Radiation Safety - Revision history

Sbalak: Sbalak moved page Internal:Radiation Safety to Radiation Safety over redirect: Requested by Ingo

2025-12-04T20:30:05Z

Sbalak moved page Internal:Radiation Safety to Radiation Safety over redirect: Requested by Ingo

← Older revision

Revision as of 16:30, 4 December 2025

Rtang: Rtang moved page Radiation Safety to Internal:Radiation Safety over redirect: Requested by Ingo

2023-10-23T17:58:47Z

Rtang moved page Radiation Safety to Internal:Radiation Safety over redirect: Requested by Ingo

← Older revision

Revision as of 13:58, 23 October 2023

Rtang: /* Accelerated Ion Beam */

2023-10-16T18:44:41Z

Accelerated Ion Beam

← Older revision		Revision as of 14:44, 16 October 2023
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	== Sources of Radiation in the Experimental Areas ==		== Sources of Radiation in the Experimental Areas ==
	=== Accelerated Ion Beam ===		=== Accelerated Ion Beam ===
	One source of radiation is the accelerated ion beam, or rather, the nuclear reactions produced when the beam strikes various objects. The effective sources are therefore the various slits, apertures, beam stops, magnets boxes along the path of the beam, and finally the experimenters target chamber. Because large fractions of the ion beam are usually rejected at the entrance and exit slits of the ~~90◦~~ magnet, these are usually the strongest sources. The intensity of radiation from a small source (such as a set of slits) fall off with distance according to the “inverse square law” – often the radiation level measured against a set of slits may be quite high, but is negligible a few feet away.		One source of radiation is the accelerated ion beam, or rather, the nuclear reactions produced when the beam strikes various objects. The effective sources are therefore the various slits, apertures, beam stops, magnets boxes along the path of the beam, and finally the experimenters target chamber. Because large fractions of the ion beam are usually rejected at the entrance and exit slits of the 90<sup>◦</sup> magnet, these are usually the strongest sources. The intensity of radiation from a small source (such as a set of slits) fall off with distance according to the “inverse square law” – often the radiation level measured against a set of slits may be quite high, but is negligible a few feet away.

	This beam-induced radiation consists mainly of fast neutrons and gamma-rays, and is properly detected with a neutron monitor and Geiger-counter respectively. Although often the radiation will be emitted roughly equally in all directions from the object being bombarded, in some cases the neutron radiation will be much stronger in the directions close to that of the ion beam, that is the neutrons are “forward peaked”. In general, because of their greater penetrating power, and because of their greater biological effectiveness, neutrons pose the greater hazard.		This beam-induced radiation consists mainly of fast neutrons and gamma-rays, and is properly detected with a neutron monitor and Geiger-counter respectively. Although often the radiation will be emitted roughly equally in all directions from the object being bombarded, in some cases the neutron radiation will be much stronger in the directions close to that of the ion beam, that is the neutrons are “forward peaked”. In general, because of their greater penetrating power, and because of their greater biological effectiveness, neutrons pose the greater hazard.

	The amount of radiation produced depends on the type of beam, the beam energy, the beam current and on the material being bombarded, and so obviously varies greatly from experiment to experiment. In general, however, one can expect the radiation to increases as the beam energy increases and as the mass of the ion decreases. For example, the first Linac run used a ∼20 nA ~~29Si~~ beam at 95 MeV. Except near slits, the beam induced radiation was undetectable using the Geiger counter and neutron monitor. By contrast, a high-current 6Li or proton beam could produce levels of around 100 mREM/h.		The amount of radiation produced depends on the type of beam, the beam energy, the beam current and on the material being bombarded, and so obviously varies greatly from experiment to experiment. In general, however, one can expect the radiation to increases as the beam energy increases and as the mass of the ion decreases. For example, the first Linac run used a ∼20 nA <sup>29</sup>Si beam at 95 MeV. Except near slits, the beam induced radiation was undetectable using the Geiger counter and neutron monitor. By contrast, a high-current 6Li or proton beam could produce levels of around 100 mREM/h (= 1 mSv/h).

	'''Procedures''': A beacon on the switching magnets in either Target-room 1 or Target-room 2 will flash whenever there is an ion beam in the experimental hall (the beacon will come on when BS-1 or BS-2, respectively are open).		'''Procedures''': A beacon on the switching magnets in either Target-room 1 or Target-room 2 will flash whenever there is an ion beam in the experimental hall (the beacon will come on when BS-1 or BS-2, respectively are open).
	# When a beam is being run in the Linac area, the doors to the hallway will be locked from the inside, independent of the radiation levels. All access will be through the control room and target room 1 and is to be controlled by the accelerator operator.		# When a beam is being run in the Linac area, the doors to the hallway will be locked from the inside, independent of the radiation levels. All access will be through the control room and target room 1 and is to be controlled by the accelerator operator.
	# Once an experiment is running, a radiation survey will be carried out. If the radiation exceeds 2.0 mREM/h, access to the experimental area is prohibited, the access doors to the Tandem, Target Room 1 and the Linac Hall/Target Room 2 will be closed and the door interlock will be activated while the beam is delivered.		# Once an experiment is running, a radiation survey will be carried out. If the radiation exceeds 2.0 mREM/h ( = 20 uSv/h), access to the experimental area is prohibited, the access doors to the Tandem, Target Room 1 and the Linac Hall/Target Room 2 will be closed and the door interlock will be activated while the beam is delivered.

	=== Activated Material ===		=== Activated Material ===

Rtang: /* Radiation Doses and Dosimetry */

2023-10-16T18:42:36Z

Radiation Doses and Dosimetry

← Older revision		Revision as of 14:42, 16 October 2023
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	The dose limit for access to radiation areas at the Tandem-Linac lab is set at 2.0 mREM/h = 20 uSv/h.		The dose limit for access to radiation areas at the Tandem-Linac lab is set at 2.0 mREM/h = 20 uSv/h.
	However, there is no reason for anyone in the Tandem-Linac lab to receive even a small fraction of this dose. In fact, except under exceptional circumstances no one should need to receive a dose above the detection threshold of the film badge, namely 20 mRem (200 uSv) (the rough equivalent of a chest x-ray) in any quarter.		However, there is no reason for anyone in the Tandem-Linac lab to receive even a small fraction of this dose. In fact, except under exceptional circumstances no one should need to receive a dose above the detection threshold of the film badge, namely 20 mRem (200 uSv) (the rough equivalent of a chest x-ray) in any quarter.

			A very helpful radiation chart is here: https://xkcd.com/radiation/

	== Apply for a Dosimeter ==		== Apply for a Dosimeter ==

	https://safety.fsu.edu/form/dosimetry.php		https://safety.fsu.edu/form/dosimetry.php

Rtang: /* Radiation Doses and Dosimetry */

2023-10-16T18:41:50Z

Radiation Doses and Dosimetry

← Older revision		Revision as of 14:41, 16 October 2023
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	== Radiation Doses and Dosimetry ==		== Radiation Doses and Dosimetry ==
	Radiation Dose: The statutory limit for “radiation workers” – anyone with a film badge, over 18, and not pregnant, is a dose of 1.25 REM per quarter. This is the dose you would receive if while you were at work, you were continuously exposed to a radiation level of 2.5 milliREM per hour throughout the 500 working hours of the quarter:		Radiation Dose: The statutory limit for “radiation workers” – anyone with a film badge, over 18, and not pregnant, is a dose of 1.25 REM (12.5 mSv) per quarter. This is the dose you would receive if while you were at work, you were continuously exposed to a radiation level of 2.5 milliREM (25 uSv) per hour throughout the 500 working hours of the quarter:

	2.5 mREM/h * 500 h = 1.25 REM = 12.5 mSv		2.5 mREM/h * 500 h = 1.25 REM = 12.5 mSv

	The dose limit for access to radiation areas at the Tandem-Linac lab is set at 2.0 mREM/h.		The dose limit for access to radiation areas at the Tandem-Linac lab is set at 2.0 mREM/h = 20 uSv/h.
	However, there is no reason for anyone in the Tandem-Linac lab to receive even a small fraction of this dose. In fact, except under exceptional circumstances no one should need to receive a dose above the detection threshold of the film badge, namely 20 mRem (the rough equivalent of a chest x-ray) in any quarter.		However, there is no reason for anyone in the Tandem-Linac lab to receive even a small fraction of this dose. In fact, except under exceptional circumstances no one should need to receive a dose above the detection threshold of the film badge, namely 20 mRem (200 uSv) (the rough equivalent of a chest x-ray) in any quarter.

	== Apply for a Dosimeter ==		== Apply for a Dosimeter ==

	https://safety.fsu.edu/form/dosimetry.php		https://safety.fsu.edu/form/dosimetry.php

Rtang: /* Radiation Doses and Dosimetry */

2023-10-16T18:39:52Z

Radiation Doses and Dosimetry

← Older revision		Revision as of 14:39, 16 October 2023
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	Radiation Dose: The statutory limit for “radiation workers” – anyone with a film badge, over 18, and not pregnant, is a dose of 1.25 REM per quarter. This is the dose you would receive if while you were at work, you were continuously exposed to a radiation level of 2.5 milliREM per hour throughout the 500 working hours of the quarter:		Radiation Dose: The statutory limit for “radiation workers” – anyone with a film badge, over 18, and not pregnant, is a dose of 1.25 REM per quarter. This is the dose you would receive if while you were at work, you were continuously exposed to a radiation level of 2.5 milliREM per hour throughout the 500 working hours of the quarter:

	2.5 mREM/h * 500 h = 1.25 REM		2.5 mREM/h * 500 h = 1.25 REM = 12.5 mSv

	The dose limit for access to radiation areas at the Tandem-Linac lab is set at 2.0 mREM/h.		The dose limit for access to radiation areas at the Tandem-Linac lab is set at 2.0 mREM/h.

Rtang: /* Radiation Doses and Dosimetry */

2023-10-16T18:38:58Z

Radiation Doses and Dosimetry

← Older revision		Revision as of 14:38, 16 October 2023
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	The dose limit for access to radiation areas at the Tandem-Linac lab is set at 2.0 mREM/h.		The dose limit for access to radiation areas at the Tandem-Linac lab is set at 2.0 mREM/h.
	However, there is no reason for anyone in the Tandem-Linac lab to receive even a small fraction of this dose. In fact, except under exceptional circumstances no one should need to receive a dose above the detection threshold of the film badge, namely 20 mRem (the rough equivalent of a chest x-ray) in any quarter.		However, there is no reason for anyone in the Tandem-Linac lab to receive even a small fraction of this dose. In fact, except under exceptional circumstances no one should need to receive a dose above the detection threshold of the film badge, namely 20 mRem (the rough equivalent of a chest x-ray) in any quarter.

			== Apply for a Dosimeter ==

			https://safety.fsu.edu/form/dosimetry.php

Iwiedenhoever at 13:11, 30 September 2023

2023-09-30T13:11:46Z

← Older revision		Revision as of 09:11, 30 September 2023
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	3.b. For beams with Z>=4: Access to the Tandem Hall, the Linac Hall and/or the Target rooms is only allowed while the Gamma and Neutron dose rates in the area are below 2.0 mrem/h. Before access is granted to a given area, the radiation levels will be verified at the installed area radiation monitors and with portable gamma and neutron radiation monitors,		3.b. For beams with Z>=4: Access to the Tandem Hall, the Linac Hall and/or the Target rooms is only allowed while the Gamma and Neutron dose rates in the area are below 2.0 mrem/h. Before access is granted to a given area, the radiation levels will be verified at the installed area radiation monitors and with portable gamma and neutron radiation monitors,
	which are placed near the location where a person works. If radiation levels are above these limits, access to the areas is prohibited, all persons have to leave the affected areas and the operator in charge has to verify that no person remains in the areas before the doors are closed and the door interlock alarm in the control room is activated. The same rules as in 3.a apply in the case of access doors being opened.		which are placed near the location where a person works. Make entry to the log book with the results of the radiation levels and of the fact that access to the area was granted and to whom.
			If radiation levels are above these limits, access to the areas is prohibited, all persons have to leave the affected areas and the operator in charge has to verify that no person remains in the areas before the doors are closed and the door interlock alarm in the control room is activated. The same rules as in 3.a apply in the case of access doors being opened.

	4. In all cases, the Tandem HE shield door should be closed if a beam is being accelerated, independent of the radiation levels.		4. In all cases, the Tandem HE shield door should be closed if a beam is being accelerated, independent of the radiation levels.

Iwiedenhoever at 11:14, 27 September 2023

2023-09-27T11:14:38Z

← Older revision		Revision as of 07:14, 27 September 2023
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	alarms in the control room are activated. If a door is opened while the beam is present, the interlock system will automatically interrupt the beam at the LE end of the Tandem. The operator in charge will investigate the reason the doors were opened. Only after verifying that nobody is present in the protected area, the operator will close the affected door and re-activate the beam.		alarms in the control room are activated. If a door is opened while the beam is present, the interlock system will automatically interrupt the beam at the LE end of the Tandem. The operator in charge will investigate the reason the doors were opened. Only after verifying that nobody is present in the protected area, the operator will close the affected door and re-activate the beam.

	3.b. For beams with Z>=4: Access to the Tandem Hall, the Linac Hall and/or the Target rooms is only allowed while the Gamma and Neutron dose rates in the area are below 2.5 mrem/h. Before access is granted to a given area, the radiation levels will be verified at the installed area radiation monitors and with portable gamma and neutron radiation monitors,		3.b. For beams with Z>=4: Access to the Tandem Hall, the Linac Hall and/or the Target rooms is only allowed while the Gamma and Neutron dose rates in the area are below 2.0 mrem/h. Before access is granted to a given area, the radiation levels will be verified at the installed area radiation monitors and with portable gamma and neutron radiation monitors,
	which are placed near the location where a person works. If radiation levels are above these limits, access to the areas is prohibited, all persons have to leave the affected areas and the operator in charge has to verify that no person remains in the areas before the doors are closed and the door interlock alarm in the control room is activated. The same rules as in 3.a apply in the case of access doors being opened.		which are placed near the location where a person works. If radiation levels are above these limits, access to the areas is prohibited, all persons have to leave the affected areas and the operator in charge has to verify that no person remains in the areas before the doors are closed and the door interlock alarm in the control room is activated. The same rules as in 3.a apply in the case of access doors being opened.

	4. In all cases, the Tandem HE shield door should be closed if a beam is being accelerated, independent of the radiation levels.		4. In all cases, the Tandem HE shield door should be closed if a beam is being accelerated, independent of the radiation levels.

	5. If the Tandem is being conditioned and/or levels of X-rays above 2.5 mRem/h are observed on the Tandem Area x-ray monitor, the Tandem shield door has to be closed, the LE Shield door has to be locked and the door alarm has to be activated in the control room.		5. If the Tandem is being conditioned and/or levels of X-rays above 2.0 mRem/h are observed on the Tandem Area x-ray monitor, the Tandem shield door has to be closed, the LE Shield door has to be locked and the door alarm has to be activated in the control room.

	6. Any time a beam delivery is initiated into the Tandem, the Linac Hall or the Target rooms, the operator will announce the intent to inject beam into a new area through the laboratory intercom before injecting it.		6. Any time a beam delivery is initiated into the Tandem, the Linac Hall or the Target rooms, the operator will announce the intent to inject beam into a new area through the laboratory intercom before injecting it.
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	=== Tandem ===		=== Tandem ===
	The terminal and acceleration tubes near the terminal can be a strong source of x-rays, depending on the operating conditions (terminal voltage, beam current, etc.). Radiation levels at the tank wall near the terminal of 100 mREM/h are not uncommon.		The terminal and acceleration tubes near the terminal can be a strong source of x-rays, depending on the operating conditions (terminal voltage, beam current, etc.). Radiation levels at the tank wall near the terminal of 100 mREM/h are not uncommon.
	During Conditioning and whenever the radiation doses exceed 2.5 mRem/h, the Tandem access doors have to be closed and secured through the interlock alarm panel in the control room.		During Conditioning and whenever the radiation doses exceed 2.0 mRem/h, the Tandem access doors have to be closed and secured through the interlock alarm panel in the control room.

	=== Accelerated Ion Beam ===		=== Accelerated Ion Beam ===
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	'''Procedures'''		'''Procedures'''
	# Do not use the route past the H.E. end of the Tandem to access the Linac hall when there is a beam from the Tandem. If beam is being run in the Linac area, use the route through the target room 1. If beam is being run in the Target room 1, enter and exit the Linac through the door in the hallway.		# Do not use the route past the H.E. end of the Tandem to access the Linac hall when there is a beam from the Tandem. If beam is being run in the Linac area, use the route through the target room 1. If beam is being run in the Target room 1, enter and exit the Linac through the door in the hallway.
	# If radiation at the entrance to the H.E. end of the Tandem exceeds 2.5 mREM/h, the radiation door will be closed to prevent access.		# If radiation at the entrance to the H.E. end of the Tandem exceeds 2.0 mREM/h, the radiation door will be closed to prevent access.
	# If radiation at the entrance to the Target Room 1 area exceeds 2.5 mREM/h, the radiation door will be closed to prevent access.		# If radiation at the entrance to the Target Room 1 area exceeds 2.0 mREM/h, the radiation door will be closed to prevent access.

	== Sources of Ionizing Radiation In the Linac ==		== Sources of Ionizing Radiation In the Linac ==
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	'''Procedures''': A beacon on the switching magnets in either Target-room 1 or Target-room 2 will flash whenever there is an ion beam in the experimental hall (the beacon will come on when BS-1 or BS-2, respectively are open).		'''Procedures''': A beacon on the switching magnets in either Target-room 1 or Target-room 2 will flash whenever there is an ion beam in the experimental hall (the beacon will come on when BS-1 or BS-2, respectively are open).
	# When a beam is being run in the Linac area, the doors to the hallway will be locked from the inside, independent of the radiation levels. All access will be through the control room and target room 1 and is to be controlled by the accelerator operator.		# When a beam is being run in the Linac area, the doors to the hallway will be locked from the inside, independent of the radiation levels. All access will be through the control room and target room 1 and is to be controlled by the accelerator operator.
	# Once an experiment is running, a radiation survey will be carried out. If the radiation exceeds 2.5 mREM/h, access to the experimental area is prohibited, the access doors to the Tandem, Target Room 1 and the Linac Hall/Target Room 2 will be closed and the door interlock will be activated while the beam is delivered.		# Once an experiment is running, a radiation survey will be carried out. If the radiation exceeds 2.0 mREM/h, access to the experimental area is prohibited, the access doors to the Tandem, Target Room 1 and the Linac Hall/Target Room 2 will be closed and the door interlock will be activated while the beam is delivered.

	=== Activated Material ===		=== Activated Material ===
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	2.5 mREM/h * 500 h = 1.25 REM		2.5 mREM/h * 500 h = 1.25 REM

	However, there is no reason for anyone in the Tandem-Linac lab to receive even a small fraction of this dose. In fact, except under exceptional circumstances no one should need to receive a dose above the detection threshold of the film badge, namely 20 mRem (the rough equivalent of a chest x-ray) in any ~~month. This dose corresponds to spending 25 minutes, everyday, in a radiation field of 2.5 mREM/h~~.		The dose limit for access to radiation areas at the Tandem-Linac lab is set at 2.0 mREM/h.
			However, there is no reason for anyone in the Tandem-Linac lab to receive even a small fraction of this dose. In fact, except under exceptional circumstances no one should need to receive a dose above the detection threshold of the film badge, namely 20 mRem (the rough equivalent of a chest x-ray) in any quarter.

Iwiedenhoever: /* Accelerated Ion Beam */

2023-09-20T19:09:45Z

Accelerated Ion Beam

← Older revision		Revision as of 15:09, 20 September 2023
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	The amount of radiation produced depends on the type of beam, the beam energy, the beam current and on the material being bombarded, and so obviously varies greatly from experiment to experiment. In general, however, one can expect the radiation to increases as the beam energy increases and as the mass of the ion decreases. For example, the first Linac run used a ∼20 nA 29Si beam at 95 MeV. Except near slits, the beam induced radiation was undetectable using the Geiger counter and neutron monitor. By contrast, a high-current 6Li or proton beam could produce levels of around 100 mREM/h.		The amount of radiation produced depends on the type of beam, the beam energy, the beam current and on the material being bombarded, and so obviously varies greatly from experiment to experiment. In general, however, one can expect the radiation to increases as the beam energy increases and as the mass of the ion decreases. For example, the first Linac run used a ∼20 nA 29Si beam at 95 MeV. Except near slits, the beam induced radiation was undetectable using the Geiger counter and neutron monitor. By contrast, a high-current 6Li or proton beam could produce levels of around 100 mREM/h.

	'''Procedures''': A beacon on the switching magnets in either Target-room 1 or Target-room 2 will flash whenever there is an ion beam in the experimental hall (the ~~sign~~ will come on when BS-1 or BS-2, respectively are open).		'''Procedures''': A beacon on the switching magnets in either Target-room 1 or Target-room 2 will flash whenever there is an ion beam in the experimental hall (the beacon will come on when BS-1 or BS-2, respectively are open).
	# When a beam is being run in the Linac area, the doors to the hallway will be locked from the inside, independent of the radiation levels. All access will be through the control room and target room 1 and is to be controlled by the accelerator operator.		# When a beam is being run in the Linac area, the doors to the hallway will be locked from the inside, independent of the radiation levels. All access will be through the control room and target room 1 and is to be controlled by the accelerator operator.
	# Once an experiment is running, a radiation survey will be carried out. If the radiation exceeds 2.5 mREM/h, access to the experimental area is prohibited, the access doors to the Tandem, Target Room 1 and the Linac Hall/Target Room 2 will be closed and the door interlock will be activated while the beam is delivered.		# Once an experiment is running, a radiation survey will be carried out. If the radiation exceeds 2.5 mREM/h, access to the experimental area is prohibited, the access doors to the Tandem, Target Room 1 and the Linac Hall/Target Room 2 will be closed and the door interlock will be activated while the beam is delivered.