Ensuring compliance to ESD requirements and standards presents challenges, especially in light of recent ESD Association changes. Depending on your workplace or environment, improper ESD control can cause fires or explosions resulting in costly damage and injuries. For these reasons, maintaining compliance, and ensuring your program’s efficacy, requires due diligence, including the careful selection of all appropriate instrumentation and other equipment.
Selecting the right equipment for the job at hand is paramount. Desco’s ESD control products are designed to help you maintain compliance with your organization’s ESD program, the basic tenets of which likely include the following:
- All conductors of electricity should be grounded to ensure an equipotential balance of electrical charge at all times in protected areas.
- Ionized-air sources should be provided to neutralize electrostatic charge on the necessary nonconductors in protected areas.
- Appropriate static control packaging or containment for protection of sensitive items should be used when the items are removed from protected areas.
ESD control products from SCS, on the other hand, are primarily comprised of testing and measurement equipment, so you can verify your program is working properly. When used in conjunction, Desco and SCS brand products help to create fail-safe methodologies for an efficient and safe ESD program in any environment.
So, you designed your ESD workstation. Now what? Now you need to evaluate your ESD work surface. Your company probably has a laundry list of items that must be tested along with a testing schedule that meets industry standards. When it comes to the work surface, there are three primary measures that should be taken: Resistance to Ground (RTG), Resistance to Groundable Point (RTGP) and Resistance Point to Point or Resistance Top to Top (RTT). How often you take these measurements will vary based on internal requirements and testing history.
Resistance to Ground
This is the main measurement for general auditing purposes. Place a 5-pound electrode, connected to the positive terminal of the resistance meter, onto the most heavily used area of the work surface. The negative lead is connected to electrical ground. This measurement ensures the mat is connected to AC equipment ground. Test at 10 volts, and if the measurement exceeds 1.0 x 106 ohms, switch to 100 volts.
Resistance to Groundable Point
This measurement is taken much like the RTG measurement except the negative lead is attached to the grounding point of the work surface. Perform the test using 100 volts when the expected resistance is greater than 1.0 x 106 ohms. If the measurement exceeds your limits, there may be a problem with the work surface.
Resistance Point to Point
Take this measurement by placing two 5-pound electrodes 10 inches apart on the work surface. The testing is performed using 100 volts when the expected resistance is greater than 1.0 x 106 ohms. If the reading exceeds your limits, the work surface probably needs to be replaced.
As you evaluate your ESD work surface, consider incorporating these tests into your audit for good measure.
How do you manage static? First and foremost your workstation must limit electrostatic voltages and ESD (electrostatic discharge) or it’s not doing its job. Begin by grounding all work surfaces, people and equipment to the same electrical ground point or “common point ground.”
You can take a variety of precautions to limit risk to sensitive devices, but depending on your situation, they may not all be necessary. For example, what about your personnel? Are they stationary or mobile? What’s mandatory or suggested for one may be optional for the other.
As you design your unique ESD workstation, you’ll need to weigh the relevant factors; however, the following list of equipment is common and generally standard for basic ESD protection:
- Table Mat
- Floor Mat and Ground Cord
- Wrist Band and Coil Cord Set
- Heel Grounders
- Constant Monitors
- ESD Jackets
- ESD Equipment Testers
- Air Ionizers
How does your ESD protection program measure up? If it’s getting a mediocre or failing grade, don’t worry; you don’t have to go back to school. The ESD Association can help you implement standards into your day-to-day operations.
When do you measure your wrist strap’s resistance? At the beginning of your shift? What about re-testing after breaks or before you’re allowed to enter the ESD Protected Area (EPA)?
Your company probably has established protocols in place for wrist strap testing, but at some point while handling ESD sensitive devices, your wrist strap system will fail.
And, when this happens it’s always hard to determine exactly when the failure took place and how much product is at risk. If you’re resistant to continuous monitoring systems, here are a few reasons why you should consider integrating them into your daily operations:
- When there’s a problem, constant monitors notify operators immediately, so no product is handled until the problem is resolved.
- They eliminate the possibility of a functional wrist strap but a defective ground attachment because the systems monitor the wrist straps on the premises.
- You won’t need to record and store test results anymore.
- Some systems also monitor the connection from the work surface to ground.
You are also likely to see long-term cost savings from constant monitoring due to lower rejection rates of devices. So, all in all, today’s wrist strap monitoring doesn’t have to be a constant struggle.
It’s always better when you make it from scratch. It’s always exactly like you want it because you create it. The same goes for scratch-made Conductive Blow Molded Cases from CCI.
CCIs tailor-made approach to ESD-safe packaging means your expensive circuit boards are protected to the nth degree. Custom thermoformed and foam interiors cushion components to exacting specifications.
These cases stack up to high-pressure situations, so you’ll never sweat over their stability. They’re built to withstand immense physical pressure. Double wall construction ensures durability over and over again, and a secure closure cinches the case!
Looking for more custom, ESD-safe solutions for shipping, handling or storage processes? Look no further than All-Spec. We’ve partnered with CCI to breathe life into your ideas. So, go ahead and dig into your scratch-made staples—and come back for seconds.