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A Surface Resistance Meter is an instrument that measures electrical resistance of an object. It is an important tool in manufacturing, as well as static control and ESD prevention programs because it can be used to evaluate materials and classify them as conductive, dissipative and insulative.  Surface resistance meters are also commonly used to test the effectiveness of ESD control products such as auditing an ESD worksurface.

A quick internet search reveals many types with a wide range of capabilities and accessories. It can be difficult to choose which meter is right for your application.

Use our guide below to help with your decision:

1. Accuracy

2. Test Range

3. Voltage

4. Results Display

5. Temperature and Humidity

6. Electrodes

7. Memory

 

1 . Accuracy:  Verification vs Qualification

Not all resistance meters are created equal.  Meters may be designed for quick measurements to confirm specifications (verification) while

some meters are designed for more rigorous testing that requires more accurate measurements (qualification). How accurate your meter needs to be will depend on the type of testing you will be doing. Choosing a meter with higher accuracy will be a more expensive investment,  it will ensure quality measurements no matter what testing required.

Below is a table that show a variety of meters with a range of functions. “Travel” meters are excellent for quick measurements and are very portable. Lab Grade meters

Entry Level “Travel” Meter	Mid Level “Travel” Meter	Entry Level “Lab Grade” Meter	High Level “Lab Grade” Meter

 

2 . Test Range

The minimum test range required for ESD purposes is 10^3 ~ 10^12 which covers conductive, dissipative and insulative items.  Entry level meters will only have this range and will display “Less Than 10^3” for low resistance and” Greater Than 10^12” for high resistance items. More accurate resistance meters will have a larger test range.  The  Metriso 3000 has a test range from 1 Ohm ~ 1.2Tera Ohm  (1.2 x 10¹² ohm).

 

3. Voltage: Choose The Right Voltage for Your Application

Surface resistance meters use voltage to test the resistance of a material. The voltage required depends on the material you are testing and the test method. Generally for ESD testing, conductive materials (1.0 x 10⁴ ohms to <1.0 x 10⁶ ohm) are tested at 10v and materials in the dissipative range (≥1.0 x 10⁶ ohm to <1.0 x 10⁹ ohms or < 1 x 10¹¹ ohms for packaging materials) are tested at 100v. (Learn when to use 10v and 100v). Most meters will be able to test at both 10v and 100v. They may switch between the two automatically based on the material or you may have to select the voltage manually. The verification of insulative materials may call for a higher voltage, such as 500v.  There are specially designed meters for that voltage such as the Metriso 3000.

Another concept to understand with resistance meter voltage is “constant voltage”. A meter that has constant voltage does not drop significantly from the selected voltage during testing. For example, when 100 volts is selected, the meter will deliver 96 and 100 volts at the probes (standard requires ±5%). Some meters, referred to as “Open Circuit”, will drop the voltage to a much lower level when the resistance of the material measured is less to protect the meter from the returning current.  A meter with constant voltage is a much more accurate tool. The Metriso 3000 is a constant voltage meter and the output voltage at the probes is displayed during testing.

4. Result Display: How will your meter display the measurement?

Results are measured in Ohms and are sometimes displayed in powers of 10 (also known as the decade scale). The simplest readouts show values with LED lights coded with the decade scale with colors to signify conductive, dissipative, and insulative.  This readout is less accurate because the actual measurements may fall in between a decade and is rounded to the closest number. More accurate meters will display the values digitally, either in the decade scale or in Ohms.

5. Temperature and Humidity

The humidity and temperature affect the electrical properties of the material being tested. It is possible for a material to meet the requirements at high humidity, but fail at a lower humidity. Because of this, both the ESD Association and the European CECC recognize the environmental effects on test measurements and require them to be recorded.

Some resistance meters may have the capability to test temperature and humidity built in while some do not, and external devices may be required.  When in doubt, it is best to get a meter that measures temp & humidity.  If your meter does not have that capability, we supply a tool that precisely measures temperature and humidity.

6. Measuring Electrodes

All surface resistance meters contact the material to be tested with components called electrodes. Electrodes can be built into a meter (called parallel electrodes) or can be external components.  The electrodes you require with your meter depends on the tests you will perform.

Parallel Electrodes:  Two conductive rails are built into the back of the meter and are used to give fast electrical resistance measurements.  Not all meters have parallel electrodes.

External Electrodes:  A variety of external electrodes can be connected to a surface resistance meter depending on the type of test.  Here is a list of some external probes:

• 5lb disk probes – Most common probe (work surfaces, floors, shelves, carts, chairs, garments)
• Two point probe – for testing small areas (component trays, component tapes, non-planar surfaces)
• Hand held probe – testing resistance through a person
• Concentric ring probe – testing volume resistance. (Packaging materials)
• Glove Probe – Testing ESD Gloves (CAFÉ probe – Constant Area Force Electrode)
• Back Rest Probe – Testing ESD Chairs
• Clamp Probe – Testing ESD Fabrics/Jackets

7. Memory

Some meters record measurements in internal memory, making reporting very convenient. Recording measurements is a nice feature, but may not be necessary for everyone. Our Metriso 3000 can store 50,000 data points and includes software to create reports. Some mid- level resistance meters can also store data, such as the Metriso SRM200.  The amount of data points required during your testing sessions will help you determine if you need internal memory.

8. Summary

The surface resistance meter you should choose will primarily depend on the type of test required. Do you require very accurate measurements to qualification testing or just simple measurements for verification? Will you taking large amounts of tests regularly? Or just periodically?  For simple testing needs, a entry level “travel” meter such as the SRM110 will be all that is required.   For higher level testing, a mid-level Travel Meter such as the SRM200  with probe accessories or a Lab Grade Testing Kit like the Metriso B530 or 3000 should be considered.

 

If you have any questions on Surface Resistance Meters, please contact Transforming Technologies at 419-841-9552 or email info@transforming-technologies.com. You can also fill our a Form on the Website or Chat with the link on the right.

 

The ESD flooring and footwear system is an effective way to ground people that need to be on the move in a factory.   The footwear, when worn properly, is designed to drain the voltage from a person to the floor and then to ground.   Periodic testing of both the floor and the footwear is required to verify proper functioning.

Until recently, a System Resistance Test (ANSI/ESD STM97.1) was all that was needed to qualify an ESD control flooring and footwear system.  If the resistance was less than 35 megohms, it was assumed that the person’s voltage would not exceed 100 volts (the upper limit for ANSI/ESD S20.20).    However, this testing is done with the person stationary and having both feet flat on the ground.  What happens when the person starts moving and the entire foot is not making contact with the floor?

The most recent version of ANSI/ESD S20.20 now requires a Walking Voltage Test (ANSI/ESD STM97.2) be performed when qualifying flooring and footwear systems.  The test consists of measuring body voltage generate during a six step pattern used to simulate moving throughout a facility. This test will determine the actual voltage on the person while moving. Research has shown that when tested separately, ESD floors and footwear systems may pass the resistance test, but when used together, can greatly exceed the 100 volt threshold.

Determining the maximum voltage generated by people moving on the factory floor is very valuable information.  By knowing the maximum voltage generated you will know that your flooring and footwear investment is performing as designed.  You may also be pleasantly surprised to find out that the system is working quite well and you are able to handle devices with much lower Human Body Model (HBM) damage thresholds.

Equipment is available to accurately measure and record the walking voltage.  One such instrument is the WT5000.   The WT-5000 walking test kit measures and records the walking voltage while providing a graphical readout.   The instrument connects to a PC using any Windows version for easy data collection.   The WT-5000 identifies the peak voltages per the requirements in the standards.                                                

The two-in-one EFM51WT meter holds the PEAK value of the measured body voltage, as well as the LIVE static voltage measured on the operator’s body. The kit includes the EFM51 static field meter, walking test adapter plate, hand probe and conductive carrying case.  The EFM51 is a fully function field meter that in addition to the Walking Test, measures and detects electrostatic fields, surface potentials and discharge times (with optional charge plate accessory – p/n 7100.EFM51.CPS.SET.)

You have made the investment in an ESD flooring and footwear system so that people can be mobile and still protecting your products from ESD events.   Determining your actual walking voltage generated is critical to knowing that your products are being protected.

Transforming Technologies is pleased to announce we have added the BFNG10 ESD ionizing gun to our line of ionizers.

The BFNG10 is a high-performance ESD ionizing gun perfect for a wide variety of industrial applications.  The BFNG10 provides excellent balance and rapid charge decay for secure ESD workstation protection.

The BFNG10 ionizing gun combines portability, fast static decay rates, excellent balance and low compressed air consumption to efficiently remove static and contaminates in the Semiconductor, Electronic Assembly, Medical Device, Optics, Automotive and Pharmaceutical markets.

The BFNG10 works twofold: as a forceful blow off gun that quickly removes particulate from surfaces and as a neutralizer to remove the static charges responsible for the attraction of contaminants to product surfaces.

The gun body is lightweight but durable, and features a light-touch trigger, making it comfortable for extended use. A metal hanger is provided for easy mounting.

BFN series AC ionizers from Transforming Technologies create a dense and well-balanced ionization current. They are unique in their ability to deliver fast decay times with low offset voltages. Continuous balance and decay protection is assured by the reliable AC design.

Specifications:

• Designed for long-term use in an electronics production environment.
• Size: 17″x22″
• Sold in pack of five posters
• Made in the United States of America

Product information, data sheet and images can be found here:

BFNG10 Ionizing Blow Off Gun

A premium one-size-fits-all wrist strap set with a magnetic connection between the wrist strap and coil cord.

The WB3000 Series is a high quality adjustable anti static wrist strap with a 8′ or 12’ coil cord. The snaps are specially designed magnets which creates a superior electrical connection between the wrist strap and coil cords. The magnet snaps eliminate the intermittent failures and wear and tear of traditional snap and spring connections.

Specifications:

• One-size-fits-all hypoallergenic fabric wrist strap set
• Specially designed magnetic snaps provide a superior electrical connection between the wrist strap and coil cords.
• The magnet snaps eliminate the intermittent failures and wear and tear of traditional snap and spring connections.
• Dual-Wire conductor provides redundancy:  Even if one dual-wire wrist strap wire is severed, the operator has reliable path-to-ground with other wire.
• Coil Cord: 8ft or 12ft long

Application and Usage
Semiconductor, SMT Assembly, Disk Drive. The WB3000 series is recommended for use with Transforming Technologies’ Resistance Ranger Constant Monitors and are compatible with most manufacturers’ monitors*.

More Information can be found at The WB3000 Series Wrist Strap Product Page.

Cut Resistance Gloves

Cuts and lacerations are responsible for nearly 30% of lost-time work injuries in North America, the majority of which are to the hands. Wearing the correct glove is the most critical factor in proper hand protection. It’s even more important to understand cut resistant gloves and the characteristics they hold. Cut-resistant gloves come in various fabrics offering different level of cut resistance. It’s important to consider the requirements of a particular application when choosing a glove material.  Transforming Technologies specializes in anti-static gloves which improves the quality of products or solves a process issue.

What Are Cut-Resistant Gloves?

Cut Resistant Gloves can be divided into three categories based on the materials they are made from: metal mesh gloves, cut-and-sewn, and seamless knitted gloves.

Metal mesh gloves are a form of chainmail and are made of rings of stainless steel.

Cut-and-sewn gloves can be made using only a cut-resistant material or by using conventional materials with full or palm lining of cut-resistant materials. The materials are cut to shape and sewn into a glove.

Seamless knitted gloves are knitted in one piece and the cut protection is provided by high performance materials such as Para aramid (Twaron, Kevlar), Ultra High Molecular Weight Polyethylene (UHMWPE), special PVA yarns (SupraBlock) or steelfibre and fibreglass yarns. The gloves are usually coated with solid or foamed Latex, Nitrile or Polyurethane.

Which Cut Resistant Glove Is Right For Me?

Not all cut-resistant gloves are created equal and that’s a good thing, depending on the severity of the hazards that you’re facing. The best rated glove is the one that protects against the hazards you face. A worker who uses a box cutter once a day doesn’t need the same protection as someone who works in metal stamping eight hours a day.

Using a glove designed for heavy-duty cut protection for a light-duty application has a snowballing effect: If a worker has less dexterity in the glove, they won’t be able to do their job right. If they can’t do their job right, they won’t wear the glove and then compliance takes a hit. Then the risk of hand injury skyrockets!

How Are Cut-Resistant Gloves Rated:

There are two common standards used for measuring the cut-resistant properties of gloves. One used primarily in North America and the other is used in Europe and Asia.

North American Standard (ANSI/ISEA 105-2016):  The protection level is given by a number between 1 and 9, where 9 indicates the highest cut protection.All gloves are tested on a TDM1000 machine which provides uniform testing.

Transforming Technologies supplies a Cut Level 2 ESD Gloves.

1. The glove sample is placed on a conductive strip and loaded onto the TDM-100. When the metal blade touches the metal strip, the test is terminated.
2. A straight blade is loaded into the machine.
3. Weight is added to serve as force.
4. The blade moves across the fabric.
5. The blade is replaced with a new one to ensure accuracy.
6. The sample is cut five times, each with three different loads.
7. The distance traveled to cause cut through at various forces is recorded.
8. The data is used to determine the load required to cut through the sample.
9. The glove receives a rating based on the above information between A1 and A9, with A1 being the lowest and A9 being the highest level of cut protection.

European Standard (EN 388): The protection level is given by a number between 1 and 5, where 5 indicates the highest cut protection. Until 2016, the Coup Test, as described below, was the only test used under the EN 388 standard. The standard update in 2016 introduced the ISO 13997 concept, which closely relates to the North American standard test.

1. A test sample is taken from the palm of a glove.
2. A rotating circular blade moves back and forth across the test sample until a cut-through is achieved.
3. The test sample is compared to a reference material (usually cloth).
4. The reference material and the test sample are cut alternately until at least five results are achieved.
5. To help account for a loss is sharpness to the blade, the reference material is cut before and after the test sample.
6. The cut resistance is a ratio of the number of cycles needed to cut through the test sample compared with the reference material.

Can You Wash Cut-Resistant Gloves?

The short answer is yes. Laundering and dry cleaning have no significant impact on the protective properties of cut-resistant gloves. Most quality cut-resistant gloves will retain their protective properties even after ten or more washes. It is important that you follow manufacturer instructions when washing cut-resistant gloves.

Frequently Asked Questions:

Q. Do cut-resistant gloves offer good puncture-resistance?

A. No. Many cut resistant gloves are manufactured to protect hands from being slashed by sharp objects like knives/blades. However, they may provide very little or no puncture resistance from a pointed item, such as a needle.

Q. What is the difference between puncture resistance and needle or needlestick resistance?

A. Needles are sharp, beveled cutting instruments designed to pierce the skin. To stop them you need to stop the cutting action by putting something hard in front of them, such as the protective guard plates found in SuperFabric® brand materials. ASTM/EN388 test probes are rounded and tear fabric instead of cutting as it penetrates. This rounded ASTM/EN388 tip functions more to test bust strength whereas the .25G medical needle tests true needle resistance. Various testing bodies throughout the world have acknowledged this deficiency and are adapting standards to meet this. Two examples are the Canadian research organization IRRST and the ASTM F23 Standards committee, who are working together to design a standard that uses the same test procedures as tested herein.

Q. Should cut-resistant gloves be used to protect one from cuts from powered/mechanical equipment like powered saws and drills?

A. Most all manufacturers of cut-resistant gloves will not suggest the use of cut-resistant gloves for protection against powered devices. Gloves are typically tested for use with non-powered blades and sharps only.

The use of a glove with powered equipment could potentially harm an individual. If the moving blade catches the glove, it could result in a person getting pulled into moving machinery. Moving machine parts have the potential for causing severe workplace injuries, such as crushed fingers or hands, amputations, burns, or blindness. Safeguards are essential for protecting workers from these needless and preventable injuries. Any machine part, function, or process that may cause injury must be safeguarded, especially when the operation of a machine or accidental contact with it can injure the operator or others in the vicinity. These hazards must be either eliminated or controlled.

Q. What makes HexArmor products highly cut and puncture resistant?

A. HexArmor® products offer industry leading cut protection through the innovative configuration of SuperFabric® technology which provide resistance to lacerations and slashes like no other material on the market. Typical cut-resistant products are made of high performance yarns such as Kevlar®, Dyneema®, or Spectra®. While blends of these technologies protect users from straight edged cut hazards, they do not offer sufficient protection from variable hazards such as metal burrs, wires, or slivers.

ESD jackets, also commonly known as ESD smocks, ESD lab coats or ESD garments, offer protection from electrostatic fields generated by clothing on the user’s body.  ESD jackets are worn where ever static damage is a concern.  ESD jackets differ from common work garments because they are made with a grid of conductive fibers throughout. The grid creates a “Faraday Cage” effect around the body of the operator that shields charges generated from the operators clothing from damaging ESD sensitive devices. The conductive fibers also lowers the static charge generation of the jacket(also refereed as tribocharging) to a safe level.

ESD Jackets as part of a complete Quality Control Program.

ESD jackets are the most visible sign of ESD protection and any facility that mandates ESD garments demonstrates a commitment ESD protection. ESD jackets are a recommended addition to a program that already includes typical grounding measures, such as wrist straps and heel grounders.  This is because of the potential hazard of the operator’s clothing.  The ESD TR20.20-2008 states: “While a person may be grounded using a wrist strap or other grounding methods, that does not mean that insulative clothing fabrics can dissipate a charge to that person’s skin and then to ground. Personnel clothing usually is electrically separate or isolated from the body.”

How To Choose an ESD Jacket?

A quick search online reveals numerous options for ESD jackets. We have summarized the main considerations when choosing ESD jackets:

ESD Garments come in many shapes and sizes.  Typical distinctions are:

• Fabric Composition
• ESD Properties
• Collar Options
• Sleeve Terminations
• Length
• Color 
• Embroidery

The jackets you choose will most likely depend on style preference but the ESD properties should be the first priority to ensure the jackets will protect against ESD as intended.

ESD Properties
There are three classifications of ESD jackets per ANSI / ESD S20.20: an ESD Garment is defined as either:

• Level 1: Static Control Garment (surface resistivity of < 1 x 10^11 ohms resistance);
• Level 2: Groundable Static Control Garment (surface resistivity of < 1 x 10^9 ohms resistance); or
• Level 3: Groundable Static Control Garment System (surface resistivity of < 3.5 x 10^7 ohms resistance).

ESD jackets are classified by ESD properties (how conductive they are), with level 1 being the lowest and level 3 is highest. Level 1 jackets are typically the lowest cost but because the ESD properties are low they may wear out faster and need to be replaced more often. Level 3 jackets are conductive enough that the fabric can be used as part of the ground path for wrist straps which allows for safe, hands-free grounding. Level 2 is in the middle.

How to Test ESD Properties

There are several ways to test an ESD jacket but for general purposes, a sleeve-to-sleeve measurement is the most important.  This test is used to confirm electrical continuity across garment panels and sleeve components.  At minimum, an ESD jacket must be dissipative (surface resistivity of < 1 x 10^11 ohms resistance).  This test is performed with a Surface Resistance Meter.  The ESD properties should be included in the data sheet for the ESD jacket from the manufacturer. It is always recommended to regularly test your ESD jackets because wear and tear and laundering will effect the ESD properties over time.

Fabric Composition

Fabrics composition will vary by the manufacture but are typically made with a combination of carbon with polyester fabric or a cotton polyester blend.  Commonly, the fabrics are described with a percentage. For example, 88% polyester and 12% carbon.  Your choice of fabric will be determined by operator comfort and ESD performance.  You may choose a lightweight polyester for warmer climates or a cotton polyester blend for cooler climates. 

The amount of carbon in the jacket is important to note because this is the element that makes the jacket “ESD safe”.  The more carbon, the better the anti-static performance.  Lower cost ESD jackets are available with a carbon content of less than 5%, but they may not perform well or last as long as jackets with higher carbon content.

Collar Options
Collar options typically include Lapel, V-Neck or Military style.  The type of collar you choose will be based on user comfort and sensitivity of the application.  The various collars allow more or less clothing to be exposed to your environment. V-Neck collars are the most open and may be cooler to wear. Military Collars covers the most clothing, but may more uncomfortable to wear.  Lapel collars are in between the two and are the most commonly used collar.

Sleeve Terminations
ESD jackets have either a Snap Cuff or an ESD Knit Cuff. The snap cuff includes three snap that adjusts for a proper fit and are typically cheaper. The three snap cuff is ideal when you already have wrist-straps, or in cases when wearers find the cuffs a little too snug. A wrist strap can be snapped to the garment sleeve and cord is attached at the hip pocket to ground both the person and the jacket.

An ESD Knit Cuff is very similar to the cuff on the end of a sweatshirt and allows for hands free grounding. ESD Knit cuffs form a contact path around both of the wearer’s wrists. The garment and wearer can then both be grounded by attaching a ground cord to the 4mm stainless steel snaps on the hip pocket.

Short sleeve jackets are also available from some manufacturers.

Length
ESD jackets come in three lengths: waist length, 3/4ths and full length.  The length you choose depends on the sensitivity of the application and the comfort of the wearer.  Waist length jackets leaves the most clothing exposed but may be cooler. Full length jackets cover the most clothing by going down to about the knees and are sometimes referred to as lab coats.  3/4ths length jackets come down to mid-thigh and are between the waist length and full length.

Colors
ESD Jackets come in many colors, with blue the most common. The color has nothing to do with performance and is only preference by the company using them. Many companies will color code their employees with their ESD jackets. For example, employees may wear blue, management wears black and visitors wear white.  High-Visibility jackets are available for safety reasons. Color options vary by manufacturer, and by fabric. Jackets may also be died to match company colors but will have a high minimum order quantity.  

Embroidery of ESD jackets

Many companies choose to embroidery their company logo or employee name onto their ESD jackets.  Sublimations, screen printing and patches are also ways to add logos or names.

Conclusion

ESD Jackets are an important part of an ESD program. There are many styles to choose from, but ESD properties should be the most important factor in choosing an ESD jacket. After you ensure your jacket will protect your application, you have your choice of fabrics, collars, sleeves, and colors.

View Transforming Technologies’ line of ESD Jackets.

Need help choosing an ESD jacket? Call Transforming Technologies at 419-841-9552. Or email info@transforming-technologies.com or fill out our contact form below.

Transforming Technologies, a supplier of a wide range of ESD products, has added the StaticCare^TMGL2500 Series ESD Cut Gloves to their line of ESD Apparel.

Transforming Technologies, a supplier of a wide range of critically important ionization, matting, grounding, test equipment and ESD apparel for protecting static sensitive electronics, has added the Staticare™ GL2500 Series ESD Cut Gloves to their line of high-quality ESD Apparel. The Staticare™ GL2500 Series ESD Cut Gloves combine powerful cut resistance, comfort, and uniform ESD protection into one superior performing glove. The gloves are certified ANSI Cut Level 2 while maintaining softness, flexibility, and comfort.

ESD Protection
The Staticare™ GL2500 series gloves provide superior ESD protection because conductive carbon threads are combined with the cut resistant fibers to provide uniform static decay rates. Typical surface resistance is less than 10^7 ohms per ANSI/ESD SP15.1

Cut Protection
The Staticare™  ESD Cut Gloves are constructed with 18-gauge Ultra High Molecular Weight Polyethylene (UHMWPE) thread which provides great cut protection, outstanding abrasion and tear resistance. The gloves are rated ANSI Cut Level 2, which offers a basic level protection against cuts or punctures.

About Transforming Technologies
Since 1998, Transforming Technologies has provided a wide range of unique and outstanding products to detect, protect, eliminate and monitor electrostatic charges. Transforming Technologies provides comprehensive knowledge of electrostatic issues, effective solution-oriented products, and outstanding, friendly service. We specialize in:

• Grounding Products
• Cleanroom Supplies
• ESD Apparel
• Ionizers
• ESD Matting
• Test & Monitoring Equipment

Headquartered in Toledo, OH, USA, Transforming Technologies offers a wide range of critically important ESD products for protecting static sensitive electronics. Our products are key tools used by industries to assure an effective static control program.

Contact:
Sales and Marketing
Transforming Technologies
419-841-9552
sales@transforming-technologies.com
www. transforming-technologies.com

The conveyor belt is an indispensable part of the automatic transportation equipment. But the conveyor belt can be a major generator static electricity that can cause numerous problems, from static shocks to employees to catastrophic damage to components. The cause of static is friction, and on belt conveyors, the belt surface is continually rubbing the pulley surface, generating static electricity. As the conveyor continues to operate, the static charge will continue to accumulate and increase unless it is bled off (or discharged) in some manner.  Conveyor and assembly trays can also create a static charge and shock employees.

Anti-static conveyor equipment exists, so when choosing the conveyor belt, pay special attention to whether the belt has anti-static characteristics.  A surface resistance meter can be used to measure the anti-static properties of a conveyor belt. But if your equipment is not anti-static, then you must eliminate static in other ways.  The first step in eliminating static is to measure it.  If you can feel the static charge or receive shocks, then the charge is already way to high and needs to be addressed.  Human feel static at 2000 volts, but components can be damaged with as little as 100 volts.  A static field meter can be used to measure the static charge on your conveyor.

Drag chains can be a do-it-yourself solution to drain a charge, but they are not always practical or effective enough.  Anti-static ionizers are the most effective method of eliminating static on conveyors. Ionizers blow specialized air that eliminates static charges.  They are designed to be mounted overhead, or in targeted areas and can be effective without interfering with the movement of the conveyor or components. Ion bars are excellent for conveyors because they can cover wide areas with a relatively small footprint. A three fan overhead ionizer is also an effective ionizer for conveyors. If the target area for ionization is small, ionizing nozzles can be very effective.  They provide a targeted stream of ionized air that can even be activated automatically with a photoelectric eye.

Placement:
This will vary by application.  Mount ionizers at friction points in your process and the locations of the biggest static issue. Mount the ionizer as close to the problem area as possible, but not too close that the ionizer does not have enough time to do its job.  If your employees are getting shocked, you will want to install the ionizer just prior to the employee exposure.

Conclusion:

Conveyors generate static due to friction, which can cause numerous problems. Anti-static ionizers are a very effective tool to remove the static charge.

View all of Transforming Technologies Anti-Static ESD Ionizers here.