Caesium-137 timeline

from the Caesium-137 stick event

Disappeared from the company producing coal-fired power plants in Prachinburi province.

By the way, involved jointly examined and searched for 10 days, discovered that it was forged from an iron smelting furnace in Prachinburi province.

Initially, officials from the Office of Atoms for Peace

and relevant agencies have jointly examined the level of radioactivity that has spread into the natural system

in a nearby radius is still safe

Caesium-137 timeline so far, has it been fused yet?

how dangerous

  • February 23, 2023, expected to disappear today

It is thought to be the day the cesium-137 rod disappeared.

  • March 10, 2023, the company filed a complaint

Officers from National Power Plant 5A in Industrial Estate 304, Tha Tum Subdistrict, Sri Maha Pho District, Prachin Buri Province reported to the police that the cesium-137

missing from the installation point

  • March 14, 2023, Prachinburi governor, press conference, cesium-137 missing

3:00 p.m. Prachin Buri Governor

Press conference at Prachinburi City Hall

To the event that the object containing radioactive cesium-137 disappeared from National Power Plant 5A in Industrial Estate 304, Tha Tum Subdistrict, Sri Maha Pho District, Prachin Buri Province.

Details of the first day's news indicate cesium-137 in a 5-inch diameter pipe, 12 inches long, installed in 1991 (read the original news here).

  • March 15, 2023, searched throughout the district, could not find

    set a clue reward of 50,000 baht

Search for cesium-137 rods

Prachinburi Provincial Officer

and officials from the Office of Atoms for Peace

and officials from the National Power Plant 5A jointly search for cesium-137 rods.

At 30 antique shops in Si Maha Phot District, notifying the founders of 50,000 baht (listen to the news clip here).

Details Additional cesium-137 rod inside, diameter 5 inches, length 8 inches, weight 25 kilograms, installed in 1995 (read original news here)

  • March 16, 2023, adding a search reward of 100,000 baht

Prachinburi Provincial Security Office

Atomic Personnel for Peace

Inspect National Power Plant 5A Company, expected to still be in the company

and monitor CCTV

Prachin Buri Province

Has announced a clue to bring back the lost radioactive material.

will receive a prize of 100,000 baht (read the original news here)

  • March 19, 2023 found "Casium-137 rods" ordered to close the factory.

Mr. Ron Ron Nakornchinda, Governor of Prachinburi Province, together with Mr. Permsuk Sajjapiwat, Secretary-General of the Office of Atoms for Peace

Going to the area to inspect the work of the staff

Preparing to announce the discovery of cesium-137 clues.

From two iron smelters, smelters, by checking down to the area from 8 furnaces using radioactivity measuring equipment

A substance is detected that is believed to be part of "

Casium-137 rods

" by ordering the smelter to be shut down for inspection.

(Read original news here)

  • March 20, 2023 Press conference found "Casium-137 rods"

10:00 a.m. Press conference has found "Casium-137" (listen to the news clip here).


I need to continue checking how it disappeared.

confirm that it does not affect human life

Not a Chernobyl or Fukushima nuclear accident.

Metal smelting plant on March 18-19, 2023. Various dust particles are collected in 24 bags, 1 tonne each.

24 tonnes of cesium-contaminated red dust, including one bag, was taken to fill the land behind the smelter.

and has been dug back and packed completely

(Read original news here)

  • March 21, 2023 Check cesium-137

    whether it was melted into dust or not

Office of Atoms for Peace Scientist

Cesium-137 was found in furnaces in filter systems and fume hoods.

Contamination with radioactive cesium-137 was found.

in metal furnaces, low level 0.07-0.10 microSv/1 hour in 1 furnace

- Check the dust extraction system and the dust filter system.

from smelting on March 18-19, 2023

- Check the soil around the factory.

By using a dose measuring device installed in a car, the radiation level was found to be 0.03-0.05 microSv/1 hour, which was equal to the natural radiation level.

(Read original news here)

- Check the soil around the factory for 3-5 kilometers, no contamination found.

(Read original news here)

- Provincial Public Health

Urine test for 70 factory employees sent to the laboratory of the Office of Atoms for Peace.

with a gamma ray meter

No radioactive contamination was found on clothing and body.

And the white blood cell results showed no abnormalities.

People in the area if they have any of the following symptoms

must contact a doctor

1. Nausea, vomiting.

2. Burns occur on the skin.

Watch out for signs of radiation sickness.

1. Early warning

These symptoms are manifested after a few hours of exposure to radiation, including nausea, vomiting, shortness of breath, exhaustion, loss of balance, red skin.

2. The latent phase

is a phase that is calm, does not show symptoms, and the duration cannot be determined.

depending on the amount of radiation received

3. The true birthmark phase

is a continuous phase from the latent phase, with fever, loss of appetite, weight loss, bleeding, hair loss, shock, memory loss, loss of consciousness.

and may die

What is cesium-137 used for?

Cesium-137 (Cs-137)

is used to measure the flow rate.

found in moisture measuring devices

The missing one works with a laser machine used to trap dust and ash in power generation, a steam power plant, installed in 1991. Things to follow

in the event of the news of "missing cesium-137"

1. Who smuggled bars?

"Casium-137" leaves the National Power Plant 5A factory.

2. Who buys the ingots?

“Casium-137” smuggled out

3. How many people were exposed to cesium-137 and how many people needed long-term follow-up?

Compare the effects of cesium-137 (2023) with the news of cobalt-60 (2000).


used in the power plant industry

It involves the process of detecting the flow rate of ash in a coal-fired power plant.

The volume of cesium bars in news

It is not yet dangerous to human life.

  • Value detected at smelter 0.07-0.10 µS/1 hour (low level).

  • The value detected at a radius of 3 km is 0.03-0.05 µS/1 hour (at the natural level).

Radioactive kisivert safe for human body

Information from the book stays safe with Atoms.

Information about nuclear energy

from the Office of Atoms for Peace

It was found that exposure to radioactive

Acute and long-term effects on the skin and body include:

1. Acute radiation exposure (Acute Exposure) is called radiation accident

2. Chronic radiation exposure (Chronic Exposure) is called low dose radiation exposure.

but will accumulate in the body

Until causing leukemia, various cancers and cataracts

safe radiation dose

general public

1. The body should not receive 1 mSv per year.

2. Eye lens, reproductive organs, bone marrow 15 mSv per year.

3. Skin, thyroid, hands, limbs 50 mSv per year.

Cobalt-60 is used for what


is a radioactive material used in the medical industry.

used with medical equipment

on objects containing cobalt-60

There will be a radioactive hazard symbol.

Therefore, the importation of medical devices containing radioactive materials must be notified to the government safety agency.

and systematically stored and destroyed

Looking back on the lessons of 23 years, “Cobalt-60”, Samut Prakan Province


is not radioactive that escaped from Thailand's first radiation protection system.

Since 1961, there was a law to protect the use of radioactive substances, there was an accident with radioactive leak of Cobalt-60 news in Samut Prakan Province.

Caused by disassembling a radiation machine, containing 15.7 TBq of cobalt-60, 4 men sold it to an antique shop in 2000, causing injuries, deaths, and a pregnant woman who requested termination. Pregnant due to concerns about potential long-term effects

Cobalt-60 Year 2000 Samut Prakan Province

Retrace the footsteps of 1,872 affected people.

Born in Samut Prakan Province in 2000

Four of them were men disassembling a irradiator containing 15.7 TBq of cobalt-60.

People within a radius of 100 meters

10 people, a family of an antiques shop and an employee, were exposed to radiation.

  • 4 people* received more than 4 Gy of radiation

  • 6 people received mild radiation,

    52 people were workers

    from the Bureau of Atomic Energy for Peace

    Exposure to safe levels of radiation (32 mSV)

* Within two months, 3 people died

**The bodies were not allowed to be cremated.

Because the villagers fear the spread of radioactive materials caused by incineration.

People within a radius of 50 meters

- 258 people, long-term follow-up

- 1 person requesting termination of pregnancy

Read related news:

  • Relive the Cobalt-60 disaster

    Saleng collected to sell at an antique shop.

  • Radioactive cesium-137 disappears mysteriously, do not repeat cobalt-60 radiation incident 

  • How does cesium-137 get contaminated in the body?

    How dangerous is it?