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What image comes to your mind when you hear the word “radiation”? Most people think of a three-eyed fish and nuclear power plants. The word evokes a variety of reactions, but radiation is a topic often misunderstood. It’s true we should all be wary of radiation, but that doesn’t mean we should be worried about x-ray safety in product inspection. Read on while we explore what radiation is, refute some common myths and reveal some sizzling facts.
What is Radiation?
Radiation is energy emitted from a source. Like all forms of energy, radiation can be both useful and harmful to humans. For example, high levels of radiation can cause cancer as well as cure cancer.
Two main sources of radiation exist: natural and man-made. Natural radiation includes heat or light from the sun, radiation from the ground and gamma rays from radioactive elements. Man-made radiation includes microwaves from an oven and x-rays from an x-ray tube.
X-rays are a form of electromagnetic radiation. All types of electromagnetic radiation are part of a single continuum known as the electromagnetic spectrum. Ionizing radiation is radiation with enough energy to remove tightly bound electrons from the orbit of an atom, causing the atom to become charged or ionized. Not all electromagnetic radiation is ionizing. Only the high frequency portion of the electromagnetic spectrum is ionizing, which includes x-rays and gamma rays. Why is this important and why should you care? You’ll soon find out just how much ionized radiation we are exposed to in our day-to-day lives.
There’s No Escaping Radiation – it’s all around us!
Humans have been exposed to background radiation since the beginning of time and it’s all around us. Low levels of naturally-occurring radioactive material are in our environment, the food we eat, and in many consumer products. Natural sources of radiation account for approximately 82%² of the total radiation we receive. It’s impossible to eliminate radiation from our surrounding environment.
Did you know that bananas are slightly radioactive and eating one a day exposes you to ionizing radiation? Flying also increases levels of radiation. One flight from New York to London gives travelers about the same level of radiation as a chest x-ray. What’s more, frequent fliers absorb around 8% more radiation, compared to non-fliers¹. Don’t believe it? Read this white paper, ‘How Safe Is X-ray Inspection of Food?’ it shatters common misconceptions regarding x-ray food inspection and dispels a few myths as well.
X-ray systems are built to protect people
When radiation’s energy is deposited into our body’s tissues, we receive a dose of radiation. A Rem (Roentgen Equivalent Man) is a unit of effective absorbed dose of ionizing radiation in human tissue. Small doses are expressed in mRem (milliRem) or uRem (microRem) i.e. 1 Rem = 1000 mRem and 1 mRem = 1000 uRem.
Our average annual exposure to natural and man-made radiation is approximately 360 mRem/year. This far exceeds the radiation exposure received from a properly installed and maintained x-ray inspection machine.
X-ray systems used in the food and pharmaceutical industries don’t contain any sources of live radiation, such as uranium, and are designed with highly-dense materials to protect users from the effects of radiation. Actually, x-rays are electrically generated which means they can be turned on and off, plus cabinet system enclosures exist where the x-ray generator is installed as a safeguard.
Standard safety features should include tunnel curtains to retain emissions, a safety interlock design, and the x-ray system can also be fully integrated with the manufacturer’s production-line safety circuit if required. Other vital features should be lockable power isolators, accessible emergency stops, and a top-mounted lamp stack with 360° visibility.
The risk of being exposed to radiation can also be controlled through a series of x-ray safety principles:
- Time – minimizing your time in a radiation field
- Distance – maximizing your distance from a radiation source
- Shielding – x-rays are absorbed when they pass through a material. The most efficient absorbers of x-rays are highly-dense materials, which is why x-ray systems are often made from stainless steel. Some x-ray generators are designed with copper incorporated into it as an additional containment for the x-rays released.
In practice, operators spend very little time close to x-ray inspection equipment. Modern systems are automated to minimize operator involvement. The use of x-ray equipment for product inspection began around the early 1900’s and is both highly-regulated and increasingly common. That being said, x-ray inspection machines should be regularly tested and certified to meet safety standards—standards such as the Ionizing Radiation Regulations 1999 and the American Standard 1020.40 CFR. Trained operators must follow these safety guidelines to ensure a facility remains in compliance with regulatory standards.
Contrary to popular belief, modern x-ray systems provide a perfectly safe working environment for both the operators and the food product they inspect. They also help to detect hazardous contaminants that are missed by the human eye and strengthen quality assurance.
For more information on x-ray product inspection and its use in the food manufacturing industry read this white paper, ‘More Than Foreign Body Detection.’
X-ray Inspection Systems Don’t Change Food Quality
Food passing through an x-ray machine spends less than one second in the x-ray beam. During that brief time, the radiation dose it receives is so low even organic food has no diminution to its organic status. You can be sure that the food passing through an x-ray system is just as tasty to eat after it’s been scanned, as there are no measurable changes to flavors, textures or nutritional values. X-rayed food is indistinguishable to food that hasn’t been through an x-ray.
Scientific evidence from a 1997 study by the World Health Organisation (WHO) confirmed that radiation levels up to 10,000 Gy (a measurement of radiation) doesn’t affect food safety or nutritional value. 3 In fact, the dose of 10,000 Gy of radiation is approximately ten million times stronger than radiation used in x-ray inspection!
Leading food companies around the world use x-ray systems for contaminant detection. This is hardly surprising considering dose levels used in x-ray inspection of food are less than one ten millionth of those used in the WHO study. X-ray equipment wouldn’t be in operation if it didn’t serve a purpose. The real risk to human health comes from contaminants such as metal, glass, stone, and bone and x-ray inspection systems are used to detect and reject contaminated food from the production line. Since x-ray inspection is good at catching foreign bodies (and checking product integrity) without affecting the food or the people who operate the equipment, it’s fair to say that x-ray inspection is a force for improving food safety and quality, not reducing it.
If you are interested in a product analysis for your application or for more information on contaminant detection in food, email us at eaglesales@eaglepi.com.
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¹ http://listverse.com/2014/05/28/10-lesser-known-things-involving-radiation/
² The ionizing radiation exposure to the public is taken from the National Council on Radiation Protection and Measurements (NCRP Report No. 93), “Ionizing Radiation Exposure of the Population of the United States,” 1987.
