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ESD Protection - Hair

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There is a battle brewing over a new policy with long hair a... - Aug 29, 2012 by hoss67  

#67150

ESD Protection - Hair | 29 August, 2012

There is a battle brewing over a new policy with long hair and ESD protection in our facility. I'm not finding a lot of evidence to support the position. Any info you all can provide on the subject would be appreciated. Studies on the subject supporting the risk would be preferred.

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#67151

ESD Protection - Hair | 29 August, 2012

You should be more concerned about hair color and ESD not the length.

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#67152

ESD Protection - Hair | 29 August, 2012

If hair were not charged (and discharged) through the body, please explain the reason for hair standing on end when one places ones hand on an ES source.

What is your control level?

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#67153

ESD Protection - Hair | 29 August, 2012

I would worry more about a hair falling out and getting into the process. Longer hairs effect more parts/area.

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#67157

ESD Protection - Hair | 30 August, 2012

Often, people cause ESD damage. • Your body easily picks up charge (electrons) • Your skin, hair and body can store relatively large amounts of static charge. • You can transfer (discharge) this electrical charge to components or assemblies - causing ESD damage. All of these really should not be present at an ESD-safe workstation. However, if they MUST be there, then it is necessary that they be kept a minimum of 12 inches away from ESD sensitive devices.

From "ESD ElectroStatic Discharge Tutorial" ... ESD and the tribo-electric series: The size of the charge which is generated is determined by a variety of different factors. One is obviously the conductivity of the two materials and also whether the charge between them can leak away. However one of the major influences is the materials themselves and their position of the two materials in what is called the tribo-electric series. The position of the two materials which are in rubbing against one another in this series governs the size of the charge and the relative polarities. The further apart they are in the series, then the greater the charge. The material that is higher up the series will receive the positive charge, whereas the one lower in the series will receive the negative charge. Materials such as human hair, skin, and other natural fibres are higher up the series and tend to receive positive charges, whereas man made fibres together with materials like polythene, PVC and even silicon are towards the negative end. This means that when combing hair with a man made plastic comb, the hair will receive a positive charge and the comb will become negative.

positive charge

skin hair wool silk paper cotton wood rubber rayon polyester polythene pvc teflon

negative charge

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#67160

ESD Protection - Hair | 30 August, 2012

This may have been asked, but what ESD protection does your facility already have? With proper techniques and equipment, this should be a non-issue. As long as folks aren't using the pcb's to comb through their hair, you don't have to worry about it. It sounds like someone in management has a quick trigger finger before acquiring all the facts. Use ESD dissipative paint for your shop floor, properly grounded. But at the very least, everyone should be wearing ground wrist straps while a the work station with ESD mats on top. Heal straps can be used if you have conductive paint. Also, check your ground straps every day with a ground strap tester to ensure they are still reliable. These will wear out eventually; especially the heal straps.

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#67164

ESD Protection - Hair | 30 August, 2012

Appreciate all the replies. We have a good system in place with ESD tile floor, grounded systems/benches/etc and heel and wrist strap usage and monitoring. Good training program as well. We've recently upgraded to the 2007 version of the ANSI 20.20 standard and are as compliant as most. This hair thing is one new policy that is making waves as we have a fair number of folks with longer hair. The requirement we are trying to enforce is having people with hair beyond shoulder length to pull their hair back into a pony tail or some such to keep hair from the front of the body where it could be in close proximity to product. Seems reasonable enough but the drama over it has some here rethinking the policy. This is where a specific standard would help to support our policy. There may not be an industry standard but if your companies address this issue, I'd like to hear the specifics of that.

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#67165

ESD Protection - Hair | 30 August, 2012

We have plenty of people with longer hair. This has never been an issue and there is no evidence it ever has been. Like I said, as long as your facility is following proper ESD protection protocol, which it appears you are, why the fuss? As long as your people are using proper ESD protection, there should not be any static build-up in their hair. Thus, no ESD damage done to your product. I understand your concern, but I believe it is unfounded. My opinion would be just the opposite if you did not have an ESD program.

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#67166

ESD Protection - Hair | 30 August, 2012

So, someone walks into the work area from outside [or where ever]. Presumably, there is a measurable charge on their hair. After they sit at his / her work station and strapup, is there still a charge on their hair? ... I don't know, but it wouldn't be difficult to measure with a field meter.

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#67167

ESD Protection - Hair | 30 August, 2012

Presumably, I would think not, if they are strapped up. The charge in their hair should dissipate. If not, you could make the same argument for one's clothing, couldn't you?

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#67169

ESD Protection - Hair | 30 August, 2012

If the goal is to get employees to pull back their hair, I would use the "one hair can contaminate the process..." argument instead of potential ESD danger. Then offer them a choice, either pull back your hair or get a hair net (or hair bag). I don't know anyone that would opt for the hair net.

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#67170

ESD Protection - Hair | 30 August, 2012

It should also be noted that if you can control your humidity, you can reduce the chance of static build-up. Do you monitor the humidity in your facility? This alone, can be the greatest contributor to static build-up and ESD damage.

But back to the point of long hair, I will have to crawfish a bit here. I found this article which states, "Be aware of synthetic clothing as it can contain static charges. Long hair can really retain a charge and a grounding strap on a persons body will not discharge your hair. So if you have long hair be sure not to rub it across any components." The entire article can be found here.

http://www.texndixie.com/esd.htm

I don't know if he refers to a study or not and you can take it for what it's worth. I have no reason to doubt what the author claims, but I too would like to see a study related to the matter to prove this out. Perhaps you can find other sources out there that support your argument as this one does. That being the case, your folks will just have to get used to the change. So based on this read, it supports your conclusion about long hair.

DaveF, It appears you may be correct.

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#67171

ESD Protection - Hair | 30 August, 2012

Check these reports, books, documents ... • ESD: From A To Z - Page 255 - Google Books Result books.google.com/books?isbn=0412083817 John M. Kolyer, Donald Watson - 1995 - Technology & Engineering - 338 pages Long hair will constantly recharge as it swings around, and the resulting field could cause damage by the FIM before air ions neutralize the charge. The best ... • DVD-55C ESD Control for IT and Electronics Service Technicians www.ipctraining.org/dvd/55c/script.pdf File Format: PDF/Adobe Acrobat - Quick View do to fix something when in a short time ESD damage may cause a sensitive component to fail? ESD is one of .... It may also be important to tie back long hair. • Electro Static Discharge www.texndixie.com/esd.htm The most obvious problem with ESD is damage to an electronic component. ... Long hair can really retain a charge and a grounding strap on a persons body will ... • CET1171 - Electricity and Electrostatic Discharge pcrepairclass.tripod.com/cgi-bin/main00.pl?Z=./_cet1171/lab2... The student will learn how to prevent ESD damage to the PC primarily by properly using an ..... Remove jewelry, tie back long hair, roll up long sleeves. 6. Put on ... • CompTIA A+ Complete Deluxe Study Guide: Exams 220-701 (Essentials) ... - Page 11-75 - Google Books Result books.google.com/books?isbn=1118058739 Quentin Docter, Emmett Dulaney, Toby Skandier - 2011 - Computers - 1152 pages However, computer equipment can be damaged with as little as 100 volts. ... C. Antistatic wrist straps, bags (for parts), and floor mats can all help reduce the risk of ESD. There are no antistatic hair nets (but if you have long hair, it's best to tie it ... • CIS 286 A+ Preparation elearn.albanytech.edu/.../220-701%20Domain%206.... Electrostatic discharge (ESD) can cause problems such as making a computer hang or reboot. ... This charge can, and often does, damage electronic components. ... Long hair or dangling cloth inside an open computer case is asking for ... • [PDF] DVD-11C General Safety in Electronics Assembly www.ipctraining.org/dvd/11c/script.pdf File Format: PDF/Adobe Acrobat - Quick View Long, free-flowing hair can also create static electricity charges which can damage assembly components. For complete information on controlling ESD, refer to ...

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#67172

ESD Protection - Hair | 30 August, 2012

My first question is how many failures have you seen due to hair length I will bet zero. So upsetting your employees for something that will not reduce your failure rate by one board is pointless. However someone mentioned hair in the process that i agree with. We have customers that would complain if they had hairs in the final packaging. I do get worked up about ESD. The reality is ESD failures at companies are always last on the list or do not exist. But companies spend a fortune on ESD instead on equipment or training that would truly reduce there failures. Even if you had a true ESD failure so what. I have seen companies have a 1000 failures 1 may be ESD and they go bananas and nobody seems to care about the other 999.

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#67173

ESD Protection - Hair | 30 August, 2012

How many failures? This is hard to quantify. How could you unless you witnessed a spark and all of a sudden the product no longer works. The truth is you could have a discharge and not even know it. It could brush against your clothing, or as we have just learned, your hair. You could even use your finger and not feel any discharge. The real problem with ESD is it can go unnoticed and undetected and degrade electronic components. They can work for a while, but then have a catastrophic failure instantly. The large ESD occurrences are pretty easy to spot when you have multiple "defective" ICs on a new production unit. But this is not always the case. You must spend money on ESD to prevent ESD, so I don't know what training or steps you could take to prevent it. So what if you had an ESD failure? The fact that a company has one ESD failure is cause for concern. How many discharges are occurring that go unnoticed? Just because a product is working doesn't mean it wasn't exposed to ESD.

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#67176

ESD Protection - Hair | 30 August, 2012

And that is where I see the problem. When companies have failures that are unexplained they blame ESD. It’s the scapegoat failure. And the industry through fear has us so paranoid We have companies worrying whether if your hair is 2 inches long or 3 inches long that could cause the catastrophic failure that will end your company. Where is it going to end I lay awake every night worrying about that stray positively charged particle floating around the shop just waiting to blow up a board. I am not picking on Reese this is more directed at the industry. Heck if we are worried about catastrophic failures what about tin Wiskering that’s the real threat not esd

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#67179

ESD Protection - Hair | 30 August, 2012

I'm not saying that any unexplained failure is caused by ESD and I certainly am not promoting fear. I sleep very well at night (except after eating Mexican food, which can cause discharges as well). What I am saying is that ESD is a real threat and can cause undetectable damage which can shorten the life of the product. My concern was with your statement that any noticeable static discharge need not be of concern. This is an indication that there is a problem on the production floor that needs to be addressed (the operator is not wearing a ground strap, the ground strap has quit functioning, or they are not properly grounded). When I feel ESD, I'm looking for my ground strap, because I forgot to put it on, or my skin is too dry, which is why we test them twice daily. Is this out of line? You made it sound as though you should ignore occurrences of ESD and it's no big deal. My complaint was with your complacency. Companies should take precautions where ESD is concerned; especially when there is a confirmed discharge.

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#67184

ESD Protection - Hair | 31 August, 2012

We actually use a turnstyle that you'd see in a subway terminal, connected to an ESD Tester. All operators must pass through this turnstyle everytime they step out onto the production floor. If they don't pass the ESD Test, the turnstyle will not allow them to pass.

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#67185

ESD Protection - Hair | 31 August, 2012

Yes, I've heard of these systems. That's one way to ensure everyone adheres to the ESD policy. Hmmm...starting to get an idea for my next project.

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#67190

ESD Protection - Hair | 1 September, 2012

On charge dissipating from clothing or not: It doesn't dissipate from some clothing. That's why people in assembly shops were cotton lab coats or ground-able material shirts.

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#67191

ESD Protection - Hair | 1 September, 2012

My statement about clothing was to make a point regarding hair. If you consider hair as holding a charge, than you must regard clothing in the same light. I'm not sure what your point is regarding cotton clothing in assembly. I would guess wearing an electrically neutral cloth would be better than polyester, but those individuals would have proper grounding is my guess.

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