Roentgen definition

Roentgen means the special unit of exposure. One roentgen (R) equals 2.58 × 10-4 coulombs/kilogram of air (see “Exposure” and 38.4(4)).
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Roentgen. (R) means the special unit of exposure. One roentgen equals 2.58 x 10-4 coulombs/kilogram of air.
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Roentgen or “R” means the special unit of exposure. One roentgen equals 2.58E−4 coulombs per kilogram of air.
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Examples of Roentgen in a sentence

  • For example, a measured entrance exposure of 0.50 Roentgen from a Mo/Mo Target Filter system at 30 kVp with a measured HVL of 0.36-mm aluminum yields an average glandu- lar dose of (0.50 R) × (174 mrad/R) = 87 mrad or 0.87 mGy.*Wu X.

  • RULE 41.6(136C)—APPENDIX IRescinded IAB 4/5/00, effective 5/10/00RULE 41.6(136C)—APPENDIX IIGlandular Dose (in mrad) for 1 Roentgen Entrance Exposure4.5-cm Breast Thickness—50% Adipose/50% Glandular Breast Tissue* To convert from entrance exposure in air in Roentgen to mean glandular breast dose in millirads, multi- ply the entrance exposure by the factor shown in the table for the appropriate kVp and beam quality (HVL) combination.

  • A) The system shall be capable of producing a min- imum output of 4.5 mGy air kerma per second (513 milli Roentgen (mR) per second) when operating at 28 kVp in the standard mammography (moly/ moly) mode at any SID where the sys- tem is designed to operate and when measured by a detector with its center located 4.5 cm above the breast support surface with the compression paddle in place between the source and the detec- tor.

  • The exposure rate due to transmission through the primary protective barrier with the attenuation block in the useful beam, combined with radiation from the image intensifier, shall not exceed 2 milliRoentgen (0.516 uC/kg) per hour at 10 centimeters from any accessible surface of the fluoroscopic imaging assembly beyond the plane of the image receptor for each Roentgen per minute of entrance exposure rate.

  • From a Cs-137 or Co-60 source, which are gamma emitters, the exposure rate in μSv/h (mR/hr) can be read directly from a calibrated meter.Most meters are still calibrated in the traditional unit of Roentgen, more than likely in milliroentgens (mR) or microroentgens (μR).


More Definitions of Roentgen

Roentgen means the special unit of exposure. One roentgen (R) equals 2.58E-4 coulombs per kilogram of air (see "Exposure" and 12VAC5-481-240).
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Roentgen. (R) means the special unit of EXPOSURE. One roentgen equals 2.58 x 10 to the -4 power coulombs per kilogram of air. See EXPOSURE.
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Roentgen means the amount of gamma or x-rays required to produce ions resulting in a charge of 0.000258 coulombs per kilogram of air under standard conditions.
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Roentgen means the special unit of exposure. One roentgen (R) equals 2.58E-4 coulomb per kilogram of air (see "Exposure" and 1.1.15).
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Roentgen means the special unit of exposure. One roentgen (R) equals 2.58E-4 coulombs per kilogram of air [See "Exposure" and 420-3-26-.03(13)].
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Roentgen. (R) means the special unit of exposure and is equal to the quantity of x or gamma radiation which causes ionization in air equal to 258 microcoulomb per kilogram (see “Exposure”).
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Roentgen means the special unit of exposure. One roentgen (R) equals 2.58 x 10-4 coulombs per kilogram (C/kg). (See "Exposure" and Section 310.140 of this Part.)
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