Home » Post Irradiation Examination
Post Irradiation Examination

Purpose of

  • For performance evaluation and failure analysis of reactor operated fuel elements
  • To understand the material behaviour under irradiation and identify the component life limiting processes
  • To validate fuels performance codes
  • To collect data on various performance parameters such as , Swelling, Fission gas release and dimensional changes
  • To study the effect of design variables
  • To assist in the development of new fuels
  • For evaluation the performance of newly designed and developed reactor materials


Fuel PIE
Techniques used

  • Visual examination- using cell windows and scanning wall periscope
  • Dimensional measurement  and profilometry for continuous diameter variation measurement along the length
  •  Leak testing using various techniques as suited for the type of fuel/component
  • Gamma scanning  and gamma spectrometry
  • NDT evaluation by Ultrasonic testing, Eddy current testing  and Barkhaussen noise analysis
  • Estimation and analysis of released fission and retained fission gases
  • Mechanical and fracture property evaluation by mechanical testing by conventional and miniature specimen testing, Burst testing ,Impact testing and fracture mechanics testing
  • Remote metallography / ceramography  and image analysis
  • Hot hardness testing and automated ball indentation testing
  • Alpha and beta-gamma Autoradiography
  • Scanning Electron Microscope
  • Laserflash thermal diffusivity analysis
  • Thermo physical property evaluation by DTA, TGA, DSC and Dilatometry
  • X-ray residual stress measurement
  • High speed camera for recording transient experiments
  • Fuel safety experiment set up to simulate LOCA.
  • Thermal imaging system
  • Microwave based fuel dissolution and sintering systems
  • Hydrogen/deuterium charging and estimation systems IGF and Hot Vacuum Extraction Mass Spectrometry(HVE-MS)
  • Elemental analysis of solids by glow discharge optical emission spectrometry (GDOES), portable arc and spark optical emission spectrometry.
  • Mobile metallurgical laboratory for onsite use.


Post Irradiation Examination (PIE) is the study of nuclear fuel and structural components after irradiation in the reactor. PIE of fuel helps in identifying the cause of fuel failure and the behaviour of fuel under off-normal conditions. In addition, the information gained enables the users of fuel to assure themselves of its quality. PIE provides relevant feedback to the fuel designer, the fuel fabricator and the reactor operator to aim for zero fuel failures and improved fuel performance.

Laboratories with shielded containments are commonly referred to as hot cells. The word "hot" refers to the high radioactivity due to the nature of the materials examined. Hot cells are required to protect the individuals from radioactivity of the materials examined by providing a safe containment in which the equipment used for examination can be controlled and manipulated using Master Slave Manipulators (MSM). All the equipment used in the hot cells are specially designed to withstand high radiation and amenable to remote operation.

The division has also facilities for onsite PIE at reactor sites to maximize valuable irradiation performance data on reactor components and fuels stored in storage pools

Features of the Hot Cells

There are two hot cell facilities at PIED. Hot Cells-1 facility which has been serving for the last  thirty years and a new facility Hot Cells-2 . The details of these are as below


Hot Cells-1

Hot Cells-2

Number of cells



Type of radiation handled

Beta-gamma and low alpha up to 4% Pu

Beta-gamma and low alpha up to 4% Pu

Loading port dimension

150mm dia circular

500mm square

Maximum dimension of components that can be examined

100mm diameter and 4meter length

400mm diameter and  15meters length

Cell walls

1.2 m thick, high density concrete

1.5m thick high density concrete

Radiation Capacity

102 to 105 curies of 1.3MeV gamma radiation
(1 Curie = 3.7 x 1010 decays per second)

102 to 105 curies of 1.3MeV gamma radiation (1 Curie = 3.7 x 1010 decays per second)

Handling equipment

Remote operation using light duty master slave manipulators (MSM)

Remote operation using rugged duty master slave manipulators (RDMSM)

Viewing windows

Lead glass windows (oil filled)

Dry lead glass windows


Air, negative pressure of 1.5cm of Water gauge and 40 air changes per minute

Ventilation type

Once through with 40 air changes per minute and negative pressure of 1.5cm of Water gauge. Exhaust gases filtered through HEPA filter before safe disposal

Health physics coverage

Areas divided into 4 zones, (Red, Amber, Green and White) and all operations under complete HP coverage

Type of Fuels and components examined

PHWR, BWR, DHRUVA Experimental fuels  such as plate type fuels, TRISO coated particle fuel irradiated in research reactors, novel reactor fuels and components of small dimension

Large size fuel elements such as those of DHRUVA, AHWR and BWR. Large components such as pressure tubes, end fittings etc for PHWR and AHWR

Fuel materials

Al clad metallic U, Zircaloy-2 and Zicaloy-4 clad UO2, Zircaloy-2 clad (U- 4%Pu) O2, Zircaloy-2 clad  (Th-4% Pu) O2

Other activities

Failure analysis of various operating reactor

The Post Irradiation Examination facility at PIED, BARC

The Post Irradiation Examination facility at PIED, BARC


List of fuels examined at the PIE facility

Sl. No.

Fuel pins/bundles



Experimental UO2 Fuel pins (9 pins)



BWR (18 fuel pins)

TAPS, units 1 and 2


Experimental UO2-PuO2 fuel clusters (15 fuel pins)



PHWR UO2 (14 bundles)

Various power plants





Experimental ThO2-4%PuO2 (5 pins)



Experimental ThO2-6.75%PuO2 (2 pins)



Experimental UO2-3%PuO2 (2pins)



Experimental ThO2 (2pins)