A Radiation Protection Expert is a professional who operates in the field covered by legislative material for Health and Safety at work. The person on behalf of the employer has the responsibility of supervision and monitoring the physical risk to the workers and the population to ionising radiation. The RPE has to update training and necessary knowledge recognised by the responsible Authority in accordance with D.Lgs. 101/20.
Firstly before buying any X-Ray device or radioactive source it is imperative to contact a Radiation Protection Expert whose competence is recognised by the relevant authorities.
The radiation dose absorbed by a person is the amount of energy deposited in the human tissue by radiation and it is measured by the SI unit Gray (Gy)
The Gray (Gy) is a derived unit of ionising radiation dose in the International System of Units (SI). It is defined as the absorption of one joule of radiation energy per kilogram of matter.
1Gy=1J/1K
The biological risk of exposure to radiation is measured using the conventional unit Sievert (Sv)
1 Sv=1 Gy (for electron and photon).
The general guidelines for controlling exposure to ionising radiation are:
It is obligatory for a worker to inform the employer as soon as possible about a pregnancy.
Pregnant females and breast-feeding employees are forbidden to work or be present in an area that has a radiation level of greater than 1 mSv because of the risk of contamination.
Some of the controls performed by a Radiation Protection Expert (RPE) at a radioactive source are as foreseen in the Legislation:
As well as the above mentioned controls the RPE has to comply with the Legislation Laws 101/20.
Some of the controls performed by a Radiation Protection Expert (RPE) at a radioactive source are as foreseen in the Legislation:
As well as the above mentioned controls the RPE has to comply with the Legislation Laws 101/20.
Radon is a radioactive colourless, odourless and tasteless gas being neither combustible or explosive. It is classed as a health hazard and is second only to smoking in causing lung cancer.
Radon is a noble gas which is formed during the disintegration of Radium, which in turn is produced from the decay of Uranium. Since Uranium is present, with varying degrees of concentration everywhere in the earth’s crust, Radon is also present almost everywhere in the ground.
Radon is radioactive, meaning its atoms disintegrate (decays with a half life of about 4 days) giving further radioactive elements and compounds such as Polonium, Lead and Bismuth. These are solid particles and adhere to dust present in the air.
Radon atoms do not bind to other atoms, but are released from the ground and pass into the air we breathe.
Being a gas Radon is inhaled and exhaled, however it’s derivatives (the real risk), form a type of radioactive aerosol which adhere to the bronchial walls exposing them to alpha radiation and thus damaging lung tissue.
Radon is emitted from rocks and soil, it then emerges on the surface of the earth transported by water or underground gases. In open air it is quickly diluted and therefore practically harmless, while in closed spaces it accumulates and presents a resident danger. The main pathway for the transport of Radon into buildings is through the so called “Chimney effect” in which hot air rises inside leading to an area of weak pressure on the lower floors facilitating the aspiration of Radon from the soil below.
A second source of Radon is from building materials. This source is usually secondary to the ground source. In addition, Radon can dissolve in water and enters houses as drinking water.
The propagation of Radon gas in soil and its penetration into buildings is based on extremely complex dynamics: adjacent buildings constructed identically may have totally different Radon concentrations. Only an on-site measurement can provides accurate levels of concentration. Radon in air is measured in Bq/m3 (1 Bq / m3 = 1 decay per second per cubic meter).
The maximum annual average concentration levels of Radon activity in the air for homes and workplaces are:
a) 300 Bq/m3 for homes and workplaces;
b) 200 Bq Bq/m3 for homes built from 2025;
Decommissioning means taking out of active use and dismantling structures, removing contaminated materials to appropriate facilities and returning the land to Green Field status.
The Radiation Protection Expert (RPE) has to evaluate the doses of radiation exposure for the workers and the general population at each stage of the dismantling. Also to calculate the radiological risks under normal conditions and in risk situations.
The RP service acts in accordance with the directives and under the responsibility of the Radiation Protection Expert.
It has the role of carrying out surface contamination measurements, contamination in air, contamination in water and measuring radiation at various distances from the contaminated parts of the system.