Compliance Verification Testing of

Installed ESD Protective Products

Compliance Verification Testing of

Installed ESD Protective Products

©Copyright 2011 DESCO INDUSTRIES INC.9/05

ESD TR53 Compliance Verification ESD TR53 Compliance Verification

Use ESD Association Technical Report ESD TR53-2006 Compliance Verification of ESD Protective Equipment and Materials.

Can be purchased from www.ESDA.org TR53 includes equipment, test procedures and troubleshooting tips to periodically verify the performance of ESD protective equipment and materials.

Desco.com

ESD Protected Area Clearly IdentifiedESD Protected Area Clearly Identified

“Caution signs indicating the existence of the Protected Area shall be posted and clearly visible to personnel prior to entry to the EPA [ESD Protected Area].NOTE: An EPA can consist of a single workstation, entire room or building.”

Ref: ANSI/ESD S20.20 section 8.3.

Report Visual Observations

Desco.com

Desco.com

Attention Sign

Aisle Tape

ESD Protected Area Clearly Identified

“Access to the EPA shall be limited to personnel who have completed appropriate ESD trainingUntrained individuals shall be escorted by trained personnel while in an EPA.”Ref: ANSI/ESD S20.20 section 8.3.

Report Visual Observations

Access to ESD Protected Area ControlledAccess to ESD Protected Area Controlled

Desco.com

Desco.com

Wrist Strap & Footwear Tester

SmartLogX3

Check GroundCheck Ground

“The AC equipment ground is the preferred ground connection because all electrical equipment (e.g., soldering irons,' scopes, etc.) at the workstation is already connected to this ground.” Ref: ESD Handbook ESD TR20.20 section 5.1.3

Check AC outlet properly wired with AC Outlet Analyzer

Desco.com

Desco.com

AC Outlet Analyzer and Wrist Strap Tester

Check GroundCheck Ground

Check Ground Points < 1 Ohm

Check Ground Points < 1 Ohm

•Can use ohmmeter or (as an indicator) Megohmmeter (note: if has resistor expected measurement 1 megohm +/- 20%)

•Suggest extension cord with AC Outlet Analyzer to connect to AC equipment ground and use Surface Resistance Megohmmeter without 5# Electrodes.

•Plug one lead into wrist strap ground jack and sensing lead into electrical ground

•At 10 volts, look for lowest reading if no resistor or about 1 x 10^6 ohms if there is a resistor.

• Report Rtg

Desco.com

Desco.com

Ohmmeter

Check Ground Points < 1 Ohm

No Resistor in Mat Ground CordNo Resistor in Mat Ground Cord“a direct connection from the ESD technical element to the common point ground or common connection point is acceptable and recommended.

Note: Manufacturers may add resistance to the grounding conductors for purposes other than ESD (e.g. current limiting).

… The typical added resistance in grounding conductors is 1 megohm”

Ref: Grounding ANSI/ESD S6.1 section 5.3.3

Desco.com

Rtg and Rtt ResistanceRtg and Rtt Resistance

• The most important resistance measurement is resistance to ground or Rtg. How well the material conducts charges to ground; whether material is or can be grounded

• Rtg or Resistance to groundThe resistance in ohms measured between a single electrode

placed on a surface and ground. • Rtt or Point-to-point resistance (or top to top)

The resistance in ohms measured between two electrodes placed on any surface.

Desco.com

Worksurfaces 10^6 – 10^8 OhmsUse Megohmmeter Test KitWorksurfaces 10^6 – 10^8 OhmsUse Megohmmeter Test Kit

Worksurfaces, Shelves, and Cart storage surfaces in EPA

S20.20 specifies no lower limit, however, ANSI/ESD S4.1 recommends in the manufacturing environment a resistance range of over or equal to 1 x 10^6 to less than 1 x 10^9 ohms.

Report Rtg resistance mat to equipment ground

If fails or if measures close to 1 x10^6 ohms (perhaps measuring resistor in ground cord) measure Rtt with two 5# electrodes about 10” apart measuring mat resistance itself.

Desco.com

Desco.com

Worksurfaces 10^6 – 10^8 OhmsUse Megohmmeter Test KitWorksurfaces 10^6 – 10^8 OhmsUse Megohmmeter Test Kit

Use Megohmmeter Test KitUse Megohmmeter Test Kit

• For Rtg use Surface Resistance Megohmmeter with one 5# electrode

• For Rtt use Surface Resistance Megohmmeter with two 5# electrodes• Measure at 10 volts; if over 10^5 then at 100 volts• Desco 19780 will change test voltage automatically, and has a switch to set only at 10 volts• Some other equipment use a manual switch

Desco.com

Worksurfaces 106 – 108 OhmsUse Megohmmeter Test KitWorksurfaces 106 – 108 OhmsUse Megohmmeter Test Kit

• For Rtg use Surface Resistance Megohmmeter with one 5# Electrode

• Suggest using a extension cord with AC Outlet Analyzer to connect sensing lead to AC equipment ground

• Place the one 5# electrode on mat’s center or most worn area; measure Rtg at 10 volts; if over 10^5 at 100 volts

• Measure at least one of each type or color mat and laminate.

• If fail high, measure Rtt with two 5# electrodes about 10” apart before and after cleaning (first allow to dry).

• Report Rtg (& Rtt if fail)

Desco.com

Worksurfaces Troubleshooting ESD Mat CleanerWorksurfaces Troubleshooting ESD Mat Cleaner

• Static dissipative solution cleans & restores ESD properties• Does not contain silicone which will leave a insulative film• Report observations and Rtg or Rtt before and after cleaning allowing time to dry

– Cleaners will have some alcohol as a carrier. As the alcohol evaporates, it cools the surface and thus condenses moisture on the surface. Recommended "dry time" is ~20 minutes from cleaning to retest

Desco.com

Worksurface Troubleshooting Check if Properly GroundedWorksurface Troubleshooting Check if Properly Grounded

“Grounding / Equipotential Bonding Systems shall be used to ensure that ESDS items, personnel and any other conductors (e.g., mobile equipment) are at the same electrical potential.” Ref: ANSI/ESD S20.20-2007 section 8.1

Use ohmmeter to ensure electrical continuity between components in path to ground

Desco.com

ESD Seating < 10^9 OhmsUse Megohmmeter Test KitESD Seating < 10^9 OhmsUse Megohmmeter Test Kit

• Use Surface Resistance Megohmmeter with one 5# Electrode

• Suggest extension cord with AC Outlet Analyzer to connect sensing lead to equipment ground

• Place the one 5# electrode on various seating surfaces

• Measure Rtg at 10 volts; if over 10^5 at 100 volts

• Can measure with two 5# Electrodes; one on seating and one to known good ESD Floor

• Report resistance measurements.

Desco.com

ESD Seating TroubleshootingESD Seating Troubleshooting

• If high Rtg, measure ESD Floor Rtg to determine if floor is high• If high, check if conductive casters are dirty• If high, use ohmmeter to ensure electrical continuity between components in path to ground

Note: if measuring Seating back surface ensure that you are holding insulative surface of 5# Electrode (or wear insulative gloves) otherwise could create a secondary path to ground through the person performing the test

Desco.com

Storage Shelves & Cart Shelves Electrically Connected & Grounded

Storage Shelves & Cart Shelves Electrically Connected & Grounded

• Less than 10^9 ohms Rtg; 10^6-10^8 if unprotected ESD sensitive items (ESDS) • Mats and Shelves worksurfaces to be grounded• Use Surface Resistance Megohmmeter with one 5# electrode same test as worksurface• Can measure with two 5# Electrodes to a known good ESD Floor

• If shelf material is unknown, measure Rtt with two 5# electrodes about 10” apart• Report resistance measured

Desco.com

ESD Flooring Less Than 10^9 Ohms RtgESD Flooring Less Than 10^9 Ohms Rtg

Per Floor standard ANSI/ESD S7.1 section 5.3.1.6 “Perform a minimum of five tests per contiguous floor surface material or a minimum of five tests per 5,000 square feet (464.5 m2) of floor material, whichever is greater. A minimum of three of the five tests should be conducted in those areas that are subject to wear or that have chemical or water spillage or that are visibly dirty.”

Report Rtg and Rtt if measured

Desco.com

Desco.com

ESD Floor <10^9 OhmsUse Megohmmeter Test KitESD Floor <10^9 OhmsUse Megohmmeter Test Kit

ESD Floor Less Than 10^9 Ohms RtgESD Floor Less Than 10^9 Ohms Rtg

• Use Surface Resistance Megohmmeter with one 5# Electrode

• Suggest extension cord with AC Outlet Analyzer to connect sensing lead to equipment ground

• For 3 of 5 tests, place the one 5# electrode on areas that are subject to wear or that have chemical or water spillage or that are visibly dirty. Measure Rtg at 10 VDC; if over 10^5 at 100 VDC

• If fail high, measure Rtt with two 5# electrodes about 3 feet apart before and after cleaning (first allow to dry). If tiles, place electrodes on different tiles.

• Report Rtg and Rtt if measured

Desco.com

Flooring-Footwear System Less Than 35 megohms RtgFlooring-Footwear System Less Than 35 megohms Rtg

• Use Surface Resistance Megohmmeter with one 5# Electrode

• Suggest extension cord with AC Outlet Analyzer to connect sensing lead to equipment ground

• Place the one 5# electrode on bare palm of person wearing ESD footwear standing on ESD Floor;• Measure Rtg at 10 VDC; should be < 3.5 10^7 ohms (35 megohms) resistance in series thru person – ESD Footwear – ESD Floor to ground.

• Report Rtg

Desco.com

Personnel Grounding Guideline

0

20

40

60

80

100

120

1 10 20 40

Resistance (megohms)

Bod

y V

olta

ge

Desco.com

Data used to set Resistance Limit in Combination with a Person < 35 megohms

ESD TR20.20 Figure 14 Relationship Body Voltage and Resistance to Ground

Flooring-Footwear System Charge Generation Less Than 100VFlooring-Footwear System Charge Generation Less Than 100V

• Use Charged Plate Monitor to measure electrostatic charge on a person wearing ESD Footwear on ESD Floor.

• With person connected to isolated conductive plate via a wrist strap and bulldog clip, and moving feet, report highest peak voltage

Desco.com

Desco.com

Charged Plate Analyzer

Flooring-Footwear SystemDemonstrationFlooring-Footwear SystemDemonstration

• Need both ESD flooring and footwear•To demonstrate can use Human Body Model Fixture & Ionization Test Kit • Try regular athletic shoes on ESD floor and then with ESD Footwear• Ground equipment and hold Fixture portion • Have person moving feet or walking.• Note peak voltage

Desco.com

Desco.com

Human Body Model Fixture & Ionization Test Kit

Flooring-Footwear System Charge Generation Less Than 100VFlooring-Footwear System Charge Generation Less Than 100V

Charged Plate Monitor for more accurate reading

Human Body Model Fixture & Ionization Test Kit for indication or demonstration purposes

Dance 6-step recommended in ANSI/ESD 97.2, or as people normally walk in the facility

Desco.com

ESD Protected Area Clear of Insulators

ESD Protected Area Clear of Insulators

•All nonessential insulators, such as those made of plastics and paper must be removed from the ESD workstation. Less than 2,000 volts or kept 12” from ESDS

• Visual – Are non-essential insulators present?• Measure what charge can be generated on item• Use Static Field Meter to measure ability to charge after rubbing item with hand or on your clothing.

• Report voltage; report observations of closest distance to ESD Sensitive component or assembly

Desco.com

Desco.com

Digital Field Meter

Measuring ElectroStatic Field TipsMeasuring ElectroStatic Field Tips

• Static Field Meter may have oscillating light beam to position 1” away from surface.

• Typically display ElectroStatic field in kilovolts (so 1.20 would be 1,200 volts)

• Static Field Meter to be grounded• Technician to be grounded• Measured charge on items smaller than 3"

x 3“ only an indication

Desco.com

ESD Protected Area Clear of Insulators - ResistanceESD Protected Area Clear of Insulators - Resistance

• Can measure Rtg with item between 5# electrode and ESD mat

• Use Surface Resistance Test Kit sensing lead to AC equipment ground & one 5# electrode on item on ESD mat. Note: paper absorbs moisture so may not interfere with path-to-ground, but measure with & without

• Report resistance Rtg

Desco.com

ESD Garments Compliance VerificationESD Garments Compliance Verification

• ESD Garment should be grounded via cord or ESD flooring/footwear. Can be tested while worn using a Wrist Strap or Footwear Tester < 3.5 x 10^7 ohms

• Observe that Garment is properly worn covering all

clothing with cuffs or wristband in snug contact with skin.

• Can use Surface Resistance Megohmmeter with two

5# Electrodes sleeve to sleeve Rtt

• Place Garment on insulative surface; place one 5# electrode on each sleeve or cuff. Measure Rtt at 10 volts; if over 10^5 ohms at 100 volts Desco.com

Desco.com

Garment on Insulative Surface

Testing ESD Garments Rtt Sleeve to SleeveTesting ESD Garments Rtt Sleeve to Sleeve

Essential InsulatorsNeutralized with IonizersEssential InsulatorsNeutralized with Ionizers

• “Necessary non-conductors in the environment cannot lose their electrostatic charge by attachment to ground. Ionization systems provide neutralization of charges on these necessary non-conductive items (circuit board materials and some device packages are examples of necessary non-conductors).” [ANSI/ESD S20.20-2007 Foreword]

• Test Ionizers, use Charged Plate Monitor or Ionization Test Kit

• Report Offset Voltage (Balance) & Discharge Times (both polarities)

Desco.com

Desco.com

Ionizer being Tested

Ionizers < +/-50 Offset VoltageUser Defined Discharge TimesIonizers < +/-50 Offset VoltageUser Defined Discharge Times

• Test ionizer as being used; do not clean.• Remove from the surface only those items that might block airflow.• Technician and Ionization Test Kit to be grounded. • If adjustable, zero reading, and then locate test fixture on worksurface furthest away from the ionizer where ESD sensitive products are handled.• Using Charging Unit, hold acorn nut & simultaneously press button to charge Conductive Plate.• With Ionizer operating at normal speed, use a stop watch or count time in seconds it takes to go from 1,000 volt reading to 100 volts.• Change polarity and repeat discharge time test -1,000 volts to -100 volts• Measure Offset Voltage or Balance reading after allowing sufficient time for reading to stabilize.• Record Discharge Times and Offset Voltage

Desco.com

Ionizer TroubleshootingIonizer Troubleshooting

• If poor performance, remove filter & repeat test without filter in place (passing then suggests maintenance is the problem). If still fails, remove electrical power, and clean wiping emitter pins with alcohol & re-test.

• Calibrate: adjust improving offset voltage [balance] to near zero

Desco.com

Continuous Monitors CheckedContinuous Monitors Checked

•Continuous monitoring devices should be functionally checked prior to use and periodically to ensure that they are operating as designed.

•Use Manufacturer’s Calibration or Verification Device

•Follow manufacturer’s instructions

Desco.com

Desco.com

Continuous Monitor Calibration Unit

Packaging / Material HandlingDissipative Preferred 10^4 – 10^10 ohms

Packaging / Material HandlingDissipative Preferred 10^4 – 10^10 ohms

• Can use Static Field Meter to measure ability to charge after rubbing surface. Report voltage; report observations of closest distance to ESDS

• Use Surface Resistance Megohmmeter with two 5# Electrodes

• Place Packaging on insulative surface; place 5# electrodes 10” apart if possible. Measure Rtt at 10 VDC; if over 10^5 ohms, measure Rtt at 100 VDC

• Report Voltage and/or Rtt

Desco.com

Use Shielding Bags / Containers Outside ESD Protected AreaUse Shielding Bags / Containers Outside ESD Protected Area

When not specified by [contract]… the organization shall define ESD protective packaging requirements, both inside and outside the EPA per ANSI/ESD S541.” Ref: ANSI/ESD S20.20-2007 section 8.4

Desco.com

Desco.com

In-Plant Handler

Are Re-used Bags / Containers in Good Condition?Are Re-used Bags / Containers in Good Condition?

Users should be aware that some packaging materials may be humidity dependent and may have limited shelf life. They may also lose static shielding properties by crumpling, puncturing and folding.

Report: Observations

Desco.com

ESD Packaging Properly MarkedESD Packaging Properly Marked

ESD protective packaging should be marked in accordance with ESD Protective Symbol [ANSI/ESD S541]

Desco.com

Test Per What Reference?Test Per What Reference?

• Compliance Verification of ESD Protective Equipment and Materials ESD TR53-2006

• Recommend buying a copy from www.ESDA.org at http://ESDA.org/Documents.html

Desco.com

Compliance Verification Testing of Installed ESD

Products

Compliance Verification Testing of Installed ESD

Products

Desco.com