Health and Safety

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This page lists advice which can help you protect your health and that of others while manufacturing, assembling or using a printer. Another page covers the machine safety and notably the fire risks. While some people might find a lot of points self-explanatory, repetitive and/or boring, we urge you to read it fully at least once.

General advice

  • Keep a first aid kit handy. A normal first aid kit for cars should suffice, but you might want to add some (more) plasters and something to treat burns. Ideally, you'll never need it, but when you do, you'll be happy to have it.
  • Same goes for a (small) fire extinguisher.
  • When operating machines, wear protective clothing. This depends on the machine you're working on, generally you should:
    • NOT wear gloves when operating machines with rotating parts (e.g. a lathe), because the gloves could get caught in it.
    • Wear safety glasses when operating machines which produce chips. High velocity shrapnel and eyes don't mix well.
    • People wearing corrective glasses not always use safety glasses as this is unpractical and they feel already protected. However, chips may rebound on brow ridge and glass to enter eye. Velocity will be limited, but that may however end badly with hot chips.
    • Safety shoes/boots with steel caps can protect your feet from falling stuff, e.g. that anvil you were holding just a few second before.
  • Make sure you've read and understood the instruction manuals of the equipment you use.
  • Be especially careful when children are around. Don't leave them unsupervised.
    • Ask them not to touch any tools and (most importantly!) explain to them why.
    • While you're at it, get the next generation interested in RepRap.

Building your printer

Soldering

  • Some solder contains lead, wash your hands after using it. Otherwise, lead particles might make their way into your body.
  • Some solder contains soldering agents. You won't get around it, but at least try not to inhale them.
  • A soldering iron operates at temperatures between 150 and 480 °C [302 and 896 °F], don't touch anywhere but the grip/handle.

Working with electronics

  • Always do a quick visual check of the device in question before applying power to it.
  • Do not touch current-carrying parts, you might get an electric shock.
  • Do not touch electrified people, always pull the plug or turn off the mains first!
  • Water and electronics generally don't mix well.
  • Don't inhale the magic smoke. When something starts smoking, turn off the power immediately and ready your fire extinguisher.

Working with electricity

Care shall be taken while the power supply is inside your printer. Electricity kills, even professionals.

Shield all accessible parts in 110~230V. The shielding shall be independent from other parts of the printer, to be able to do very low voltage maintenance without risks.

Never work on live mains wiring.

Ground power supply and all metallic part which are at risk of being in contact with the mains in case of failure or wire breakage.

Your installation ground shall be effective. Check with a socket tester.

4-20mA breakers are compulsory from long in many countries, but old installation may not have them. Its is a vital safety and you may upgrade your installation if it is lacking.

Chemicals

Restriction of Hazardous Substance directive (ROHS)

Equipment sold in EU shall comply with EU regulation, being it an ensemble or a component. Components, as electronic board, if sold separately, does not have to be CE marked, but they shall be capable to be integrated in a CE certified product, with documentation explaining how to integrate to be CE compliant.
Notably all electronic sold in EU shall comply with the ROHS directive (no lead or other toxic heavy metals), and a lot of REPRAP components does not comply.

Acetone

Acetone is used to smooth ABS print, sometimes by heating it. Acetone is a fairly toxic chemical, which is quite volatile. Its boiling temperature is 56°C.
In addition while vaporised, it became explosive at low percentage, in a wide range (from 2 to 13% in volume).
So, for those who want to take the risk of smoothing ABS with acetone, at least do that outdoor, far from any ignition point, with the cold method, and walk away. Never boil acetone.

Filament & resins

Depending its origin, filament or resins of all plastic type may contains toxic chemicals, sometimes at high levels. There is nearly no information from most manufacturers and in a lot of countries, this is a violation of regulations. Some filament plastic are in themselves somewhat toxic while heated (ABS).

Filament sold in EU shall be CE compliant and marked as such. The CE directive about chemicals is the REACH directive, but there is no need to refer to this directive if product is CE marked. You may find on common filament spool the mark ROHS, which does not make sense as ROHS is for electrical products and cannot replace the CE mark.

Low cost filament may contains many times the allowed (in EU and USA) contents for toxic components. Dark filament may contains heavy metals (Lead and chromium). If buying cheap filament, use only natural color.

In EU, regulation impose that a MSDS (material safety datasheet) shall be available for each kind of product (filament or resin). Dye shall be taken into account in a safety datasheet. You may request them to product seller. If operating a printer in a school or any public place, getting these MSDS is imperative.

Fumes and gases from printing

Printers emit toxic fumes,VOC and ultra-fine particles. [1] [2] [3] [4] [5] [6] Also, if using cheap filament, they may emit heavy metals fumes.

VOC and ultra-fine particles could be filtered.

If you want to build your own filter, filtering odors and VOC is easily done with activated carbon filters as found in kitchen filters. Filtering ultra-fine particles is more difficult but it exist HEPA filters on some vacuum cleaners (Dyson) which could be used, but they may need more powerful fans.

There is no effective way to remove heavy metals. Ensure you source filament from reputable suppliers in the US and European Union.

Filtering the VOC

The VOC are efficiently stopped by adsorption on activated based filters. You found this kind of filters in Kitchen filters, vacuum cleaners and organic filters for respiratory masks

Filtering the ultra fine particles

These particles (lower than 0.1 microns) are completely invisible, even in a laser beam and are undetectable without specialised equipment. They could be filtered with HEPA filters. Filtering these low size particles works by adsorption. You could find such filters in some specific vacuum cleaners or in respiratory masks cartridges. The efficiency of these filters improve with time, as the filtration 'clogging' improve the filtering media.[7]

Others non filtration techniques are based upon high voltage devices.

Activated carbon

Activated carbon is burned organic compound, and the activation [8] increases the holes quantity to have larger areas. The surface is huge with approximately 1m2 par gram. This is universally used to remove components in gases or liquids. Components are attracted on the carbon media by what is called weak forces so the capture principle is physical, not chemical. It is used as powder, granulates, beads or compounded on mattress for easier handling. It is often elaborated with charcoal but could be done with other organic matter (e.g. coal or oil).

How to get rid of toxic fumes

Exhaust fumes

It is fairly simple to exhaust fumes from a printer with a computer fan. However, one of the interest of an enclosed printer is to maintain a warm temperature to improve printing and exhausting all fumes will cool the printer ambiance, and in such case you will need a recycling unit. The outlet of the duct could be sent to a filtration unit or outside the building.

Building your own recycling filters

Some have built filters while using commonly available components :

  • Filter for respiratory mask [9]
  • Filter for vacuum cleaner ('HEPA' filter)

These filters have high pressure drop and needs high pressure fans.

Simple odor removal system have also been built with charcoal filters mattress for kitchen filters as they have a very low pressure drop. Charcoal is also adsorbing most materials and particles, so it may be the simplest overall solution.

Without scientific details data, it is difficult to determine dimensions but from experimentations as described in forums and existing filtration units (see links), a guess of what could be installed for a recycling unit of a printer is:

Activated carbon filter of 250cm2 area, thickness 2cm (total volume 500 cm3 ~ 30.5 cubic inch). Same filtering volume with larger area may be more efficient, as lower speed improve efficiency. Media volume may not vary with printer dimensions, but area may be increased in order to maintain low speed with higher flowrate.
The flowrate shall be minimized to have good overall removal efficiency (the principle is adsorption, not filtration), but you need sufficient volume renewal in your printer to open it. One volume renewed in 2~5 min may be a base. Printer doors may better stay closed during 5 recycling volumes.

Using an ambient particle removal unit

It does exist filters to clean the ambient air, which may be installed aside the printer.

Already made printer enclosure or scrubber units

It does exist on the commercial market filtering enclosures or filtering block which could be adapted to your own enclosure.[10]

Filtering cartridges on commercial printers

An example of simple cartridge exchange on a commercial printer, which also gives idea about dimensions.

Operating your RepRap

  • You shall be aware of all risks presented by 3D printing, make your own safety philosophy related to your setup and try to respect your own rules. You have to organize your installation and isolate toxic or flamable products. [11]
  • RepRap works with materials at temperatures from ambient to about 300°C. You could burn yourself. Also some parts of the RepRap machine (particularly the extruder) are capable of generating quite high forces and torques - don't get your fingers in them.
  • Printers generate toxic fumes, at a level which depend from the type of plastic and its origin. If not equipped with a filtration system, A printer shall be installed in a well ventilated area and you shall not stay near the ventilation flow. Also, If you have a filtration system, the filters shall be changed at recommended manufacturer intervals.
  • Removing support materials

Use caution while using solvents to remove support materials, wearing gloves, respiratory mask and appropriate clothing.

  • Please be careful and use a double boiler when melting wax or thermoplastic. A double boiler is a set of two pans. The lower pan contains hot water, and the upper pan is placed in the lower pan.
    • If you do not have a double boiler, put your wax or thermoplastic in a soup can and place that in a saucepan half full of water. Place the saucepan on your stovetop or hot plate and heat normally.


other Risks

Handgun Test:

  • Every manufacturing technology that humanity has ever come up with has been used to make weapons, and doubtless RepRap will be no exception. There is no absolute way to stop this, any more than one could stop someone buying a second-hand lathe on eBay and using that to turn up all sorts of very nasty objects. However, the RepRap researchers will work actively to inhibit and to subvert the use of RepRap for weapons production, whether by individuals, companies, or governments. And we will remove any such designs from this site. At least RepRap is not very suited to weapons manufacture - it tends to work with more subtle and delicate materials. Give people an internal combustion engine and a few will make tanks; but many more will make ambulances.


Laser radiation

First: Read Wikipedias section on Laser radiation hazards.
Second: Make sure you have adequate safety glasses for the laser in question!

See also: Laser Safety

References

  1. ↑ http://www.sciencedirect.com/science/article/pii/S1352231013005086 Ultrafine particle emissions from desktop 3D printers
  2. ↑ http://pubs.acs.org/doi/pdf/10.1021/acs.est.5b04983 Emissions of Ultrafine Particles and Volatile Organic Compounds from Commercially Available Desktop Three-Dimensional Printers with Multiple Filaments
  3. ↑ http://www.3dsafety.org/3dsafety/download/mf2015_eng.pdf Gas evolution during FDM 3D printing and health impact
  4. ↑ http://built-envi.com/portfolio/ultrafine-particle-emissions-from-3d-printers/ Gas and particles emissions from 3D printers
  5. ↑ http://3dprintingindustry.com/2015/10/28/toxic-abs-pla-fumes-3dsafety-org-inquires-vocs/ How toxic are ABS and PLA fumes ?
  6. ↑ http://sentryair.com/blog/health/3d-printing-are-there-particles-how-about-fumes/ 3D printing are there particles how about fumes
  7. ↑ http://www.berriman-usa.com/tutorial_2_air_purifiers.htm
  8. ↑ http://www.buyactivatedcharcoal.com/how_to_make_activated_charcoal
  9. ↑ http://www.thingiverse.com/thing:125264 Scrubber with mask filter
  10. ↑ http://3dprintclean.com
  11. ↑ http://www.cmu.edu/ehs/fact-sheets/3D-Printing-Safety.pdf 3D printing safety

See also

External links

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