In a previous post we talked about insulators and conductors, two important types of materials in ESD Control. We discovered why it is important to replace regular insulative items with an ESD protective version when possible. But exactly what items can and should you replace? Well, that’s what today’s post is all about. We have compiled a list of the most common workstation items, why they need replacing, and their ESD safe replacements.
Paper is everywhere in the workplace and an ESD Protected Area is no exception. The problem is it’s insulative but tends to be low charging because it is hygroscopic (absorbs moisture). Thus, the primary concern, is that ESD sensitive items get placed on top of the paper, interfering with the path-to-ground through the ESD mat. The best practice is to use dissipative paper or put regular paper in dissipative document holders or wallets.
There are many products available on the market that can assist with handling documents/paper in ESD Protected Areas:
These document wallets and holders are for use within ESD Protected Areas per IEC 61340-5-1. They are static dissipative, meaning charge is removed to ground when placed on a grounded working surface or handled by a grounded operator.
Examples of ESD safe document wallets and holders – more information
These ring binders and clipboards replace regular binders which are high charging and insulative. They come in different widths with different ring sizes and 2 or 4 rings. They are also static dissipative.
Examples of ESD safe ring binders and clipboards – more information
We all love our cup of tea or coffee in the morning, and most of us have water on standby throughout the day to stay hydrated. But do you know how much charge a foam or plastic cup generates? Well, let’s say it’s enough to damage your precious components! The answer: ESD safe drinking cups and water bottles. There aren’t too many options out there so make sure you do your research before purchasing.
ESD safe water bottles are generally dissipative.
Menda drinking cup – more information
One option for a drinking cup (for hot drinks) is the MENDA insulated drinking cup. It is low charging, and the stainless steel can be grounded when picked up by a grounded operator or placed on an ESD worksurface.
If you work with solder irons or perform various cleaning tasks, you will likely be using water or a cleaning agent. Where do you store those liquids? Plastic cups? If so, that is a BIG no-no! Those committed to their ESD Control Programmes will have switched to ESD protective bottles. ESD dispensing bottles come in all sorts of sizes, colours and with different pumps or spouts. Whatever type you need for your application, you will generally be able to find an ESD alternative.
ESD dispensing bottles are dissipative, and high-quality versions will have no migratory additives, reducing the chance for contamination from the bottle.
When an operator holds a regular brush and they wipe it on a product or assembly, tribocharging occurs. This is due to the contact and separation of the brush bristles on the product. Even if the operator is grounded, the electrostatic charge will remain on the brush fibres and/or handle. You can replace these with dissipative or conductive brushes, that will have a path to ground when held by the operator. All portions of the brush need to be conductive or dissipative, including both the handle and bristles. Select dissipative bristles if the product or assembly may be holding a charge and Charged Device Model (CDM) failures are a concern.
Probes are ideal for opening plastic cases and popping our batteries for items such as tablets, mobile phones, laptops, etc. They are also used for holding, probing, and manipulating wires and components during assembly and soldering. ESD safe versions are made of nylon, wood or stainless steel.
Examples of ESD safe probes – more information
A nylon tool, due to its hygroscopic nature, is suitable for use around ESD sensitive components when held with a bare hand for a few minutes. If used with gloves instead, nylon tools will need a coating of a topical antistatic solution. Repeat the topical treatment at least every six months. Without exposure to moisture or an antistatic treatment, Nylon is in the insulative resistance range.
Consider wooden probes as a safe material for use in ESD sensitive areas. Wood is hygroscopic and has a low propensity for charge generation under most conditions.
Stainless steel probes are conductive and will ground when held or placed on an ESD protected work surface.
ESD safe waste bins are generally conductive and are ideal in ESD Protected Areas where waste accumulates and cannot be conveniently removed except in bulk. By placing them on a grounded floor electrostatic charges are removed to ground. They do not need separate grounding when placed on a grounded surface.
Examples of waste bins and bind liners – more information
Replace standard high-charging bin liners with antistatic dissipative versions. Even at low humidity they do not become charged with static electricity.
The manufacturing of high-tech electronics requires the use of precision cutters. As electronic components have gotten smaller over time, precise cutting has become more crucial. Not only do you need to consider the type of cutter and its capabilities, you also need to consider if they are safe to use on ESD sensitive devices. The cutters should be dissipative or conductive from the handle through to the cutter itself.
As with cutters, any pliers used in the manufacture, repair, or service of electronics needs to be groundable.
Example of ESD Safe Precision Cutter – more information
“Handtools is a topic area that covers a wide range of products such as screwdrivers, lead cutters, tweezers, vacuum pick up tools. Depending on the tool design, these products can become charged during handling. If the charged part of the tool that contacts the ESD sensitive device is highly conductive an ESD event between the tool and the ESD sensitive part might occur. Tools that contact ESD sensitive devices should be tested for their ability to charge due to handling. They also need to be evaluated to determine whether or not the charge can be removed when handled by a grounded operator or placed on a grounded surface.”IEC TR 61340-5-2, 8 Handtools, 8.1
And there you have it – a list of common workbench tools and accessories that have ESD protective alternatives. Can you think of any others? Let us know in the comments!