(CNN) Here's a look at the International Atomic Energy Agency and nuclear power.
The International Atomic Energy Agency (IAEA) inspects nuclear and related facilities under safeguard agreements. Most agreements are with countries that have committed to not possessing nuclear weapons. The IAEA is the verification authority to enforce the Treaty on the Non-Proliferation of Nuclear Weapons (NPT).
The IAEA has 178 member states (as of September 19, 2023).
Rafael Grossi has been the director general of the IAEA since December 3, 2019.
There are 35 member countries on the IAEA Board of Governors, which meets five times a year.
The IAEA has about 2,500 employees.
The IAEA sends out inspectors to monitor reactors.
The IAEA helps countries prepare and respond to emergencies.
There are about 417 nuclear power reactors in operation.
There are more than 50 nuclear power reactors under construction.
There are more than 90 operational nuclear reactors in the United States.
1939 - Nuclear fission is discovered.
1942 - The world's first nuclear chain reaction takes place in Chicago as part of the Manhattan Project, a US research program aimed at developing the first nuclear weapons.
July 16, 1945 - The United States conducts its first nuclear weapons test in New Mexico.
August 6, 1945 - An atomic bomb is dropped on Hiroshima, Japan.
August 9, 1945 - An atomic bomb is dropped on Nagasaki, Japan.
August 29, 1949 - The Soviet Union conducts its first nuclear weapons test.
December 1951 - Electricity is first generated from a nuclear reactor at the National Reactor Testing Station in Idaho.
October 3, 1952 - The United Kingdom conducts its first nuclear weapons test.
December 8, 1953 - In a speech to the United Nations General Assembly, US President Dwight D. Eisenhower asks the world's major powers to work together in developing peacetime uses of the atom. This is known as the Atoms for Peace program, and 40 countries participate. Also during this speech, Eisenhower proposes the creation of an international agency to monitor the spread of nuclear technology.
June 26, 1954 - In the Soviet Union, the first nuclear power plant is connected to an electricity grid to provide power to residences and businesses in a town near Moscow.
1957 - The IAEA is established to facilitate the peaceful use of nuclear energy.
1950's - Brazil and Argentina begin research and development of nuclear reactors.
February 13, 1960 - France conducts its first nuclear weapons test.
October 16, 1964 - China conducts its first nuclear weapons test.
March 5, 1970 - The NPT goes into effect.
May 18, 1974 - India conducts its first nuclear weapons test.
March 28, 1979 - A partial meltdown of the Three Mile Island nuclear power plant occurs in Middletown, Pennsylvania. It is determined that equipment malfunctions, design-related problems and human error led to the accident.
April 26, 1986 - Reactor number four explodes at the Chernobyl Nuclear Power Plant, releasing large amounts of radiation into the atmosphere.
September 24, 1996 - The United States, China, France, the United Kingdom, Russia and 66 other UN member countries sign the Comprehensive Nuclear Test Ban Treaty, barring the testing of nuclear weapons.
May 1998 - India and Pakistan test nuclear devices amid tensions between the neighboring countries.
January 10, 2003 - North Korea announces its withdrawal from the NPT.
August 2003 - IAEA inspectors find traces of highly enriched uranium at an electrical plant in Iran.
December 19, 2003 - Libya announces that it will dismantle its WMD program, in cooperation with the IAEA as well as the United States and the United Kingdom.
October 7, 2005 - The IAEA and Director General Mohamed ElBaradei are named the winners of the Nobel Peace Prize.
March 11, 2011 - A 9.0 magnitude earthquake strikes near the coast of Honshu, Japan, creating a massive tsunami. The tsunami knocks out the Fukushima Daiichi nuclear power plant's cooling systems. The cores of three of six reactors are damaged by overheating. Resulting hydrogen explosions blow apart the buildings surrounding two reactors.
May 30, 2011 - Germany announces it will abandon the use of all nuclear power by the year 2022. This repeals a 2010 plan to extend the life of the country's nuclear reactors.
November 11, 2013 - Iran signs an agreement with the IAEA, granting inspectors access to nuclear sites.
July 14, 2015 - After 20 months of negotiations, Iran reaches a comprehensive agreement (The Joint Comprehensive Plan of Action (JCPOA)), with the United States and other countries that is aimed at reining in Iran's nuclear program. In exchange for limits on its nuclear activities, Iran will get relief from sanctions while being allowed to continue its atomic program for peaceful purposes.
August 11, 2015 - Japan restarts a nuclear reactor on the island of Kyushu. It's the country's first reactor to come back online since the 2011 tsunami.
January 16, 2016 - The IAEA confirms that Iran has taken all of the steps outlined in the nuclear deal, allowing for sanctions to be lifted, as per the agreement.
May 8, 2018 - US President Donald Trump announces that the United States will withdraw from JCPOA and will be imposing "the highest level of economic sanction" against Iran. In Tehran, Hassan Rouhani says Iran will take a few weeks to decide how to respond to the US withdrawal but says he had ordered the country's "atomic industry organization" to be prepared to "start our industrial enrichment without limitations."
May 8, 2019 - Rouhani announces a partial withdrawal from the JCPOA.
February 16, 2021 - The IAEA reports it received a February 15 letter from Iran stating that it will stop implementing provisions of the additional monitoring protocol as of February 23. This will effectively limit which facilities nuclear inspectors can scrutinize and when they can access them, making it harder for experts to determine if Tehran is attempting to develop nuclear weapons.
February 18, 2021 - The Joe Biden administration releases a statement indicating that the United States is willing to sit down for talks with Tehran and other signatories to the Iran nuclear deal, before either side has taken tangible action to salvage or return to compliance with the agreement.
February 21, 2021 - In a joint statement, the IAEA and Iran announce they have reached a deal in which Iran will give IAEA inspectors continued access to verify and monitor nuclear activity in the country for the next three months.
March 15, 2023 - A spokesman from the IAEA tells CNN in an email that "approximately 2.5 tons of natural uranium" contained in 10 drums were found to be missing from supplies held in Libya during an inspection on March 14, 2023.
July 7, 2023 - IAEA Director General Grossi tells CNN that Japan's plan to start releasing treated radioactive water into the ocean in August is safe and there is no better option to deal with the massive buildup of wastewater collected since the 2011 Fukushima nuclear disaster, but public anxiety remains high.