The role of the metal detector
Apart from the cost implication of installing a new inspection system, the main reason behind the enduring prevalence of metal detectors is that, for many manufacturers, they remain an effective “first line of defense”. If there is minimal risk of non-metallic contamination in the product, a metal detector will consistently and accurately identify the most likely foreign bodies – swarf, filings, nuts, bolts, etc. Similarly, due to more rigorous demands from their customers and legislation, many pharmaceutical processors require inspection systems at various points on their production lines.
Often these will be early on, for incoming ingredients; after mixing / immediately prior to primary packing; and just before dispatch.
Fear of the unknown
Some manufacturers, whose processes are suited to x-ray inspection, have concerns over installing new equipment. There is a relatively widespread, although unfounded, perception that x-ray systems are difficult to set up and operate due to far more complex technology. However, x-ray technology is 
surprisingly simple – the machine looks for objects that are denser than the surroundingproduct. With a highly intuitive user interface and touch screens, the equipment is also very easy to navigate. The safety of the equipment is also a subject of discussion when considering x-ray inspection systems. X-ray beams (which are electromagnetic rays, as are microwaves and visible light) are contained within the machine and do not pose any risk to human health or safety. No protective clothing or equipment is required and no impact on health has been found among operators who have used x-ray machines for extended periods of time.
Installing the right inspection equipment
The choice of inspection equipment is based on many variables, including the potential contaminants, the product itself, its packaging material, the physical space available and of course, budget. As a result, it is advisable to speak with suppliers who offer a range of solutions rather than only one product. It is not uncommon for manufacturers to have three or four different machines installed at different positions on the line. A gravity fall metal detector or pipeline x-ray machine to inspect incoming 
raw materials may be followed by a vertical packaging detector between weighing and bagging. Then, after a checkweigher, an x-ray machine or metal detector may be employed to conduct a final check on the case-packed product.
Starting to work with x-ray
There is no doubt that x-ray inspection has considerable advantages in many pharmaceutical processing environments. Easy to install, safe and simple to use, even without previous experience, x-ray offers comprehensive contaminant detection and much more. It quickly and consistently identifies substandard products, reducing product recall, customer returns and complaints, therefore protecting manufacturers’ brands. Furthermore x-ray helps to demonstrate due diligence, complies with HACCP, industry standards and legislation, retailers’ QC requirements and national and international regulations. The use of x-ray can improve customer confidence, satisfaction and retention and assist in the generation of new business. With all these benefits on offer, and reassurance about installing and using x-ray systems, the future is looking bright for this innovative and exciting technology.
Compared to other inspection equipment, x-ray is relatively immune to product effects and similar physical interactions, including:
• The effects of metallised film and foil packaging.
• The presence of metallic items such as premium inserts, pouring spouts, clips, etc.
• The effects of conductivity or polarised molecules.
• Temperature - products can be inspected at temperatures between -20°C and +90°C.
• Vibrations from surrounding equipment.
• The proximity of metallic objects, magnetic fields or conductive materials
rubber, stone or plastic which could not be identified by traditional inspection methods. A further benefit of x-ray is its ability to carry out other types of inspection, including component counting, the identification of misshapen parts, mass and zoned mass verification, fill level control and seal integrity inspection as well as the detection of the presence of instruction leaflets in for example blister packs.