Guidelines for Diagnostic X-Ray Procedures

The purpose of this document is to assist facilities that possess radiation-emitting equipment in establishing diagnostic x-ray safety procedures as required by the Iowa Radiation Machines and Radioactive Materials Rules. It should be noted that these are only guidelines and each facility must establish specific procedures consistent with its own method of operation. The objective of these safety procedures is to minimize radiation exposure to the patients, staff, and general public and to produce the best x-ray image possible with minimal radiation exposure.

Sample Guidelines

Except for patients who cannot be moved out of the room, only the staff and ancillary personnel required for the medical procedure or training shall be in the room during the radiographic exposure. Other than the patient being examined:

All individuals shall be positioned such that the useful beam will strike no part of the body unless protected by 0.5 millimeter lead equivalent.
Staff and ancillary personnel shall be protected from the direct scatter radiation by protective aprons or whole body protective barriers of not less than 0.25 millimeter lead equivalent.
Human patients who cannot be removed from the room shall be protected from the direct scatter radiation by whole body protective barriers of 0.25 millimeter lead equivalent or shall be so positioned that the nearest portion of the body is at least 2 meters from both the tube head and the nearest edge of the image receptor.

Gonad shielding of not less than 0.50 millimeter lead equivalent shall be used for human patients, who have not passed the reproductive age, during radiographic procedures in which the gonads are in the useful beam, except for cases in which this would interfere with the diagnostic procedure.
Individuals shall not be exposed to the useful beam except for healing arts purposes and unless such exposure has been authorized by a licensed practitioner of the healing arts or a licensed registered nurse who is registered as an advanced registered nurse practitioner pursuant. This provision specifically prohibits deliberate exposure for the following purposes:

Exposure of an individual for training, demonstration, or other non-healing arts purposes; and
Exposure of an individual for the purpose of healing arts screening except as authorized by a Bureau approved healing arts screening program.

When a patient or film must be provided with auxiliary support during a radiation exposure:

Mechanical holding devices shall be used when the technique permits. The written safety procedures shall list individual projections where holding devices cannot be utilized;
Shall indicate the requirements for selecting a holder and the procedure that the holder shall follow;
The human holder shall be protected as stated in A.2. above;
No individual shall be used routinely to hold film or patients; and
In those cases where the human patient must hold the film, except during intraoral examinations, any portion of the body other than the area of clinical interest struck by the useful beam shall be protected by not less than 0.5 millimeter lead equivalent material.
Each facility shall have leaded aprons and gloves available in sufficient numbers to provide protection to all personnel who are involved with X-ray operations and who are otherwise not shielded.

Procedures and auxiliary equipment designed to minimize patient and personnel exposure commensurate with the needed diagnostic information shall be utilized.

The speed of film or screen and film combinations shall be the fastest speed consistent with the diagnostic objective of the examinations. Film cassettes without intensifying screens shall not be used for any routine diagnostic radiological imaging, with the exception of veterinary radiography and standard film packets for intra-oral use in dental radiography.
The radiation exposure to the patient shall be the minimum exposure required to produce images of good diagnostic quality.
Portable or mobile X-ray equipment shall be used only for examinations where it is impractical to transfer the patient(s) to a stationary X-ray installation.
X-ray systems other than fluoroscopic, intraoral, and CT shall not be utilized in procedures where the source to human patient distance is less than 30 centimeters.
If grids are used between the patient and the image receptor to decrease scatter to the film and improve contrast, the grid shall:

Be positioned properly, i.e., tube side facing the correct direction and the grid centered to the central ray;
If of the focused type, be at the proper focal distance for the SIDs being used.

All operators and other staff shall be instructed to remain in a specified protected area during exposures.

Determine if a woman is of childbearing age or might be pregnant. If pregnancy exists or may exist, establish whether the responsible doctor is aware of this fact and still consents to the examination at this time.
The registrant shall control the occupational dose to individual adults, except for planned special exposures to the following dose limits:

An annual limit, which is the more limiting of:

The total effective dose equivalent being equal to 5 rem (0.05 Sv); or the sum of the deep dose equivalent and the committed dose equivalent to any individual organ or tissue other than the lens of the eye being equal to 50 rem (0.5 Sv).

The annual limits to the lens of the eye, to the skin, and to the extremities which are:

An eye dose equivalent of 15 rem (0.15 Sv) and a shallow dose equivalent of 50 rem (0.5 Sv) to the skin or to any extremity.

Each registrant shall monitor occupational exposure to radiation and shall supply and require the use of individual monitoring devices by:

Adults likely to receive, in 1 year from sources external to the body, a dose in excess of 10 percent of the limits listed above, and
Minors and declared pregnant women likely to receive, in 1 year from sources external to the body, a dose in excess of 10 percent of any of the applicable limits for occupational workers, and
Individuals entering a high or very high radiation area.
Individuals working with medical fluoroscopic equipment.

Each licensee or registrant shall ensure that individuals who are required to monitor occupational doses wear individual monitoring devices as follows:

An individual monitoring device used for monitoring the dose to the whole body shall be worn at the unshielded portion of the whole body likely to receive the highest exposure. When a protective apron is worn, the location of the individual monitoring device is typically at the neck (collar);
An individual monitoring device used for monitoring the dose to an embryo/fetus of a declared pregnant woman shall be located at the waist under any protective apron being worn by the woman;
An individual monitoring device used for monitoring the eye dose equivalent shall be located at the neck (collar), outside any protective apron being worn by the monitored individual, or at an unshielded location closer to the eye;
An individual monitoring device used for monitoring the dose to the extremities shall be worn on the extremity likely to receive the highest exposure. Each individual monitoring device shall be oriented to measure the highest dose to the extremity being monitored.

Fluoroscopic equipment shall be used only under the direct supervision of a licensed practitioner.
A technique chart shall be provided in the vicinity of the control panel which specifies kVp, mA, and time for all examinations performed. These factors should be typical for the specified part of the human body being radiographed and established to they provide the best possible x-ray image with the least radiation exposure. The chart should include the following:

Patient's anatomical size versus technique factors to be utilized;
Type and size of the film or film-screen combination to be used;
Type and focal distance of the grid to be used, if any;
Source to image receptor distance to be used, except for dental intraoral radiography;
Type and location of placement of human patient shielding to be used (gonadal).