Designing Packaging for Sterilization
Packaging is one of the last stages of the design and development process for a terminally sterilized medical device, despite it being at the end, it is a critical aspect of the design. Packaging keeps the product sterile and safe prior to use. A terminally sterilized medical device is a product that has been exposed to a sterilization process in its sterile barrier system to reduce disease transmission by killing viable microorganisms, they must follow ISO 11607: 2019 Packaging for Terminally Sterilized Medical Devices.
The packaging is what keeps the product sterile and functional after the sterilization process, shipping, transport and storage. Packaging is required to go through several different validation studies to ensure that the packaging system works properly including a shelf-life study and a shipping/distribution testing. This article will be focused on designing packaging for sterilization to ensure you are optimizing the sterilization process and the product packaging.
The medical device packaging typically includes several layers of protection for a product. The product is put on a tray or backer card then the lid is sealed or is put into a pouch and sealed shut. The pouch, depending on the type of sterilization, may have breathable material to allow for proper sterilization. This pouch or lid is what keep the product sealed and sterile after the sterilization process.
Once there is a sterile barrier system such as a pouch, product is typically placed in a carton. Then a certain number of cartons is placed in a shipping box. This entire design is considered the packaging system. Labels will need to be on the pouch, carton and shipping box.
Designing the packaging should start earlier than you may think. There are many different factors that play into the design of the packaging including sterilization, shipping and the end user. During the entire design process, keeping the end goal in sight is very important. The packaging should be safe, cost-effective, and readily available. Packaging materials should never be the thing holding up market launches or product shipment.
DESIGN FOR STERILIZATION
There are two main aspects to consider when designing for sterilization 1) determining what type of sterilization is required and 2) what are the product volumes at market launch and beyond.
There are four main types of sterilization: Ethylene Oxide, Gamma, E-Beam and Steam. Ethylene Oxide is a great method known for its low temperature and compatibility with all plastics and metals. Gamma and E-Beam both use different irradiation methods and is compatible with most materials but can cause discoloration and brittleness in some materials. Steam is used mostly in a just-in-time manner at the hospital, it works well with metals but no other materials due to the high temperatures and humidity. Currently, Ethylene Oxide makes up more than 50% of the industrial sterilization in the US because of its compatible with nearly all materials and efficacy.
The amount of product that will need to be sterilized at a time will affect the decision of what type of sterilization. Product is regularly sterilized in pallets; however, there are some growing options for smaller volumes. Gamma and E-beam require large amounts of product, think pallets, Ethylene Oxide varies from small chambers of 8 cubic feet to truck loads at a time. Steam sterilization is typically low volumes and completed at the hospital. Ethylene Oxide can be the most flexible option as the chamber sizes vary the most. Small chamber Ethylene Oxide can be a great choice for high value products, modest volumes, small sized products and R&D work. Starting with a company like Boulder Sterilization which has smaller chambers can give you an advantage with quick turn around and less up-front costs.
Once a sterilization method has been chosen, the type and size of the packaging can be chosen.
Depending on the type of sterilization that is chosen for the product, the packaging will need to be different. For example, Ethylene Oxide requires a breathable material such as Tyvek to be a part of the packaging to allow for easy entrance and exit of the gas into the package and product. Gamma and E-Beam require slightly different packaging configurations. Steam requires a similar pouch to Ethylene Oxide. All pouches or lids need to fully seal the product in the package so no molds, yeasts, viruses or bacteria can find their way onto the product.
The size of the packaging can affect the cost of sterilization significantly. Contract sterilizers deal with set chamber constraints. Designing the packaging to these constraints can optimize the amount of product you can fit into one sterilization run and reduce production costs down the road. I recommend always reaching out to sterilization vendors first to understand their chamber sizes while designing the packaging. For example, if you have 2 inches of extra space on the edge of a pallet that is unused space that adds up in cost. For smaller chambers, this is especially important since the amount that can fit into the camber could change in an order of magnitude. Here at Boulder Sterilization, we try to emphasize the best practice of design the packaging with space utilization in mind. If your packaging can be smaller, the more product you can fit in the sterilization chamber reducing costs.
Designing the packaging with sterilization in mind will save you time and money in the end by ensuring the packaging will keep the product sterile and optimizing the space available. We have had clients in the past who chose to go with E-Beam, then found out that their product will not work with E-Beam, had to redo all the packaging and switch to Ethylene Oxide.
OTHER DESIGN ASPECTS
There are certainly other aspects to consider when designing packaging.
The packaging should keep the product from damage during shipping and transportation, there are plenty of questions to consider. What will the typical mode of transportation be? Does it need to fit in a custom shipping box or would a Fedex box work just as well? Would you ever want to ship in different configurations? In addition to shipping, understanding the typical storage conditions is also important. Will the product ever see extreme temperature or humidity in storage? Do you need to constrain these conditions? How long does the product need to be able to sit on the shelf?
Not only designing for sterilization and shipping/storage is important but also, designing for the end user. Who will be using the product? Will they be concerned more about the function or look of the packaging? Is it going to be sitting on a hospital shelf, what size if the shelf? Does the end use have access to recycling or large trash cans for additional packaging materials? Does it need to be double pouched? These are all additional considerations that should be thought of during the packaging design and just as important as the product itself. If an end user can’t open the package in an efficient manner, their satisfaction will decline.
It can be difficult to weigh and rank all the aspects that go into the packaging for a sterile device. Making sure to design the packaging upfront is any easy way to save time and money. By figuring out the sterilization needs and vendor concurrently with the packaging design, along with thinking of the shipping, storage and end user can create a great packaging system that will work with a stake holders.
Designing Packaging for Sterilization
- What is packaging for industrial terminally sterilized devices?
- Why is this important
- Packaging Details
- What does the packaging look like
- Start with the packaging design early
- Design with end goal in mind: safe, cost effective, packaging to keep the product ready for use
- Important Packaging Design Aspects:
- Design For Sterilization
- Determine what type of sterilization is required
- What volume of sterilization – how important is size of box
- Design for Shipping, Transportation and Storage
- Number of years needed for shelf life
- International shipping?
- Determine where the finished good will be stored
- Design for End Use
- How will the end user interact with the product? Double pouched required?
- Risk analysis of the product
- Design for all – balance the cost and benefits of more storage
- Design For Sterilization
Peggy Fasano, former Chief Operating Officer, Boulder iQ