Frequently Asked Questions
How safe is CXR’s real-time x-ray inspection equipment? Do we need to worry about radiation?
CXR’s x-ray inspection systems are extremely safe and use only low-level x-ray sources. The equipment is designated Cabinet X-Ray by the FDA is permitted to emit no more than 0.5 milliroentgen per hour at any point five centimeters from the external surface. This is the same specification to which carry-on luggage x-ray inspection systems at airports are required to submit. CXR’s equipment is well within all required limits.
Radiation exposure decreases by a factor of 2 for every additional inch away from the machine’s surface. (Formula = 1/distance squared) For example, if you stand 1 inch (approximately 5 centimeters) from the machine you will receive at most .5 MR/hour (.5 ÷ 1 squared). If you stand 2 inches from the machine, you will receive at most .13 MR/ hour (.5 ÷ 2 squared). If you stand 6 inches from the machine, you will receive at most .01 MR/hour (.5 ÷ 6 squared) which is the same as normal, natural background radiation.
The FDA's Radiation - Emitting Products FAQ page states the following:
Manufacturers are required to certify that their products meet the Federal radiation safety performance standard for cabinet x-ray systems. Specifically, the standard requires that the radiation emitted from a cabinet x-ray system not exceed an exposure of 0.5 milliroentgens in one hour at any point five centimeters from the external surface. Most cabinet x-ray systems emit less than this limit. In addition, the standard also requires safety features that include warning lights, warning labels, and interlocks.
For comparison, the average person in the United States receives a dose of about 360 millirem of radiation per year from background radiation. (Note: 1 milliroentgen of exposure to x-rays will result in approximately 1 millirem of dose.) Background radiation is radiation that is always present in the environment. Eighty percent of that exposure comes from natural sources: radon gas, the human body, outer space, rocks, and soil. The remaining 20 percent comes from man-made radiation sources, primarily medical x rays.
What are the allowable occupational radiation exposure limits set by the government and is CXR’s equipment in compliance with them?
According to Government Regulations, 10 CFR 20, allowable occupational radiation exposure limits are 5,000 MR/year for whole body (head, trunk, arms above the elbow, legs above the knee) and 50,000 MR/year for extremities (hands, elbows, arms below the elbows, foot, knee or leg below the knee.)
CXR’s x-ray inspection equipment emits no more that .5 MR/hour at five centimeters, or one inch, from any surface of the machine. If an employee should stand 1 inch away from the unit for 8 hours a day for a working year of 200 days, s/he would receive, at most, 800 MR/year which is less than 20% of the allowed maximum. CXR’s x-ray inspection systems are safe and in compliance with all government regulations.
How does CXR Company determine that any radiation emissions from the x-ray inspection systems are within allowable limits?
CXR closely monitors for radiation to be certain we are staying well within safe limits. The x-ray inspection machines are tested for radiation emissions using a certified Ludlum radiation meter every time they are set up, whether at our plant or a customer’s plant. In this way we are certain to emit no greater than the .5 MR/ hour limit. In addition, customer employees working with our equipment are provided with radiation dosimeters to monitor any radiation exposure even though federal regulations do not require us to provide these. CXR technicians train customer employees in the proper use and reading of dosimeters.
Are CXR’s x-ray inspection systems safe for our product? Will it irradiate our product?
CXR’s x-ray machines are safe for your product. Government Regulations 21 CFR 179.21 state that, for cabinet x-ray, no food shall be exposed to radiation sources so as to receive an absorbed dose in excess of 10 grays. CXR’s x-ray inspection machines are well within these established limits. Our equipment is designed to inspect products for foreign particle contaminants, product defects, etc. We do not perform irradiation, or sterilization, of your product.
As stated on the FDA's Radiation- Emitting Products FAQ Page:
The radiation dose typically received by objects scanned by a cabinet x-ray system is 1 millirad or less. The average dose rate from background radiation is 360 millirad per year. The minimum dose used in food irradiation for food preservation or destruction of parasites or pathogens is 30,000 rad.
