UPDATE: I am mainly interested in learning about vintage chips, ics, cpus etc, mainly non-soldered chips. It would also be interesting to know about any other component (i.e., capacitor) that could have been near a soldered chip that could cause an issue (might still be broad, since computers run everything/the chips could have been used elsewhere besides in computers).

Taking from my previous question here Are there dangers to humans from PCB/Circuit Corrosion?

I am curious if there are special precautions one should take when dealing with old/vintage electronics?

From my understanding current electronics are all made with lead-free solder, while older equipment (and even current hobbyist equip) will contain lead solder, which I'm not sure if that is a worry, but some comments were suggestion that there could be "lead-dust...." in some situations, and not sure if handling will cause issues (maybe the solder is breaking down over time, not sure if it does that?).

There is also the worry of corrosion and other nasties that could be on the circuits.

So my question is, when dealing with vintage/old electronics that might or might not be contaminated with nasties, are there specific handling instructions we should take note of? obviously when dealing with corrosion and other build up of nasties we should be wearing protection, but what about dealing with boards/circuits that are in pristine new-line condition?

EDIT: Thanks for the answers so far, and even though there isn't a lot of handling instructions, I appreciate being told what nasty chemicals I should look out for, and what.

I have edited the question a bit to try to be "less broad."

  • \$\begingroup\$ I don’t think there are any vintage chips and cpus, since those have only been around since the 70’s. \$\endgroup\$
    – JDługosz
    Jan 18, 2017 at 5:10
  • 1
    \$\begingroup\$ @JDługosz Well... What exactly do you consider "vintage?" From what I've heard about "Vintage" cars, is that a car is considered a "Vintage Car" if it is at least 30 years old, which puts us at 1987, which is kind of scary. If it's the same for electronics then there should be at least 20 years before that labeled "vintage chips." A quick Google search shows the Intel 4004 is from 1971, so there should be some chips made in the 60s as well, maybe even late 50's. Not sure what companies such as Fairchild or Sperry Rand were doing back then. \$\endgroup\$
    – XaolingBao
    Jan 18, 2017 at 7:11
  • \$\begingroup\$ I guess in the world of electronics chips and cpus are relatively new compared to some things. Not sure how far back some of these materials go, but probably into the 30's and before. I could be very wrong though as I am in no way an expert. \$\endgroup\$
    – XaolingBao
    Jan 18, 2017 at 7:13
  • 1
    \$\begingroup\$ Appliances that an antique dealer would call vintage use tubes and Bakelite. Digging into it, I see statements against a version used by some auction sellers that less old than antique “or your gran”. The general dictionary meaning doesn’t refer to specific age at all! \$\endgroup\$
    – JDługosz
    Jan 18, 2017 at 7:20
  • 1
    \$\begingroup\$ @XaolingBao , actually it only has to be 25 years old. even scarier given that the internet was around then! \$\endgroup\$
    – dalearn
    Jan 18, 2017 at 16:25

4 Answers 4


A loose list. I'm torn between this question being far too broad and far too interesting.

What I shall clearly not do is address the physiological effects of chemical compounds. Just so much: don't downplay the dangers of things like lead poisoning. It's dangerous. Keep your hands clean, don't eat while handling equipment, standard etiquette.

I can't also give you good handling advice. In fact, it's simple: Old electronics can contain hazardous material. There's national standards on how such must be handled. Don't settle for less "just because you're a hobbyist", "small entrepreneur" or "will be doing this for only a short time".

  • Mercury and Cadmium batteries, old batteries tend too "bleed" those
  • Lead migrated from solder joints, contained in particles ("dust")
  • Bromine-based flame retardants permeating everything, especially printed circuit boards in the pre-glass fibre era
  • Asbestos in the isolation of temperature-controlled components
  • Chromium in lacquers
  • DEHP, BBP, DBP, DIBP as abundant plasticizers in polymers
  • Boric acid in electrolytes of capacitors
  • Fire hazards due to aged capacitors
  • Electrocution hazard due to aged cable isolation, esp. in transformers
  • Microwave equipment, esp. gyrotrons and the similar contain very hazardous alloy components
  • Fire and electrocution hazard due to conductive or hygroscopic dirt accumulations

Device type-specific dangers of common appliances:

  • CRT TVs contain high voltage supplies
  • damaged CRTs can implode, scattering very sharp glass shrapnell. Security of old Cathode Ray Tubes is not up to modern standards.
  • CRTs emit X-Ray radiation. Shielding only in the front. Old TVs are not up to modern standards and will cook your organs
  • Tube amplifiers have 500 V+ as acceleration voltages
  • high-powered transformers are commonly suspended in oil, which has been heavily treated with very poisonous chemicals.
  • Old fire warning systems contain radioactive material in significant amounts
  • Old gas discharge tubes may contain radioactive gas.

International references

a good idea is to look into the RoHS (Reduction of Hazardous Substances) legislation and the laws it build upon. That gives you a good idea of what used to be abundant.

  • 1
    \$\begingroup\$ "Microwave equipment, esp. gyrotrons and the similar contain very hazardous" what? \$\endgroup\$
    – JAB
    Jan 17, 2017 at 23:30
  • \$\begingroup\$ Old gas discharge tubes may contain radioactive gas. \$\endgroup\$
    – bot47
    Jan 18, 2017 at 5:51
  • \$\begingroup\$ The real danger with imploding CRTs is not the glass, but the incredibly toxic phosphor inside. \$\endgroup\$
    – TMN
    Jan 18, 2017 at 15:59
  • \$\begingroup\$ @TMN my father used to due technical service lead engineer at a CRT factory. Pretty sure the scattering of glass of a non-cased/old cased/pre-security-converns CRT is relatively dangerous. \$\endgroup\$ Jan 18, 2017 at 16:07
  • \$\begingroup\$ Wow this is super sketchy stuff here... Asbestos in temp controllers... WTF? We are looking at chips and such from what he is taking out, so I really hope that none of these were used in the sort of systems that would have any of this nasty stuff... Would you say that the chips would have been in a different part of any of these electronics, compared to the nasty stuff you mention, or is it possible that any of this stuff could have affected chips and such? I have no real clue what he has, but he's also into collecting them so it's hard to say what is from where... definitely scary. \$\endgroup\$
    – XaolingBao
    Jan 19, 2017 at 20:00

Try not to eat too many soldered joints. That should take care of the lead problem.

High voltage capacitors used to be filled with poisonous PCB oils until (quite) recently.

RF transistors often use beryllia as a heat sink material, these must not be cracked open as they might release a poisonous dust.

Valves break, releasing glass shards. CRTs are big valves, for which that goes in spades, redoubled, vulnerable.

Anything really old has had plenty of time to accumulate surface films of nasties, don't get scratched or punctured by wire ends or sharp edges.

Insulators may well have degraded, and live chassis was quite common then, so don't power something on and assume it's safe.

  • \$\begingroup\$ I thought I had replied to this, but guess not. I looked up Beryllium and it seems to be a pretty sketchy material, but it seems that it is contained within these items, so we should be safe under normal handling conditions? Is this only present in RF transistors, or in all transistors? I also read it is used in aerospace gear, so I'm assuming most of the stuff is packed inside their relative packages, and we should be safe as long as nothing is cracked open? Scary stuff for sure. \$\endgroup\$
    – XaolingBao
    Feb 10, 2017 at 23:39
  • \$\begingroup\$ Note that PCB in this answer means polychlorinated biphenyl. \$\endgroup\$ Nov 7, 2021 at 12:42

Additional to the other answers

Screws and chassis sheet metal may be Cadmium-plated. Wash hands after handling and especially do not eat while you work on old kit. (Same precaution as in any chemistry lab).

The "wax" coating on really old (pre-war?) mica capacitors and similar may actually be a PCB or PCB/wax mixture. Treat as potentially toxic, handle with gloves and do not vaporize the "wax".

Old transformers (small ones) may also be impregnated with a PCB wax but this is far less accessible than the wax coating on capacitors. Not to confuse with large old liquid-filled transformers which are a much greater hazard because they may contain liquid PCBs.

Old solid-state rectifiers (funny square multi-finned things) contain selenium and tellurium. Not particularly toxic, but I don't think I'd want to find out whether these things are capable of giving one Tellurium "poisoning". (It makes one stink of rotten garlic ... for a year or more ... victims have been known to commit suicide because of the social side-effects).

You might encounter an old mercury rectifier diode. As its name suggests, it contains mercury. If you make it active, it also gives off lots of UV light which can damage your eyes should you operate it with the cabinet open or its metal shield absent (if it ever had one). It also gives off quite a lot of hard X-rays (far more than an old CRT). I once found one about eighteen inches long (a long-forgotten component) and arranged for it to be disposed of as hazardous waste before it got broken.

Old electrolytic capacitors in equipment that has not been used for decades may explode seconds, minutes or even hours after you power it up, and spray highly caustic goop around. It's best to replace them with modern equivalents (which will be smaller). If you desperately desire to retain authenticity, then read up on how to test and recondition them before putting them back in service, then cross fingers and see below.

Bakelite can become conductive and ultimately a fire hazard, especially if it's become dusty and then stored for decades in a damp place.

So if you are renovating vintage kit with thermionic valves, always treat it as a fire or (minor) explosion hazard for the first few hours after you first re-power it, even if it seems to be working AOK! Run it with its covers on, away from anything else flammable, and with a working smoke alarm in its vicinity.

On the "don't worry" front: lead-based solder really isn't much of a hazard when melted and splashed. Just don't eat it or file it. Bear in mind that until about 20 years ago, copper plumbing was assembled using lead solder, and much of the water we drink still comes through these pipes.

Old CRTs are not a significant radiation hazard. I think this is a persistent meme because in the early 1950s there was a near-perfect correlation between rising TV ownership and rising lung cancer rates. There was a putative causal connection, but the culprit was later found to be rising cigarette consumption and TVs were exonerated. If the TV set in question has valve rectifier diodes, then these valves are a considerably greater radiation hazard than the CRT, but also not significant unless you spend hours each day crouched right next to the TV or oscilloscope.

  • \$\begingroup\$ Thanks for this. The "Tellurium poisoning" doesn't sound as bad as if you were poisoned with something else(Mercury), but committing suicide over it is definitely sad. We seem to be mostly handling Integrated circuits and chips, so I'm not sure if any of those could have been exposed to anything bad? It's hard to know, but I would assume as long as one takes precautions of gloves and possibly face mask we should be okay? It seems the really bad dangers are from capacitors and other things that would AID chips. \$\endgroup\$
    – XaolingBao
    Jan 20, 2017 at 14:49
  • \$\begingroup\$ Vintage to.me meant thermionic valve stuff pre-1960. Those sorts of solid state rectifiers went out as soon as silicon power diodes came in, plus you would have to handle a badly damaged one ir try to dismantle one to get any exposure. Also not sure whether tellurium content was significant. \$\endgroup\$
    – nigel222
    Jan 20, 2017 at 14:56
  • \$\begingroup\$ Thanks. I'm just paranoid about all of this stuff after reading about it, but it seems that the likelyhood of any dangers is very low unless you're dealing with full circuits and such, but curious how dangerous some of these chips could be that were around it. \$\endgroup\$
    – XaolingBao
    Jan 20, 2017 at 17:26

I wanted to add some comments on actually using vintage components, as opposed to merely handling them as the other answers concentrate on.

Older parts tend to be a lot less resilient in some ways, and a lot more in others. On the one hand vintage ICs are particularly prone to static damage and damage from exceeding design limits. Modern parts often have protection circuitry, especially on things like microcontroller I/O pins, but also things like thermal shut-down for regulators and clamping diodes for transceivers, that older parts lack.

On the other hand, older parts usually run at higher voltage than newer ones, so are more tolerant of things like 5V supplies which can kill modern 3V chips. On the subject of voltage, vintage parts often needed quite high voltages to operate, so beware of the danger.

More complex parts like CRTs can be killed by bad input signals, e.g. sync signal failure resulting in the beam burning the tube. Modern parts often have protection for these kinds of failures.


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