Sparks. Explosions. Damage to equipment and electronics. Device malfunctions.
There are a number of safety threats present in any manufacturing or industrial environment, but you might be surprised to learn that the aforementioned hazards are all associated with the presence of static electricity. Static electricity isn't just a tolerated nuisance, but it can be a matter of life or death - and that's why it's so important to manage it properly.
This post covers what static electricity is, why it's so dangerous, and how to manage it. Read on to learn more about static electricity control measures for manufacturers:
Static Electricity 101: What to Know
So, what is static electricity? Simply put, it consists of an imbalance between negatively and positively charged objects. Also described as a "non-neutral electric charge," it's something that everyone has experienced at some point during their lifetime. A great example is a balloon sticking to the ceiling. Or someone's hair sticking up in a dry room. During the winter months, you might even feel a static shock after you walk across a carpeted room and touch something metal. Lightning is also an example of static electricity.
When two objects touch, they exchange electrons with each other. If these electrons aren't grounded, they're likely to build a charge due to the imbalance and lead to an electrostatic discharge, or ESD. This imbalance can be corrected to prevent the charge, which becomes important in manufacturing settings.
Industries Troubled by Static Electricity
In most situations around the home or office, static electricity is harmless. But in industrial environments, any buildup of static can be very dangerous. If charges build to unsafe levels, it can lead to a spark. And depending on the industry, this spark could lead to property damage and cause bodily harm. Beyond this, the presence of static can also slow productivity, lead to product defects and harm a firm's reputation with consumers.
Some of the industries that are regularly challenged by the presence of static electricity and must have the right plan in place to mitigate such buildup include:
- Electronics manufacturing
- Plastics manufacturing
- Converting and printing (packaging)
- Medical device manufacturing
- Cleanrooms and laboratories
How Static Electricity Impacts Products, Processes, Machinery and More
When we experience a static shock in our homes, it lasts for only a second and is nothing more than a minor inconvenience. But in the industrial setting, any spark created by a static charge can be extremely dangerous.
Think of this spark in an industrial environment the same way you'd think of one that was caused by two objects connected to a wire. As you might imagine, there's a serious risk of fire or explosion around flammable objects or chemicals. It's estimated that a single spark can generate up to 3,000 volts of electricity, making the presence of static a serious threat.
Even if static doesn't result in an explosion or fire, it can lead to costly product damage. Latent damage is when static destroys or damages electronics or semiconductor applications within a product. And while any issues related to a static shock may not come to fruition for several weeks, latent damage can still shorten the lifespan of a product.
Another example of how static electricity can impact a manufacturing environment is via dirt and dust collection. Going back to the balloon sticking to the ceiling example, when a product or device becomes ionized, it can also bring other things to its surface. If dirt and debris are allowed to contaminate products or processes, it could lead to contamination, defects, health hazards, and poor overall quality. This is why ESD control for manufacturers is critical.
Regulating Static Electricity
To facilitate a safe manufacturing environment, there are some well-known regulations as it pertains to controlling static electricity in various environments. Here's an overview of some of the most well-known regulations:
- U.S. Code of Federal Regulations: 29 CFR Part 1910 Occupational Safety and Health Standards states that ignition sources present in flammable atmospheres must be mitigated and controlled. These ignition sources include static electricity.
- Canada's Occupational Safety and Health Regulations: Section 10.12 states that if substances are flammable and static electricity is an ignition source, employers must implement standards according to the U.S. National Fire Production Association's recommended practice on static electricity.
- ATEX Directive 2014/34/EU: This European standard states that electrostatic charges capable of resulting in dangerous discharges must be prevented by appropriate measures.
How to Prevent Static Discharge
How do you prevent static discharge in industrial environments? There are a variety of ways, from disposable antistatic clothing to ventilation and humidity control. Many industrial environments will utilize one or more of the following methods to control static electricity in their environments. Here's an overview of the many ways manufacturers can stay in compliance with their governing regulations and eliminate any safety or product defect risk due to the presence of static:
The addition of inert gas in or around the areas where sparks are likely to occur can help avoid sparks. Common examples of inert gases used in manufacturing include purified argon gas and helium.
Humidification and Ventilation
Static tends to build more in dry environments, as any moisture in the air helps disperse the charge on an object. Hence, humidity control can help to control static buildup. It's suggested that humidity remains above 60 percent to do so. This can be done with humidifiers. Ventilation can also help control humidity and temperature in an environment.
Antistatic Treatments and Charge Neutralization
There are a variety of antistatic treatments and charge neutralization methods and technologies that may be considered for controlling static based on the industry and environment. For example, an anti-static bar, or “ionizing bar”, creates an electric field that transforms air molecules around the bar into positive and negative ions. This is done using high voltage contained in emitter tips. All charged materials in the vicinity attract opposing ions, until they are electrically neutralized.
There are also antistatic agents. An antistatic agent is a compound used for treating materials or their surfaces to reduce or eliminate the buildup of static electricity. These agents are often available in the form of a liquid that is sprayed on surfaces to neutralize any static buildup. There are also anti-static guns that emit positive and negative charges to neutralize static on a surface.
Control of Static Charge Generation
Controlling static charge generation by controlling flow rates and allowing for sufficient relaxation and residence time is a means of controlling static generation.
Bonding and Grounding
Using bonding and grounding clips or other devices can help create a good metal-to-metal connection to prevent electrostatic charge dispersal. Bonding involves connecting one more objects together, while grounding consists of connecting an object to the ground. Grounding is often considered the safest way to dissipate any electrical charge.
Wearing ESD-Safe Clothing
Wearing the right personal protective equipment (PPE) - from antistatic clothing to disposable antistatic workwear - is another method to prevent the buildup of static in industrial environments. Such clothing will help prevent static buildup and discharge and should be utilized to complement many of the other mitigation strategies included in this post.
International Enviroguard offers anti-static clothing for a variety of industries including healthcare, pharmaceuticals, cleanrooms, controlled environments, petrochemicals, oil and gas, and more. Anti-static PPE is certified to EN 1149-5 as this standard covers the performance requirements of the garments. The EN 1149-5 standard describes the requirements for electrostatic properties for safety apparel that is used in areas with a hazard of sudden electrostatic discharge or a risk of explosion.
All products listed below meet the requirements for ESD safety in accordance with all referenced specifications for both static decay and surface resistivity. Garments are therefore considered safe for use in ESD-sensitive environments and applications.
Our products that are anti-static include:
- ChemSplash®1: Chemical, acid, and toxic particulate coveralls and accessories
- ChemSplash® 2: Heavy-duty chemical, caustic, acid, and toxic particulate suits
- MicroGuard MP®: Microporous coveralls and accessories
- MicroGuard CE®: Clean-processed, microporous coveralls and accessories
- PyroGuard FR®: Flame-resistant (FR) coveralls
- PyroGuard CRFR™: Flame-resistant and chemical resistant coveralls and accessories
- Soft Scrubs™: Three-layer SMS scrub tops and pants
Other ESD Control Methods
Additional strategies for controlling static electricity include:
- Modifying the volume or surface resistivity of insulating materials with antistatic additives like carbon fibers
- Ionizing air near insulating materials
- Treating carpets with a topical anti-static spray or using anti-static mats
Don't let static ruin products or processes in your manufacturing environment. Take the time to understand which parts of your operations are particularly at risk and put in place the right control strategies. Failure to do so could be hazardous to your people and to your business.