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Manufacturing supply chain
CHAPTER
Manufacturing supply chain
11
11.1 Introduction It is, without doubt, that the last thing most designers concern themselves about is how a device is going to be made. We saw, right at the very start of this book, that the best way to develop a device is to have the potential manufacturers in at the start. However, one still has to find them. This chapter concerns itself with the rigors of making, maintaining, and regulating your supply chain. Notice this chapter leads to infernal confusion e manufacturer. Under EC rules as the device specifier and holder of the CE mark you are the manufacturer; as you are are in the US (specification developer). However, this does not stop you from subcontracting aspects of the manufacturing process to someone else e but you must do this properly and within a framework.
11.2 Identifying potential suppliers Once again, your quality manual should have a procedure for purchasing. The first part of this purchasing procedure always contains the identification of suppliers. You will not be able to get away with purchasing items at random, under the medical devices regulatory framework you must name suppliers for all critical components/services. In the case of the FDA it is a part of the 510(k) submission, and changing a supplier may make your 510(k) invalid; and that is somewhere you do not want to go. There are no hard and fast regulations; but I can give you some rules to follow. There is no regulation that states who you must, but common sense should suggest that you do, use a supplier who already provides components and services in your classification. Hence one would not, normally, use a company to make a class III (EC) device if they have only ever made items up to class I. Rule of manufacturing 1: Always use a supplier who has supplied items to others in your classification and that are similar in nature. Medical Device Design. https://doi.org/10.1016/B978-0-12-814962-1.00011-9 Copyright © 2020 Elsevier Ltd. All rights reserved.
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If you work with your supply chain you will find that obeying rule 1 is not difficult. All you need do is ask, most suppliers are more than happy to show off their portfolio of customers and products. Do not be afraid to ask the supplier for references e remember it is your job on the line not theirs! Identification of certification level is of paramount importance. If you are dealing with an ISO 9001 or ISO 13485 registered company then you know that their documentary trail is going to meet your needs to delegate the responsibility of quality auditing to their notified body. Rule of manufacturing 2: Always use an ISO9001 supplier as a minimum requirement.
It cannot be emphasized enough that Rule 2 will help you so much. Without this minimum certification requirement you will have to perform full audits of the company in question, yourself. This in turn means you must be a qualified external auditor (as we have met in previous chapters). Do you really want this added burden? You may if you are making a very high risk device, but for most companies audit by certification is more than adequate. Rule of manufacturing 3: For Class I measuring devices and above always look for ISO13485 certification or equivalent. Rule of manufacturing 4: For implants look for a history of implant manufacture. Rule of manufacturing 4(a): For implants you may want a quality system audit process that is “above and beyond” ISO134851
Rules 1e4 make perfect sense. They basically state that you should use someone who knows what they are doing. Do not be tempted to cut costs by dropping your own standards. The same rules can be applied to services too; e.g. Rule of manufacturing 5: For delivery of sterilization services use a recognized sterile service provider.
You may think this obvious, but some sterile packagers only provide a packaging service. Some pack and sterilize. Some will also design your pack, test it, then pack and sterilize. You MUST ensure they have the certificates and track record of the service you want. Rule of manufacturing 6: Do not forget the packaging.
1
I have known companies that have passed an ISO13485 audit with flying colors, but who fail a customer audit just a few weeks later.
11.2 Identifying potential suppliers
Rule 6 may seem simplistic, but can you imagine the situation where you have gone to all of the effort to manufacture a device that is free from animal by products only to find that someone has ordered bubble-wrap that is contaminated. Rule of manufacturing 7: Do not forget your obligation to provide the correct information.
Again, a simple rule but often overlooked. For every device you pack there will be a concurrent pack of the appropriate number of IFUs and other essential documents (labels, surgical technique, if required, etc.). Have you had them printed? Are they readily available? Are they the right ones? Where are the labels? Do not forget that the essential documentation is just as much a part of the manufacturing process as the device itself!
11.2.1 Samples Before you put any supplier on an approved suppliers list you should always obtain samples. This does not mean simply looking in a salesman’s briefcase and looking at sales specimens; it means getting them to make something from your device and then holding them to this quality when it goes into batch production. You may be asking why? The first point is that you want to ensure they can make the item to the quality you want. You will be amazed how the same drawing of a component can result in a variety of finishes; even if it is a complete drawing. The second reason is that any company can produce one excellent item; but can they produce 20 to 1000 excellent items. You can, the, use this sample as your check for the production runs. Another good reason for asking for samples is that in your quotation process you will find that suppliers have “sweet spots”. Some items they can produce with relative ease, because that is what they specialize in. These will be relatively cheap. Other items out of the “sweet spot” will cost more. And that is why Rule 1 is so important.
11.2.2 Initial audit Consider having is an initial audit just to ease your mind. This need not be a rigorous procedure but you should supply them with an audit plan (a list of things you wish to examine) and then write a brief report of this audit. You may be surprised by what you find; companies, who on paper, seem to be excellent can be a let-down when you actually get to the buildings. Do not forget to examine their own audit trail. Examples of things you should be looking for are: • • •
General cleanliness Paperwork following products Raw material quarantine procedures
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• •
Use of animal products. Tooling (potential cross-contamination)
As we have touched on earlier, the last point is of paramount importance. You MUST get a statement from the company that no animal products are used in their processes, if this is not forthcoming then you really should question their suitability as a supplier unless they are absolutely necessary.
11.2.3 Contractual arrangements Every regulatory body will expect you to have contracts detailing your subcontractors’ responsibilities.2 It is a truism that without these you will not survive an audit. The contracts need not be onerous but they must stipulate certain things: • • • • • • •
They will only make to your specification; They will not substitute materials without your written approval; They will not modify any of your part drawings; They will retain relevant documents for the prescribed period, or supply them to you for you to keep; They will supply a statement of conformity with each batch; They will not use animal by-products in any process, without your knowledge and consent; They will notify you, immediately, of any non-conformance or hazard that they become aware of that may impact on your devices.
And in addition. •
Be aware and be compliant with an unannounced audit.
In addition, of course, you will have your own performance-based criteria. Most importantly, this will need to be in the form of a contract. A simple letter to your suppliers will not do. To be complaint with the regulations, the document will need to be signed by the company acting as a supplier (to state they have received it), you will need to sign it (to state you have supplied it), and it needs to be dated. Both of you will need to keep copies!
11.2.3.1 Preparation for an unannounced audit Do not think this will not happen to you. All companies have an unannounced audit, and in the EU this can be once every three years. The unannounced audit can be at your site or at one of your critical suppliers’ sites. Because of this you need to ensure your suppliers have all of the documentary evidence an auditor will require.
2
Some of these subcontractors will be critical suppliers: their contracts/agreements would, therefore, be more stringent. However it is much better to just have one stringent agreement that you can supply as appropriate.
11.2 Identifying potential suppliers
The contract stated above is the bear minimum. They will be treated, in effect, as an extension of your company. Hence, if you state they are to keep records for you, then you better check that they do, and that they are in a form that an auditor would like to see. Do not fall into the trap of giving every suppler a copy of your technical documentation, this is NOT required. But make sure they do have up-to-date copies of drawings and specifications. If you think this is an issue why not just send a copy of what is required, i.e. a drawing, with the order. No confusion! However, it is not a bad idea to undertake an audit yourself at convenient intervals. At least, in this way, you can avoid the pitfalls of a “bad” unannounced audit e and when they are bad believe me they are bad!
11.2.4 Approved supplier register Once complete and satisfied the potential supplier becomes and approved supplier. This you need to record in an Approved Suppliers Register. The report should record the outcomes of the investigations described above, it should also contain the relevant quality certificates (which must be kept up to date). A typical register entry for a company may be as follows (Table 11.1). Obviously your register would contain all the relevant certificates and the suppliers list would be a aide-memoire for both annual supplier audits (if required) and certificate updates. You should include an audit of the register as a part of your annual internal audit process.
Table 11.1 Example layout for approved suppliers list. Part numbers
Company
Contact
Certification
Audit by
Report
Fred Smith Medical
James Machin 0485 755664 jm@ FSM.com John Brown jbrown@ JMB.com
ISO 13485 (expires Nov 2013)
Certificate Audit 14 Jan 2012
FSM1
X-101-1 100e0
ISO 9001 (Nov 2015) ISO 13485 (Nov 2015)
Certificate
JMB1
All sterile packs. Sterilisation services. Accelerated life tests for st. packs
JMB sterile packaging inc
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Note that this register has two further functions. The first is that it stops creative procurement staff purchasing items from the cheapest source only e this can play havoc with product quality. The second is that it is an information file for your design process e this file tells you “who is good at doing what” and hence who is the best person to bring in at the first stages of a design process. In small companies this is very easy, but when the company gets moderately large this type of information becomes invaluable. It is, after all, a simple contacts management system.
11.2.4.1 Critical suppliers It is, without doubt, you will be asked “who are your critical suppliers?”. This question arises due to the new EC requirement for unannounced audits (yes they can drop in to you or one of your suppliers at any time, unannounced, and charge you for the pleasure). Your suppliers must be aware of this and be fully supportive (or you will lose you certification at a stroke). However, not all of your suppliers will be critical. Some of them most definitely will, such as sterile packers and manufacturers of implantable items. In order for you to have a better idea the following selection process (Fig. 11.1).
Critical Subcontractor
Crucial Supplier
Are they producing a process or service to your specifications?
YES YES
Are they providing bespoke materials or equipment to your specification?
NO Add to list
Are the providing design or testing of the product?
YES
NO
Is their contribution a substaintial part of the product?
YES
NO
Not on list
FIG. 11.1 Discriminating a critical supplier from a generic supplier.
NO
11.3 Packaging
New supplier?
N
Procurement
Y Relevant certificates?
N
Abort
Y Audit required?
N
Order sample
Y Audit plan Conduct audit
N Satisfactory? Y Complete report, sign agreements, and file
FIG. 11.2 Example new supplier procedure.
11.2.5 Suggested procedure for supplier approval You must have a purchasing procedure to meet ISO 13485. We have met these earlier in the book, however Fig. 11.2 illustrates this section as a procedure.
11.3 Packaging Essentially packaging comes within two main criteria. There will always be some form of internal pack that protects the device and (if necessary) its sterility. The second is the outer case that is for transportation and storage. Your packaging selection protocol must encompass both aspects.
11.3.1 Sterile packaging Sterile packs tend to come in two forms, flexible wrapped and rigid blister. The flexible wrapped kind is the sort of packaging that you would see with any sterile wound dressing you would purchase from a chemist or drug store. This type of pack is reserved for relatively light objects such as adhesive dressings, small bone screws and giving sets. The blister pack is for heavier objects; ones whose shear bulk would damage the weaker wrappings of the former. For general use the sterile packaging would come single wrapped, that is there is only one seal between the device and the outside world. If, however, the device is going into a sterile environment then
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it would be double wrapped. The simple reason is that the inner pack will remain sterile and can be passed to a sterile operative. If it were single packed the packaging, itself, would be non-sterile and hence cannot be passed on to any one in the sterile field. For this reason, almost exclusively, all devices bound for the operating theater (OR) are double wrapped (Figs. 11.3 and 11.4).
FIG. 11.3 Some typical single wrapped sterile pouches. Courtesy Riverside Medical Packaging Ltd.
FIG. 11.4 A typical double wrapped sterile pouch for use in a sterile field. Courtesy Riverside Medical Packaging Ltd.
11.3 Packaging
Table 11.2 Example sterile packaging methods. Device Light/flexible Flexible wrapping
Heavy/complex shape Blister Pack Use
General/domestic Single or double wrapped
Sterile Field/OR Double wrapped
There is a range of materials from which the pouches can be made, some examples are (Table 11.2): • • • • •
63 gsm PeelPlus 1073B Tyvek 12/38 PET/PE 60 gsm Paper 12mu PET/9mu Foil/50mu Peel PE
But seek advice from a packaging specialist. The packaging will need protection from the real world, so the design of the outer carrier is of vital importance. Your package may have to travel thousands of miles before it is used and the sterile inner must get to its destination unharmed. For this reason the design of sterile packs is best left to those with the expertise and know how. Most medical devices journals have a directory of providers of this service, and of course the web is indispensable. However, follow the rules of approval described earlier. The packaging and sterilization will have to pass formal approval criteria. There are specific standards depending on your sterilization method. For example, the approval for the evaluation of devices sterilized by irradiation is controlled by ISO 11137; those by ethylene oxide ISO 11135; and ISO 17665 for steam sterilization. Your packaging must make the fact that the device is sterile patently clear (we shall see this later in labeling), it must also illustrate the sterilization method. But, in all cases the packaging will have to pass stringent tests, accelerated life tests and real time evaluations before it can be classed as a sterile packaged device. This evaluation is governed by ISO 11607. Note; your decision to be sterile or non-sterile packed should not be taken on a whim. The cost of producing a document proving your packaging and sterility regime is acceptable is high. It is not just the cost of the test, you could be scrapping up to 80 devices just to conduct the test and the cost of each item can mount up to a
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scary total. There is also the cost of maintenance; you will have to undertake regular evaluations proving your packaging is still acceptable (normally every three months) and again you may be scrapping many devices in the process. Hence your decision to go sterile must be based on good market intelligence and not just because it seems a nice thing to do. You must have better things to spend your money on.
11.3.2 Non-sterile packaging Once again it is highly likely that your device will have an inner and an outer. However your inner pack may be something quite special and could easily be a sterile pouch, as described above but just not sterilized. However take care that your non-sterile items do not look similar to sterile items e this is just too disastrous to contemplate. The benefit of this type of pouch is that all standard details can be pre-printed on the pouch itself. If your device is reusable and is to be steam sterilized then you may wish to consider the role of a sterilization case (Fig. 11.5). A sterilization case is a specifically designed tray, normally out of stainless steel or anodized aluminum, that retains your device whilst it is being washed and then steam sterilized. The whole tray, therefore, must contain your device and fit into standard washing machines and autoclaves. There are a number of specialist tray manufacturers who can design something special. Equally you can purchase one ‘off the peg’. However, as stated previously, you will have to prove that your device can be washed and sterilized in this tray . you cannot assume that is the case (Fig. 11.6).
FIG. 11.5 An example of a single wrapped non-sterile item. Courtesy Riverside Medical Packaging Ltd.
11.3 Packaging
FIG. 11.6 Typical off the shelf sterilization tray. (a) simple sterilization case, (b) Common device tray. Courtesy Metaphysis LLP.
The tray can be fitted with special stands to retain your device securely; this also helps theater staff to see if an item is missing. It is quite common to print a manifest of the components onto the tray in their respective locations. This all makes life for the scrub nurses, theater staff and sterilization staff easier. One of the other benefits of the tray is that is also acts as your protective inner for transportation (Fig. 11.7). Your device will probably need some transportation protection. If you use bubble wrap etc. make sure it comes from a source that is medical compliant and that you have not, inadvertently, added a risk of animal by-product contamination.
11.3.3 Packaging testing The outer box is now for transportation and storage only. It must be designed to withstand the rigors of transportation. This must also be confirmed. There are
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FIG. 11.7 Typical bespoke sterilzation tray including retainers. Courtesy Metaphysis LLP.
several standards for packaging acceptance criteria that you can follow. Remember your main aim is to get ‘your baby’ to the end user in the state in which it left you e pristine. Do not allow some delivery courier to ruin your day by rough handling. I promise you, unless you deliver something yourself you cannot guarantee the handling that you would administer. For your own sake (if only to minimize claims against damaged goods) perform simple acceptance trials such as drop tests and vibration tests. If your device is susceptible to water you should also conduct saturation tests. Table 11.3 gives some example standards. Table 11.3 Example packaging standards. Country
Standard
Description
USA
ASTM D5276 ISO 8318
Standard method for drop test of loaded containers by free fall Packaging filled, sinusoidal vibration tests using a variable frequency Packaging complete e water spray test Packaging for terminally sterilized medical devices Standard practice for commercial packaging (note for delivery to US Department of Defense)
International International International USA
ISO 2875 ISO 11607 ASTM D3592
11.3 Packaging
You may be able to conduct these tests in-house. However some are very specialized and you will have to gain access to recognized testing houses; once again most universities with an engineering department would be able to offer these services; but be sure that whoever you use is using the correct standards. Also, please do not forget that just because you have bought a standard sterilisation tray from a reputable supplier does not mean that your device can either be washed or is sterile. These facts have to be ascertained using the validation and verification tests you met earlier. The reports will be part of the Design History File and any technical documentation you will produce as a part of your CE and 510(k) submission.
11.3.4 Storage considerations Do not forget that these boxes need to be stored; if not on a shelf in your warehouse then on a shelf in a hospital. When you come to design or select your packaging ensure that it is: • • • • •
easily stored on standard shelving can be handled by one person (<25 kg) is not one-side heavy or top heavy will not degrade over the period of storage makes your device easily identifiable in a plethora of similar boxes
If your device is heavy (>25 kg or > 50 lb) you will need to consider lifting/ handling arrangements: • • • •
can it be easily handled by two people will it need lifting with specialist equipment will it need to be delivered on a pallet can the package incorporate wheels for ease of movement?
Your device may move from place to place (such as equipment on a loan or trial basis). In this case your packaging must cope with transportation, packing, unpacking and repacking. Not only does this take a toll on the packaging but it also tests your package design . after all do you want to receive a ballooning box that is crammed of your device only because you forgot to help them to repack it with some packaging instructions? The last thing to consider is where is it going to be stored? Will it be: • • • • •
dry? damp? hot? cold? dusty?
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The final resting place of an item, whilst waiting to be dispatched, is often forgotten! Also, please do not forget that some items, when packed, may need special storage instructions to avoid contamination or degradation. If this is the case make sure the packaging makes this clear, but also make sure you have the facilities to store the items yourself.
11.4 Procurement At some stage you are going to have to order your devices. You will now be in the sticky problem of e how many do I order? You must work closely with your marketing team to produce a procurement strategy. There are two main pitfalls to avoid: • •
having stock on a shelf in a warehouse having no stock at all
The former simply ties liquid assets in stock. Whilst it is nice to see wall-to-wall boxes of stock and say to yourself “look at that $1million dollars sits there”; it is better to have sold the $1million! The latter is, in fact, worse as you will not be able to fulfill orders and this may lead to the embarrassing situation of a canceled procedure. This you must avoid at all costs. Why does this affect your supply chain? If you work well with your sales department you can build a good delivery model and hence are able to work with your supply chain in a number of ways. If possible you may be able to run a Just In Time system with them. But what you must avoid is securing a supplier who can work with batch sizes of 20 per month only to start to order 50 per month. This way madness lies. As batch sizes increase so different manufacturing methods become more effective. For example for small batches you may obtain a polymer based component by machining it directly from a block: however as batch sizes increase this method of production may become costly and you may wish to change to injection molding. All of this needs planning, and you will be unable to solve this issue overnight. So the message here is plan well in advance and secure your short term, medium term and long term suppliers well in advance. If you do not your purchasing department will grow to hate you.
11.4.1 Supply chain glossary Below (Table 11.4) are some common manufacturing terms you may meet when discussing procurement with your supply chain:
11.4 Procurement
Table 11.4 Some common terms used by supply chain. Name
Description
Batch sizes
Just in Time (JIT)
Goods are delivered exactly when needed and little/no stock held on shelves. Historically a card based system that “pulls” stock as it becomes depleted The number of items in any one order A software based system to control inventory and production planning.
Large, good for regular consumables.
Literally only one (or maybe two) items are made. Each batch is different from the last A complete list of components, assemblies, and sub-assemblies for your device. The time it takes for the component to arrive after it has been ordered The flow of product is continual with equal size batches arriving at equal intervals.
Very small
KANBAN
Batch Size Materials Resource Planning (MRP) One off production Bill of Materials (BOM) Lead time Constant work in progress (ConWiP)
Any
Any Medium to large batch sizes
All
All All, but sales must be highly predictable and repetitive. This is for a product that is well established and has significant market share.
11.4.2 Costing Costing is an art. Unless you have spent your life costing the manufacture of components this is a lost cause. However most CAD packages come with an estimation algorithm built into the system. Hence it is, now, relatively easy to estimate what the manufacturing cost of a component is likely to be. Remember, the CAD system will never be able to replace the art of negotiation.
11.4.3 Manufacturing changes You may think that the manufacturing process is outside your remit d it is not. If you change a critical supplier or if that critical supplier changes a critical process,
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you should know about it. For example, say your irradiation process provider changes the isotope it uses to provide the sterilisation service d would you not want to know and assess any risks from that change? What if your supplier decides it is easier to make a component in two halves and then weld them together d should you not know this too? This is why it is SO IMPORTANT that you have an agreement with your suppliers in place so that if something does change they have to notify you so you can approve said change.
11.5 Summary In this chapter we considered the supply chain. We saw how we had to have a robust selection process culminating an approved supplier register for all of our key suppliers. We examined one of the major suppliers, sterile packagers, and we met various forms of packaging methods. Finally we examined the role of modern manufacturing technologies in a modern medical devices framework.
Further reading It is beyond the scope of this textbook to make you into a manufacturing engineer. However it is a truism that your gross margin will be dependent on the reduction of your manufacturing costs hence it will do you little harm to read further. Some suggested texts from which you can start are: Bicheno, J., Catherwood, P., 2005. Six Sigma and the Quality Toolbox. PICSIE books. Liker, J., 2004. The Toyota Way, 14 Management Principles from the World’s Greatest Manufacturer. McGraw-Hill. Vollman, B., Whybark, 2004. Manufacturing Planning and Control Systems for Supply Chain Management: The Definitive Guide for Professionals. McGraw-Hill.
Manufacturing supply chain
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11.1 Introduction It is, without doubt, that the last thing most designers concern themselves about is how a device is going to be made. We saw, right at the very start of this book, that the best way to develop a device is to have the potential manufacturers in at the start. However, one still has to find them. This chapter concerns itself with the rigors of making, maintaining, and regulating your supply chain. Notice this chapter leads to infernal confusion e manufacturer. Under EC rules as the device specifier and holder of the CE mark you are the manufacturer; as you are are in the US (specification developer). However, this does not stop you from subcontracting aspects of the manufacturing process to someone else e but you must do this properly and within a framework.
11.2 Identifying potential suppliers Once again, your quality manual should have a procedure for purchasing. The first part of this purchasing procedure always contains the identification of suppliers. You will not be able to get away with purchasing items at random, under the medical devices regulatory framework you must name suppliers for all critical components/services. In the case of the FDA it is a part of the 510(k) submission, and changing a supplier may make your 510(k) invalid; and that is somewhere you do not want to go. There are no hard and fast regulations; but I can give you some rules to follow. There is no regulation that states who you must, but common sense should suggest that you do, use a supplier who already provides components and services in your classification. Hence one would not, normally, use a company to make a class III (EC) device if they have only ever made items up to class I. Rule of manufacturing 1: Always use a supplier who has supplied items to others in your classification and that are similar in nature. Medical Device Design. https://doi.org/10.1016/B978-0-12-814962-1.00011-9 Copyright © 2020 Elsevier Ltd. All rights reserved.
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If you work with your supply chain you will find that obeying rule 1 is not difficult. All you need do is ask, most suppliers are more than happy to show off their portfolio of customers and products. Do not be afraid to ask the supplier for references e remember it is your job on the line not theirs! Identification of certification level is of paramount importance. If you are dealing with an ISO 9001 or ISO 13485 registered company then you know that their documentary trail is going to meet your needs to delegate the responsibility of quality auditing to their notified body. Rule of manufacturing 2: Always use an ISO9001 supplier as a minimum requirement.
It cannot be emphasized enough that Rule 2 will help you so much. Without this minimum certification requirement you will have to perform full audits of the company in question, yourself. This in turn means you must be a qualified external auditor (as we have met in previous chapters). Do you really want this added burden? You may if you are making a very high risk device, but for most companies audit by certification is more than adequate. Rule of manufacturing 3: For Class I measuring devices and above always look for ISO13485 certification or equivalent. Rule of manufacturing 4: For implants look for a history of implant manufacture. Rule of manufacturing 4(a): For implants you may want a quality system audit process that is “above and beyond” ISO134851
Rules 1e4 make perfect sense. They basically state that you should use someone who knows what they are doing. Do not be tempted to cut costs by dropping your own standards. The same rules can be applied to services too; e.g. Rule of manufacturing 5: For delivery of sterilization services use a recognized sterile service provider.
You may think this obvious, but some sterile packagers only provide a packaging service. Some pack and sterilize. Some will also design your pack, test it, then pack and sterilize. You MUST ensure they have the certificates and track record of the service you want. Rule of manufacturing 6: Do not forget the packaging.
1
I have known companies that have passed an ISO13485 audit with flying colors, but who fail a customer audit just a few weeks later.
11.2 Identifying potential suppliers
Rule 6 may seem simplistic, but can you imagine the situation where you have gone to all of the effort to manufacture a device that is free from animal by products only to find that someone has ordered bubble-wrap that is contaminated. Rule of manufacturing 7: Do not forget your obligation to provide the correct information.
Again, a simple rule but often overlooked. For every device you pack there will be a concurrent pack of the appropriate number of IFUs and other essential documents (labels, surgical technique, if required, etc.). Have you had them printed? Are they readily available? Are they the right ones? Where are the labels? Do not forget that the essential documentation is just as much a part of the manufacturing process as the device itself!
11.2.1 Samples Before you put any supplier on an approved suppliers list you should always obtain samples. This does not mean simply looking in a salesman’s briefcase and looking at sales specimens; it means getting them to make something from your device and then holding them to this quality when it goes into batch production. You may be asking why? The first point is that you want to ensure they can make the item to the quality you want. You will be amazed how the same drawing of a component can result in a variety of finishes; even if it is a complete drawing. The second reason is that any company can produce one excellent item; but can they produce 20 to 1000 excellent items. You can, the, use this sample as your check for the production runs. Another good reason for asking for samples is that in your quotation process you will find that suppliers have “sweet spots”. Some items they can produce with relative ease, because that is what they specialize in. These will be relatively cheap. Other items out of the “sweet spot” will cost more. And that is why Rule 1 is so important.
11.2.2 Initial audit Consider having is an initial audit just to ease your mind. This need not be a rigorous procedure but you should supply them with an audit plan (a list of things you wish to examine) and then write a brief report of this audit. You may be surprised by what you find; companies, who on paper, seem to be excellent can be a let-down when you actually get to the buildings. Do not forget to examine their own audit trail. Examples of things you should be looking for are: • • •
General cleanliness Paperwork following products Raw material quarantine procedures
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• •
Use of animal products. Tooling (potential cross-contamination)
As we have touched on earlier, the last point is of paramount importance. You MUST get a statement from the company that no animal products are used in their processes, if this is not forthcoming then you really should question their suitability as a supplier unless they are absolutely necessary.
11.2.3 Contractual arrangements Every regulatory body will expect you to have contracts detailing your subcontractors’ responsibilities.2 It is a truism that without these you will not survive an audit. The contracts need not be onerous but they must stipulate certain things: • • • • • • •
They will only make to your specification; They will not substitute materials without your written approval; They will not modify any of your part drawings; They will retain relevant documents for the prescribed period, or supply them to you for you to keep; They will supply a statement of conformity with each batch; They will not use animal by-products in any process, without your knowledge and consent; They will notify you, immediately, of any non-conformance or hazard that they become aware of that may impact on your devices.
And in addition. •
Be aware and be compliant with an unannounced audit.
In addition, of course, you will have your own performance-based criteria. Most importantly, this will need to be in the form of a contract. A simple letter to your suppliers will not do. To be complaint with the regulations, the document will need to be signed by the company acting as a supplier (to state they have received it), you will need to sign it (to state you have supplied it), and it needs to be dated. Both of you will need to keep copies!
11.2.3.1 Preparation for an unannounced audit Do not think this will not happen to you. All companies have an unannounced audit, and in the EU this can be once every three years. The unannounced audit can be at your site or at one of your critical suppliers’ sites. Because of this you need to ensure your suppliers have all of the documentary evidence an auditor will require.
2
Some of these subcontractors will be critical suppliers: their contracts/agreements would, therefore, be more stringent. However it is much better to just have one stringent agreement that you can supply as appropriate.
11.2 Identifying potential suppliers
The contract stated above is the bear minimum. They will be treated, in effect, as an extension of your company. Hence, if you state they are to keep records for you, then you better check that they do, and that they are in a form that an auditor would like to see. Do not fall into the trap of giving every suppler a copy of your technical documentation, this is NOT required. But make sure they do have up-to-date copies of drawings and specifications. If you think this is an issue why not just send a copy of what is required, i.e. a drawing, with the order. No confusion! However, it is not a bad idea to undertake an audit yourself at convenient intervals. At least, in this way, you can avoid the pitfalls of a “bad” unannounced audit e and when they are bad believe me they are bad!
11.2.4 Approved supplier register Once complete and satisfied the potential supplier becomes and approved supplier. This you need to record in an Approved Suppliers Register. The report should record the outcomes of the investigations described above, it should also contain the relevant quality certificates (which must be kept up to date). A typical register entry for a company may be as follows (Table 11.1). Obviously your register would contain all the relevant certificates and the suppliers list would be a aide-memoire for both annual supplier audits (if required) and certificate updates. You should include an audit of the register as a part of your annual internal audit process.
Table 11.1 Example layout for approved suppliers list. Part numbers
Company
Contact
Certification
Audit by
Report
Fred Smith Medical
James Machin 0485 755664 jm@ FSM.com John Brown jbrown@ JMB.com
ISO 13485 (expires Nov 2013)
Certificate Audit 14 Jan 2012
FSM1
X-101-1 100e0
ISO 9001 (Nov 2015) ISO 13485 (Nov 2015)
Certificate
JMB1
All sterile packs. Sterilisation services. Accelerated life tests for st. packs
JMB sterile packaging inc
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Note that this register has two further functions. The first is that it stops creative procurement staff purchasing items from the cheapest source only e this can play havoc with product quality. The second is that it is an information file for your design process e this file tells you “who is good at doing what” and hence who is the best person to bring in at the first stages of a design process. In small companies this is very easy, but when the company gets moderately large this type of information becomes invaluable. It is, after all, a simple contacts management system.
11.2.4.1 Critical suppliers It is, without doubt, you will be asked “who are your critical suppliers?”. This question arises due to the new EC requirement for unannounced audits (yes they can drop in to you or one of your suppliers at any time, unannounced, and charge you for the pleasure). Your suppliers must be aware of this and be fully supportive (or you will lose you certification at a stroke). However, not all of your suppliers will be critical. Some of them most definitely will, such as sterile packers and manufacturers of implantable items. In order for you to have a better idea the following selection process (Fig. 11.1).
Critical Subcontractor
Crucial Supplier
Are they producing a process or service to your specifications?
YES YES
Are they providing bespoke materials or equipment to your specification?
NO Add to list
Are the providing design or testing of the product?
YES
NO
Is their contribution a substaintial part of the product?
YES
NO
Not on list
FIG. 11.1 Discriminating a critical supplier from a generic supplier.
NO
11.3 Packaging
New supplier?
N
Procurement
Y Relevant certificates?
N
Abort
Y Audit required?
N
Order sample
Y Audit plan Conduct audit
N Satisfactory? Y Complete report, sign agreements, and file
FIG. 11.2 Example new supplier procedure.
11.2.5 Suggested procedure for supplier approval You must have a purchasing procedure to meet ISO 13485. We have met these earlier in the book, however Fig. 11.2 illustrates this section as a procedure.
11.3 Packaging Essentially packaging comes within two main criteria. There will always be some form of internal pack that protects the device and (if necessary) its sterility. The second is the outer case that is for transportation and storage. Your packaging selection protocol must encompass both aspects.
11.3.1 Sterile packaging Sterile packs tend to come in two forms, flexible wrapped and rigid blister. The flexible wrapped kind is the sort of packaging that you would see with any sterile wound dressing you would purchase from a chemist or drug store. This type of pack is reserved for relatively light objects such as adhesive dressings, small bone screws and giving sets. The blister pack is for heavier objects; ones whose shear bulk would damage the weaker wrappings of the former. For general use the sterile packaging would come single wrapped, that is there is only one seal between the device and the outside world. If, however, the device is going into a sterile environment then
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it would be double wrapped. The simple reason is that the inner pack will remain sterile and can be passed to a sterile operative. If it were single packed the packaging, itself, would be non-sterile and hence cannot be passed on to any one in the sterile field. For this reason, almost exclusively, all devices bound for the operating theater (OR) are double wrapped (Figs. 11.3 and 11.4).
FIG. 11.3 Some typical single wrapped sterile pouches. Courtesy Riverside Medical Packaging Ltd.
FIG. 11.4 A typical double wrapped sterile pouch for use in a sterile field. Courtesy Riverside Medical Packaging Ltd.
11.3 Packaging
Table 11.2 Example sterile packaging methods. Device Light/flexible Flexible wrapping
Heavy/complex shape Blister Pack Use
General/domestic Single or double wrapped
Sterile Field/OR Double wrapped
There is a range of materials from which the pouches can be made, some examples are (Table 11.2): • • • • •
63 gsm PeelPlus 1073B Tyvek 12/38 PET/PE 60 gsm Paper 12mu PET/9mu Foil/50mu Peel PE
But seek advice from a packaging specialist. The packaging will need protection from the real world, so the design of the outer carrier is of vital importance. Your package may have to travel thousands of miles before it is used and the sterile inner must get to its destination unharmed. For this reason the design of sterile packs is best left to those with the expertise and know how. Most medical devices journals have a directory of providers of this service, and of course the web is indispensable. However, follow the rules of approval described earlier. The packaging and sterilization will have to pass formal approval criteria. There are specific standards depending on your sterilization method. For example, the approval for the evaluation of devices sterilized by irradiation is controlled by ISO 11137; those by ethylene oxide ISO 11135; and ISO 17665 for steam sterilization. Your packaging must make the fact that the device is sterile patently clear (we shall see this later in labeling), it must also illustrate the sterilization method. But, in all cases the packaging will have to pass stringent tests, accelerated life tests and real time evaluations before it can be classed as a sterile packaged device. This evaluation is governed by ISO 11607. Note; your decision to be sterile or non-sterile packed should not be taken on a whim. The cost of producing a document proving your packaging and sterility regime is acceptable is high. It is not just the cost of the test, you could be scrapping up to 80 devices just to conduct the test and the cost of each item can mount up to a
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scary total. There is also the cost of maintenance; you will have to undertake regular evaluations proving your packaging is still acceptable (normally every three months) and again you may be scrapping many devices in the process. Hence your decision to go sterile must be based on good market intelligence and not just because it seems a nice thing to do. You must have better things to spend your money on.
11.3.2 Non-sterile packaging Once again it is highly likely that your device will have an inner and an outer. However your inner pack may be something quite special and could easily be a sterile pouch, as described above but just not sterilized. However take care that your non-sterile items do not look similar to sterile items e this is just too disastrous to contemplate. The benefit of this type of pouch is that all standard details can be pre-printed on the pouch itself. If your device is reusable and is to be steam sterilized then you may wish to consider the role of a sterilization case (Fig. 11.5). A sterilization case is a specifically designed tray, normally out of stainless steel or anodized aluminum, that retains your device whilst it is being washed and then steam sterilized. The whole tray, therefore, must contain your device and fit into standard washing machines and autoclaves. There are a number of specialist tray manufacturers who can design something special. Equally you can purchase one ‘off the peg’. However, as stated previously, you will have to prove that your device can be washed and sterilized in this tray . you cannot assume that is the case (Fig. 11.6).
FIG. 11.5 An example of a single wrapped non-sterile item. Courtesy Riverside Medical Packaging Ltd.
11.3 Packaging
FIG. 11.6 Typical off the shelf sterilization tray. (a) simple sterilization case, (b) Common device tray. Courtesy Metaphysis LLP.
The tray can be fitted with special stands to retain your device securely; this also helps theater staff to see if an item is missing. It is quite common to print a manifest of the components onto the tray in their respective locations. This all makes life for the scrub nurses, theater staff and sterilization staff easier. One of the other benefits of the tray is that is also acts as your protective inner for transportation (Fig. 11.7). Your device will probably need some transportation protection. If you use bubble wrap etc. make sure it comes from a source that is medical compliant and that you have not, inadvertently, added a risk of animal by-product contamination.
11.3.3 Packaging testing The outer box is now for transportation and storage only. It must be designed to withstand the rigors of transportation. This must also be confirmed. There are
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FIG. 11.7 Typical bespoke sterilzation tray including retainers. Courtesy Metaphysis LLP.
several standards for packaging acceptance criteria that you can follow. Remember your main aim is to get ‘your baby’ to the end user in the state in which it left you e pristine. Do not allow some delivery courier to ruin your day by rough handling. I promise you, unless you deliver something yourself you cannot guarantee the handling that you would administer. For your own sake (if only to minimize claims against damaged goods) perform simple acceptance trials such as drop tests and vibration tests. If your device is susceptible to water you should also conduct saturation tests. Table 11.3 gives some example standards. Table 11.3 Example packaging standards. Country
Standard
Description
USA
ASTM D5276 ISO 8318
Standard method for drop test of loaded containers by free fall Packaging filled, sinusoidal vibration tests using a variable frequency Packaging complete e water spray test Packaging for terminally sterilized medical devices Standard practice for commercial packaging (note for delivery to US Department of Defense)
International International International USA
ISO 2875 ISO 11607 ASTM D3592
11.3 Packaging
You may be able to conduct these tests in-house. However some are very specialized and you will have to gain access to recognized testing houses; once again most universities with an engineering department would be able to offer these services; but be sure that whoever you use is using the correct standards. Also, please do not forget that just because you have bought a standard sterilisation tray from a reputable supplier does not mean that your device can either be washed or is sterile. These facts have to be ascertained using the validation and verification tests you met earlier. The reports will be part of the Design History File and any technical documentation you will produce as a part of your CE and 510(k) submission.
11.3.4 Storage considerations Do not forget that these boxes need to be stored; if not on a shelf in your warehouse then on a shelf in a hospital. When you come to design or select your packaging ensure that it is: • • • • •
easily stored on standard shelving can be handled by one person (<25 kg) is not one-side heavy or top heavy will not degrade over the period of storage makes your device easily identifiable in a plethora of similar boxes
If your device is heavy (>25 kg or > 50 lb) you will need to consider lifting/ handling arrangements: • • • •
can it be easily handled by two people will it need lifting with specialist equipment will it need to be delivered on a pallet can the package incorporate wheels for ease of movement?
Your device may move from place to place (such as equipment on a loan or trial basis). In this case your packaging must cope with transportation, packing, unpacking and repacking. Not only does this take a toll on the packaging but it also tests your package design . after all do you want to receive a ballooning box that is crammed of your device only because you forgot to help them to repack it with some packaging instructions? The last thing to consider is where is it going to be stored? Will it be: • • • • •
dry? damp? hot? cold? dusty?
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The final resting place of an item, whilst waiting to be dispatched, is often forgotten! Also, please do not forget that some items, when packed, may need special storage instructions to avoid contamination or degradation. If this is the case make sure the packaging makes this clear, but also make sure you have the facilities to store the items yourself.
11.4 Procurement At some stage you are going to have to order your devices. You will now be in the sticky problem of e how many do I order? You must work closely with your marketing team to produce a procurement strategy. There are two main pitfalls to avoid: • •
having stock on a shelf in a warehouse having no stock at all
The former simply ties liquid assets in stock. Whilst it is nice to see wall-to-wall boxes of stock and say to yourself “look at that $1million dollars sits there”; it is better to have sold the $1million! The latter is, in fact, worse as you will not be able to fulfill orders and this may lead to the embarrassing situation of a canceled procedure. This you must avoid at all costs. Why does this affect your supply chain? If you work well with your sales department you can build a good delivery model and hence are able to work with your supply chain in a number of ways. If possible you may be able to run a Just In Time system with them. But what you must avoid is securing a supplier who can work with batch sizes of 20 per month only to start to order 50 per month. This way madness lies. As batch sizes increase so different manufacturing methods become more effective. For example for small batches you may obtain a polymer based component by machining it directly from a block: however as batch sizes increase this method of production may become costly and you may wish to change to injection molding. All of this needs planning, and you will be unable to solve this issue overnight. So the message here is plan well in advance and secure your short term, medium term and long term suppliers well in advance. If you do not your purchasing department will grow to hate you.
11.4.1 Supply chain glossary Below (Table 11.4) are some common manufacturing terms you may meet when discussing procurement with your supply chain:
11.4 Procurement
Table 11.4 Some common terms used by supply chain. Name
Description
Batch sizes
Just in Time (JIT)
Goods are delivered exactly when needed and little/no stock held on shelves. Historically a card based system that “pulls” stock as it becomes depleted The number of items in any one order A software based system to control inventory and production planning.
Large, good for regular consumables.
Literally only one (or maybe two) items are made. Each batch is different from the last A complete list of components, assemblies, and sub-assemblies for your device. The time it takes for the component to arrive after it has been ordered The flow of product is continual with equal size batches arriving at equal intervals.
Very small
KANBAN
Batch Size Materials Resource Planning (MRP) One off production Bill of Materials (BOM) Lead time Constant work in progress (ConWiP)
Any
Any Medium to large batch sizes
All
All All, but sales must be highly predictable and repetitive. This is for a product that is well established and has significant market share.
11.4.2 Costing Costing is an art. Unless you have spent your life costing the manufacture of components this is a lost cause. However most CAD packages come with an estimation algorithm built into the system. Hence it is, now, relatively easy to estimate what the manufacturing cost of a component is likely to be. Remember, the CAD system will never be able to replace the art of negotiation.
11.4.3 Manufacturing changes You may think that the manufacturing process is outside your remit d it is not. If you change a critical supplier or if that critical supplier changes a critical process,
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you should know about it. For example, say your irradiation process provider changes the isotope it uses to provide the sterilisation service d would you not want to know and assess any risks from that change? What if your supplier decides it is easier to make a component in two halves and then weld them together d should you not know this too? This is why it is SO IMPORTANT that you have an agreement with your suppliers in place so that if something does change they have to notify you so you can approve said change.
11.5 Summary In this chapter we considered the supply chain. We saw how we had to have a robust selection process culminating an approved supplier register for all of our key suppliers. We examined one of the major suppliers, sterile packagers, and we met various forms of packaging methods. Finally we examined the role of modern manufacturing technologies in a modern medical devices framework.
Further reading It is beyond the scope of this textbook to make you into a manufacturing engineer. However it is a truism that your gross margin will be dependent on the reduction of your manufacturing costs hence it will do you little harm to read further. Some suggested texts from which you can start are: Bicheno, J., Catherwood, P., 2005. Six Sigma and the Quality Toolbox. PICSIE books. Liker, J., 2004. The Toyota Way, 14 Management Principles from the World’s Greatest Manufacturer. McGraw-Hill. Vollman, B., Whybark, 2004. Manufacturing Planning and Control Systems for Supply Chain Management: The Definitive Guide for Professionals. McGraw-Hill.