When it comes to product design, there are many more considerations required than the way the product looks and functions. Engineers must consider electromagnetic interference, both to and from other devices; conformity to applicable standards; cost-effectiveness; and, of course, product safety. According to the United States Department of Labor, most electrical accidents are caused by unsafe equipment, installation, environment, and work practices. Workers and consumers often suffer from electric shock, exposure to arc-flash and arc-blast, and exposure to excessive light and sound energies. The last thing any product manufacturer or designer wants (or needs) is a legal battle between himself and an injured consumer—and, thankfully, most electrical injuries can be avoided. Yet, often, product designers fail to consider a product’s electrical dangers during the design process, and this is the most critical moment to consider such thoughts.
Assuming that a product is electrically safe for consumers to use is irresponsible and dangerous, and waiting until product testing to learn if your product is safe is simply a waste of time. As with EMC testing, electrical safety testing can be cumbersome if your product fails. Rather than waiting to see if your product passes electrical safety testing, engineers should consider electrical safety during the design cycle to reduce the amount of time and money spent as well as the chance of consumer injury. Here, we’ll discuss our top tips on how to design for electrical safety.
Follow Design Methodology to the T As an engineer, it is imperative that you follow design methodology to the T. Product design is a complicated and detail-oriented process that takes time and diligence. Here are some steps to always follow during the design cycle:
Risk Consideration
Design
Problem Identification
Problem Definition
Research
Limitations
Standards Evaluation
Alternative Solutions
Analysis
Decision
Specification
Communication
The very first step—risk consideration—is the most critical step when it comes to effective and safe design. During this step, engineers consider the potential safety risks their product might possess. As a good rule of thumb, consider the following question: how could a consumer potentially misuse this product? By considering these potential risks first, engineers can more efficiently design their product. Other ways to design a safer product include:
Providing maximum protection
Meeting applicable code requirements
Employing current-limiting overcurrent protective devices
Employing touch-safe components
Determining system requirements based on safety goals.
It is during the seventh step—analysis—that engineers review their design for compliance and safety. If the design is not safe, engineers are required to modify the design, according to the engineering safety hierarchy:
Modify the design to eliminate safety risks
If risks cannot be eliminated, the design must be modified so that no failures (beside risk failure) occur
Provide adequate warnings for consumer knowledge.
It is important to note that warnings should never be used as a substitute for a better, safer design.
Know your Customer This tip goes hand-in-hand with the very first step in the design methodology presented above. It is important for engineers to know their customers and to predict their needs. Consider the following questions during the first step in the design cycle:
Who will use this product? The everyday consumer or someone with technical knowledge? For instance, surgeons will know how to use a tool or device and will read the instructions very carefully. Everyday consumers often ignore instructions and are more careless with tools and devices.
Will the end-user possess knowledge regarding electrical safety or electrical systems?
Will your product, even if it does not contain an electrical system within it, be used near an electrical system? Will it interfere with an electrical system, possibly causing harm to consumers? If so, you’ll need to provide a warning.
By asking and answering these questions, you can design a much safer product.
Know the Risks It’s important to know what might happen if your product does injure a consumer. When someone is shocked by an electrical system, a current flows through their body—including their skin, muscles, and organs. This can result in erratic heartbeat, shortness of breath, tingling, and even death. Review the chart below for electrical dangers and their effects on the body:
Knowing your product’s potential dangers can help determine how to mitigate them.
No product is perfect, and electrical systems will always pose some form of risk to consumers. It is important, however, that engineers ensure they have followed all design mitigation techniques and safety regulations to the T. At Rhein Tech Labs, we can help determine whether your product is electrically safe. We can obtain safety approvals for electronic or electrical products, power supplies, Information Technology Equipment, Medical Equipment, and Audio/Video Equipment. We partner with a Nationally Recognized Testing Laboratory (NRTL) and can perform product safety testing at one location and obtain U.S., Canadian, and European approvals. If your device needs to be tested under the following standards, then request a quote from us today:
UL/IEC/EN 60950-1
UL/IEC/EN 60601-1
UL/IEC/EN 61010-1
EN60204-1
UL/IEC/EN 60335
UL/IEC/EN 60065
Sources: https://www.ecmweb.com/design/article/20890362/designing-for-electrical-safety, https://www.lanl.gov/safety/electrical/docs/arc_flash_safety.pdf