Ohio Administrative Code
Title 3701:1 - Radiation Control
Chapter 3701:1-67 - External Beam Radiation Therapy Equipment
Section 3701:1-67-05 - Standards for therapy equipment operating at less than one megavolt (MV)
Current through all regulations passed and filed through March 18, 2024
As used in this rule, "therapy equipment" means therapy equipment operating below one megavolt (MV). In addition to the rules in Chapters 3701:1-38 and 3701:1-67 of the Administrative Code, handlers of therapy equipment shall comply with the following:
(A) When the x-ray tube is operated at its maximum rated tube current for the maximum kilovoltage (kV), the leakage air kerma rate shall not exceed the value specified at the distance specified for that classification of therapy equipment.
(B) Permanent diaphragms or cones used for limiting the useful beam shall provide at least the same degree of attenuation as required for the tube housing assembly.
(C) Requirements for adjustable or removable beam limiting devices include:
(D) The filter system shall be so designed that:
(E) Requirements for tube immobilization include:
(F) The tube housing assembly shall be so marked that it is possible to determine the location of the source to within five millimeters, and such marking shall be readily accessible for use during calibration procedures.
(G) Contact therapy tube housing assemblies shall have a removable shield of material, equivalent in attenuation to 0.5 millimeters of lead at one hundred kV, which can be positioned over the entire useful beam exit port during periods when the beam is not in use.
(H) A suitable irradiation control device shall be provided to terminate the irradiation after a pre-set time interval.
(I) The control system, in addition to the displays required by other provisions in this rule, shall have:
(J) When a control system may energize more than one x-ray tube:
(K) There shall be a means of determining the central axis target-to-skin distance (TSD) to within one centimeter and of reproducing this measurement to within two millimeters thereafter.
(L) Unless it is possible to bring the x-ray output to the prescribed exposure parameters within five seconds after the x-ray "on" switch is energized, the beam shall be attenuated by a shutter. In addition, after the unit is at operating parameters, the shutter shall be controlled by the operator from the control panel. An indication of shutter position shall appear at the control panel.
(M) Therapy equipment having a beryllium or other low-filtration window shall be clearly labeled as such upon the tube housing assembly and shall be provided with a permanent warning device on the control panel that is activated when no additional filtration is present, to indicate that the dose rate is very high.
Effective: 3/1/2016
Five Year Review
(FYR) Dates: 11/10/2015 and
11/15/2020
Promulgated
Under: 119.03
Statutory
Authority: 3748.04
Rule
Amplifies: 3748.01,
3748.02,
3748.04,
3748.05,
3748.06,
3748.07,
3748.12,
3748.121, 378.13,
3748.14,
3748.15,
3748.17,
3748.18,
3748.19,
3748.20,
3748.22,
3748.99
Prior
Effective Dates: 2/15/2001, 9/1/05, 1/14/11,
6/1/13