

17:03

There has been a slight rise in temperature of two more reactors at Fukushima I nuclear plant, the chief government spokesman says according to AFP.

18:00

Japanese nuclear safety official has confirmed reports that the water inside the waste fuel storage pool for the Unit 4 Fukushima reactor may be boiling, AP reports.

19:00

21:00

The water level in Fukushima I Unit 5 has been decreasing. Workers plan to use Unit 6's diesel generator to help pump water into Unit 5. Japanese authorities have also informed the IAEA that at 12:00 UTC of 15 March the water level in Unit 5 had decreased to 201 cm above the top of the fuel. This was a 40 cm decrease since 07:00 UTC of 15 March. Officials at the plant were planning to use an operational diesel generator in Unit 6 to supply water to Unit 5.

23:35

Radiation reading at the Fukushima I Nuclear Power Station (NPS) border is 6308 µSv/hour.