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When X-ray radiation from the handheld XRF (pXRF) instruments' X-ray tube excites the atoms in the sample, the atoms release fluorescent X-rays. The energy level of each fluorescent X-ray create is characteristic of the element excited. As ; as a result, one can tell what elements are present based on the energies of the X-ray emitted. The Olympus Delta pXRF detects and determines the fluorescent X-ray energies , produced. These energy patterns are characteristic to specific elements and allows for elemental measurements on section halves and discrete samples. However, as As the pXRF emits radiation (from 8-40keV), a comprehensive knowledge of radiation safety and procedures is needed.

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The term radiation is used with all forms of energy: light, X-rays, radar, gamma rays, microwaves, and more. However, for For the purpose of this manual, radiation refers to invisible waves or particles of energy emitted from a radioactive sources source or X-ray tubes.
Note: High levels of radiation may pose a danger to living tissue because they have the potential to damage and/or alter the chemical structure of cells. This could result in various levels of illness, ranging from mild to severe.

Types of Radiation

Radiation consists of invisible waves or particles of energy that, if received in too large a tube. Radiation if received in too large a quantity, can have an adverse health effect on humans. There are two distinct types of radiation: non-ionizing and ionizing.

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Ionizing Radiation

Ionizing radiation does have has enough energy to remove electrons from neutral atoms. Ionizing radiation is of concern due to its potential to alter the chemical structure of living cells. These changes can alter or impair the normal functions of a cell. Sufficient amounts of ionizing radiation can cause hair loss, blood changes, and varying degrees of illness.
There are four basic types of ionizing radiation, emitted from different parts of the atom (see Figure 1, below):

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Radiation Producing Devices

In the case of the pXRF, however, ingestion or inhalation is not an issue, because the X-the X-rays are generated by a cathode-ray tube. If current is applied to the tube in sufficient voltage (>8 kV) to generate X-rays, they are radiation is produced. If no current is flowing, no radiation is produced. Therefore, the pXRF is completely safe from a radiation standpoint when it is unpowered.
Note: the pXRF emits only X-rays. For this reason, this manual will preferentially focus on x-rays from this point on.

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X-rays interact with matter and lose energy because of that interaction. Therefore, the best shielding materials are dense, such as concrete, steel, or even lead.

Hazard

Due to their range and penetrating ability, X-ray radiation primarily is considered an external hazard. In other words, X-rays are hazardous through the skin, unlike alpha particles which are stopped by the skin.
Note: The absorption of radiation into the body, or anything else, depends upon two things; the type of radiation involved and the amount of radiation energy received. The units for measuring radiation are the roentgen, rad and rem: i.e. they're hazardous through the skin.

Biological Effects of Radiation

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