FAQ

What is a Radiation Protection Expert (RPE)?

A Radiation Protection Expert (in Italy is known as a Qualified Expert (QE) in Radioprotection) 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 QE has to update training and necessary knowledge recognised by the responsible Authority in accordance with D.Lgs. 230/95.

Purchase of X-Ray equipment or a radioactive source. What is needed?

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.

What is a radioactive dose and how is it measured?

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).

How do you protect yourself from ionising radiation?

The general guidelines for controlling exposure to ionising radiation are:

  • Minimising exposure time
  • Maximising the distance from the radiation source
  • And shielding yourself from radiation source

Can pregnant women continue to work in an ionising radiation environment?

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.

What are the controls for the radiation from X-Ray instrumentation?

Some of the controls performed by a Radiation Protection Expert (RPE) at a radioactive source are as foreseen in the Legislation:

  • For sealed sources the verification of the casing surrounding the source
  • The control of the surrounding environment for contamination and the instruments used with the radioactive source
  • To check the correct labelling of the radioactive sources and classified zones
  • To measure the levels of radiation at the source and at predefined distances from the source (if Gamma or X radiation)
  • Verification of the correct radioactive waste management
  • The availability of the Internal Rules for the radioprotection in the area of the radioactive source

As well as the above mentioned controls the RPE has to comply with the Legislation Laws 230/95.

What are the controls for a Radioactive source?

Some of the controls performed by a Radiation Protection Expert (RPE) at a radioactive source are as foreseen in the Legislation:

  • For sealed sources the verification of the casing surrounding the source
  • The control of the surrounding environment for contamination and the instruments used with the radioactive source
  • To check the correct labelling of the radioactive sources and classified zones
  • To measure the levels of radiation at the source and at predefined distances from the source (if Gamma or X radiation)
  • Verification of the correct radioactive waste management
  • The availability of the Internal Rules for the radioprotection in the area of the radioactive source

As well as the above mentioned controls the RPE has to comply with the Legislation Laws 230/95.

What are the quality controls for an X-Ray machine?

The purpose of Quality Control (QC) together with the periodic testing is to verify the correct functionality of the radiology equipment. This ensures that the patients are only exposed to the lowest possible radiation levels, compatible with obtaining the diagnostic information requested.
The Quality Control is part of the overall Quality Assurance program foreseen for Italian radiodiagnostic centres and in compliance with Legistation D.Lgs. 187/2000, that includes:

  • Proof of registration and installation control testing: to control that the radiological instrument conforms with characteristics set out in terms of purchase and should be followed in the case of new installations or important modifications
  • Verification of performance and condition of the instrument: verify the correct functioning of the instrument on the basis of the task it is expected to do
  • Periodic Maintenance checks: verify the correct functioning of the instrument in a periodic time scale
  • The Quality Assurance program for radiological devices also foresees
  • Verification of Minimal Critical Acceptability tolerance limits for the reference parameters of the instrument described in D.Lgs. 187/2000
  • To draft a Quality Assurance Manual: this document establishes the criteria, the form and the time line in which the Quality Control test should be performed, elaborated with reference to protocols used by national and International Scientific organisations and institutions
  • Training personnel in the field of radioprotection of the patient
  • Evaluation and control of Personal Protection Equipment (PPE) and Collective Protection Equipment (CPE) for the radioprotection of the patient

The outcome of the Quality Control procedure will be submitted to the Medic responsible for the radiological system and he/she will evaluate the suitability for clinical use.

Radon . What is it? Where does it come from, what are its effects and how does it entre a building? What is the reference legislation regarding Radon?

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 D.Lgs.230/95 and subsequent amendments foresees the need for Radon control in the following workplaces:

  1. Tunnels, subways, catacombs, caves, underground rooms
  2. Other workplaces located in areas associated with Radon risk
  3. Spa establishments

The law has set a first threshold of 400 Bq/m3 and a second of 500 Bq/m3. Exceeding the first threshold implies the repetition of the measurements the following year. Exceeding the second threshold obliges the employer to notify the supervisory bodies and put in place a remedial action plan within three years using a Qualified Expert in radiation protection and verification of improvement through new measures.
The European Directive 2013/59/Euratom, which must be implemented by Member States by February 2018 has fixed a lower reference level of 300 Bq/m3 for the workplace and for housing.

What is decommissioning of a Nuclear facility? What is the role of the Qualified Expert (Radiation Protection Expert) and the radioprotection service ?

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. (More Info)