MODULE “PROJECT MANAGEMENTAND CONTROL”

RADIATION PROTECTION

SAFE DECOMMISSIONING OF NUCLEAR POWER PLANTS

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci”

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 2

CONTENTS

1. Radiation protection program

2. Radiation protection measures during decommissioning

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 3

TRAINING OBJECTIVES

Upon completion of training trainees should be able to: Describe the programme for radiation protection during

decommissioning. Describe the protective measures (technical and

organizational) during the implementation of the activities. Classify the types and periodicity of radiation control. List the measures for radiation protection improvement.

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 4

RADIATION PROTECTION

Use of protective equipment for shielding Availability of sufficient qualified staff occupied with radiation

protection Train decommissioning staff on needed skills, qualification and

radiation protection methods Organizational housekeeping experience Division of reactor building into zones (areas) Provision of appropriate system allowing to maintain workers and

public doses as low as reasonably achievable Document all radiation protection measures and results of surveys

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 5

CONTENTS OF CONCEPT AND RADIATION PROTECTION PROGRAMS

Measures to prevent exceeding of exposure doses Division of facility into zones (areas) Expected exposure evaluation Radiation control and facility site and environment investigation Monitoring and documenting of measurement results List of protective means and equipment to decrease ionizing radiation

impact List of technical means to measure radiation parameters Methods and means to decontaminate equipment and constructions Measures for RAW control and management Specific requirement for quality assurance Staff training

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 6

KNPP RADIATION PROTECTION POLICY

Basic Norms for Radiation Protection and BSS-115 of IAEA

The ALARA principle Obligations of the workers Control in zones (areas) of ionizing radiation Appropriate organizational structure

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 7

RADIATION PROTECTION OBJECTIVES

To maintain minimum but reasonably achieved level of individual and collective dose staff and population

To perform needed control of radioactive source To minimize radioactively contaminated surfaces,

equipment and staff To minimize radioactive waste generation

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 8

RADIATION PROTECTION ORGANIZATION

Radiation protection policy Structures for:

• Staff dosimetric control;• Operative assurance of radiation protection;• Environment monitoring.

Radiation protection instructions Procedures and programs for radiation protection activities Records and archive of activities for radiation protection

assurance

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 9

SPECIAL-PURPOSE INDICATORS FOR RADIATION PROTECTION ASSESSMENT

Annual collective dose (Man.mSv), outage or main activities

The highest annual individual dose Number of individuals who exceeded the administrative

limit Number of violations of radiation protection rules

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 10

ORGANIZATIONAL AND TECHNICAL MEASURES TO ENSURE RADIATION PROTECTION

Sanitary places including hot shower Sanitary locks Control and marking of radioactive contaminated zones

(areas), rooms Fencing RAW control Supplementary special protective clothing Decontamination of special clothing and shoes Decontamination of floors and walls Sanitary and hygienic rules

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 11

EXTERNAL RADIATION INDIVIDUAL DOSE MINIMIZATION

Control of current radiological conditions at the work place Planning of different activities Training and practice of workers with the help of models Use of procedures Remote control equipment is used Stay in rooms of higher level ionizing radiation is within

permissible limits Control of occupational doses

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 12

MINIMIZATION OF RADIONUCLIDE INHALATION

Experience of workers, good understanding of the conditions, organization and qualified management of the works

Use of protective clothing covering the whole body; protection of respiratory organs

Continuous operation of ventilation system during implementation of works

Dust equipment in operation (if needed), with aerosol filters Control of current concentration of radioactive aerosols in the air and

measurement of summary beta and gamma activity

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 13

LIMITATION OF CONTAMINATION SPREADING

Sanitary places prior to go into restricted area Fencing and tagging of work place and controlled area Storage and handling of RAW upon packing and/or

dumping in containers

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 14

INDIVIDUAL PROTECTIVE MEANS

Standard special clothing:• Cotton underwear and socks;• Cotton overall and a cap;• Shoes.

Additional special clothing:• Gloves – made of latex or fabric;• Rubber impregnated overall for work

with chemicals and liquid RAW ofhigh activity;

• Rubber overshoes - galoshes;• Filter mask.

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 15

TYPES AND PERIODICITY OF RADIATION CONTROL IN NPP

Continuous (permanent) RC:• Working media;• Technological process;• Individual dosimetry;• Radiation control of releases;• Environment radiation control;• Additional measurements.

24 – hour cycle of radiological control:• Working media;• Technological process;• Radiation control of releases.

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 16

TYPES AND PERIODICITY OF RADIATION CONTROL IN NPP – CONTND.

Monthly cycle of radiation control:• Individual dosimetry;• Technological process.

Periodic radiation control:• Individual dosimetry;• Environment radiation control;• Technological process.

Radiation control during outage:• Environment radiation control.

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 17

MONITORING AND CONTROL TO ENHANCE RADIATION PROTECTION

Documenting and research of radiological incidents Critical reviews to identify root causes of an issue Identification of radiation protection weak points Correction of identified issues by interference from

management

Project BG/04/B/F/PP-166005, Programme “Leonardo da Vinci” 18

REFERENCES

Decommissioning of Nuclear Power Plants and Research Reactors, Safety Guide, SS № WS-G-2.1 (1999)

International Basic Safety Standards for Protection against Ionizing Radiation and for the Safety of Radiation Sources, SS № 115 (1996)

Radiological Characterization of Shutdown Nuclear Reactors for Decommissioning Purposes, TRS № 389 (1998)

Regulation for the Safety of the Decommissioning of Nuclear Facilities, 2004

Regulation for the Basic Norms for Radiation Protection, 2004

Safety rules. Radiation protection in Kozloduy NPP plc.