RADIOGRAPHY, X -Rays, Properties of X-ray, Applications of X-ray, GAMMA – RAY, RADIATION SAFETY

RADIOGRAPHY

Radiography is a medical imaging technique that uses X-rays or gamma rays to create images of the internal structures of the body. X-rays and gamma rays are both forms of electromagnetic radiation, but they differ in their sources and energies.

The electromagnetic spectrum refers to the entire range of electromagnetic radiation, which encompasses all types of electromagnetic waves, including visible light, radio waves, microwaves, infrared radiation, ultraviolet radiation, X-rays, and gamma rays. Electromagnetic radiation is a form of energy that travels through space in the form of oscillating electric and magnetic fields.

The electromagnetic spectrum is typically divided into different regions or bands based on the wavelength or frequency of the waves. Each region of the spectrum has unique properties and interactions with matter. Here are the major regions of the electromagnetic spectrum in order of increasing frequency and decreasing wavelength:

1.     Radio Waves: These have the longest wavelengths and lowest frequencies in the spectrum. They are used for various purposes such as communication, broadcasting, and radar.

2.     Microwaves: These have shorter wavelengths and higher frequencies than radio waves. They are used in microwave ovens, satellite communications, and wireless networks.

3.     Infrared Radiation: Infrared waves have longer wavelengths and lower frequencies than visible light. They are commonly used in heat lamps, remote controls, and thermal imaging.

4.     Visible Light: This is the portion of the spectrum that can be detected by the human eye. It consists of different colors ranging from red (longest wavelength) to violet (shortest wavelength).

5.     Ultraviolet Radiation: Ultraviolet (UV) waves have shorter wavelengths and higher frequencies than visible light. They are responsible for sunburns and can be used in sterilization and fluorescence.

6.     X-rays: X-rays have shorter wavelengths and higher frequencies than UV rays. They are commonly used in medical imaging, such as X-ray radiography and CT scans.

7.  Gamma Rays: Gamma rays have the shortest wavelengths and highest frequencies in the electromagnetic spectrum. They are produced by radioactive decay and nuclear reactions. Gamma rays are used in radiation therapy and sterilization processes.

X -Rays

What Are X-Rays?

We can define X-Rays or X-radiation as a form of electromagnetic radiation. They are powerful waves of electromagnetic energy. Most of them have a wavelength ranging from 0.01 to 10 nanometres, corresponding to frequencies in the range 3 × 10¹⁹ Hz to 3×10¹⁶ Hz and energies in the range 100 eV to 100 keV.

Who invented the X-Ray?

German physicist Wilhelm Röntgen is typically credited for the discovery of X-Rays in 1895 because he was the first to comprehensively study them, though he is not thought to be the first to have seen and perceived their effects.

They were found emanating from Crookes tubes, experimental discharge tubes invented around 1875, by scientists looking into the cathode rays, that is energetic electron beams, that were first formed in the tubes.

How Do X-Rays work?

They are produced when high-velocity electrons collide with the metal plates, thereby giving the energy as the X-Rays and themselves absorbed by the metal plate.

• The X-Ray beam travels through the air and comes in contact with the body tissues, and produces an image on a metal film.
• Soft tissue like organs and skin, cannot absorb the high-energy rays, and the beam passes through them.
• Dense materials inside our bodies, like bones, absorb the radiation.
  
  
  

Properties of X-ray

·        X-rays are electromagnetic radiations that move at the speed of light () in a straight line.

·        They are extremely penetrating rays that can penetrate a variety of materials that are opaque to conventional light.

·        They ionise the gas they travel through. They knock off electrons from many neutral atoms as they move through the atmosphere, leaving these atoms with a positive charge.

·        Fluorescence is caused by them in a variety of materials. When exposed to X-rays, a plate covered with barium platinocyanide, ZnS, or other materials glows.

·        They have an impact on photographic plates.

·        Electric and magnetic forces do not deflect them, indicating that they are not charged particles.

·        Except for refraction, they display all of the characteristics of waves. When passed through a crystal that acts like a grant, they produce diffraction patterns.

Applications of X-ray

X-rays are crucial and useful in surgery, medicine, engineering, and crystal structure research.

1. Scientific Applications:

Diffraction of X-rays at crystals gave X-ray crystallography a whole new dimension. The interior structure of crystals is determined using a variety of diffraction patterns. Bragg's Law may be used to precisely calculate the spacing and locations of atoms in a crystal.

2. Industrial Applications:

X-rays are employed in industry to identify faults in metallic constructions of large machinery, railway tracks, and bridges since they can penetrate many materials. The composition of alloys and pearls is studied using X-rays.

3. Radiotherapy:

X-rays have the potential to harm the body's tissues (cells are ionised and molecules are broken). When employed at proper and controlled intensities, X-rays harm malignant growths such as cancer and tumours, which are life-threatening.

4. Medicine and Surgery:

Heavy elements absorb more X-rays than lighter elements. Because bones absorb more X-rays than the tissues around them. On the photographic plate, their shadow is cast. As a result, bone breaks or fractures may be easily identified. X-rays can also reveal abnormalities in the bowel and digestive tract.

 

GAMMA – RAY

Gamma radiation, also known as gamma rays, is a type of electromagnetic radiation with extremely high energy and short wavelengths. It belongs to the electromagnetic spectrum, which includes various forms of radiation such as radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.

Here are some key points about gamma radiation:

1. Nature: Gamma radiation consists of high-energy photons that are emitted from the atomic nucleus during certain nuclear processes. Unlike alpha and beta particles, which are charged particles emitted during radioactive decay, gamma rays are neutral and carry no electrical charge.
2. Energy and Penetration: Gamma rays have the highest energy and shortest wavelength among the electromagnetic spectrum. They can penetrate various materials, including human tissue and dense objects like lead and concrete. The penetration ability of gamma radiation makes it useful in industrial applications and medical imaging.
3. Sources of Gamma Radiation: Gamma radiation can originate from different sources, including:

a. Natural Sources: Certain radioactive isotopes found in rocks, soil, and the atmosphere can emit gamma rays. For example, potassium-40 and radon-222 are natural sources of gamma radiation.

b. Man-Made Sources: Gamma rays are also produced in various technological applications, such as in nuclear power plants, nuclear medicine (diagnostic and therapeutic procedures), industrial radiography, and radiation therapy for cancer treatment.

4. Interaction with Matter: When gamma rays interact with matter, three main processes occur:

a. Absorption: Gamma rays can be absorbed by matter, and the extent of absorption depends on the material's density and composition. The absorption of gamma rays can result in the ionization and excitation of atoms in the material.

b. Scattering: Gamma rays can undergo scattering, where they change direction after colliding with atoms or subatomic particles. This process can provide valuable information about the composition and structure of the material being examined.

c. Penetration: Gamma rays can also pass through matter without any significant interaction. This property enables them to be used in radiographic imaging and non-destructive testing to examine the internal structure of objects or materials.

 

RADIATION SAFETY

Radiation safety is the practice of minimizing the risks associated with exposure to ionizing radiation. It involves implementing safety measures, guidelines, and regulations to protect individuals, workers, patients, and the general public from the harmful effects of radiation. Here are some key points to consider regarding radiation safety:

1. Types of Radiation: Radiation can be classified into two main categories: ionizing radiation and non-ionizing radiation. Ionizing radiation, which includes gamma rays, X-rays, and certain particles, has sufficient energy to remove tightly bound electrons from atoms and molecules, leading to potential biological damage. Non-ionizing radiation, such as radio waves, microwaves, and visible light, has lower energy and is generally considered less harmful.
2. Regulation and Standards: Governments and regulatory bodies establish radiation safety standards and guidelines to ensure the safe use of radiation. These regulations cover areas such as radiation protection, occupational exposure, medical practices, and public exposure limits. Compliance with these standards helps protect workers, patients, and the public from excessive radiation exposure.
3. ALARA Principle: ALARA stands for "As Low As Reasonably Achievable." This principle guides radiation safety practices, emphasizing the importance of minimizing radiation exposure to the lowest practical level without compromising the intended purpose of the radiation application. It involves employing techniques, technologies, and procedures to reduce radiation doses and potential risks.
4. Radiation Monitoring: Regular monitoring of radiation levels is crucial in radiation safety programs. This includes measuring radiation exposure in various areas, such as workplaces, medical facilities, and public environments, using dosimeters, radiation detectors, and monitoring equipment. Monitoring ensures that radiation levels remain within acceptable limits and helps identify areas requiring additional protection.
5. Shielding and Containment: Shielding and containment measures are implemented to prevent or minimize radiation exposure. This involves the use of lead, concrete, or other radiation-absorbing materials to create barriers that attenuate radiation. Shielding is crucial in medical facilities, nuclear power plants, industrial settings, and transportation of radioactive materials to protect workers, the public, and the environment.
6. Training and Education: Proper training and education play a vital role in radiation safety. Individuals working with or around radiation sources should receive comprehensive training on radiation hazards, safety procedures, handling techniques, and emergency protocols. Education promotes awareness, understanding, and adherence to radiation safety practices, reducing the risks associated with radiation exposure.
7. Personal Protective Equipment (PPE): Personal protective equipment, such as lead aprons, gloves, goggles, and thyroid shields, is used to reduce radiation exposure to specific body parts during procedures involving ionizing radiation. The appropriate use of PPE helps protect workers and patients from unnecessary radiation exposure.
8. Risk Communication: Effective communication regarding radiation risks is essential in radiation safety. This includes informing individuals about potential radiation hazards, precautions, and safety protocols. Communicating risks clearly and transparently helps individuals make informed decisions and fosters trust in radiation safety practices.
9. Emergency Preparedness: Preparedness for radiation emergencies is crucial for minimizing the impact of accidental radiation releases or incidents. Emergency plans, procedures, and training should be in place to ensure prompt and effective responses to potential radiation emergencies.