Safety Instructions and Disclaimer

I know that the following tips are always somewhat annoying and seem unnecessary. But unfortunately, many people who knew "better" have lost eyes, fingers or other things or injured themselves due to carelessness. So please take five minutes to read the safety instructions. Because even the coolest project is not worth an injury.

The projects described here are designed for development tasks, research, teaching purposes and prototype construction only! You are responsible for compliance with the technical regulations.

Hazards due to electrical voltage or current:

When handling products that come into contact with electrical voltage, you must observe the applicable VDE regulations, in particular VDE 0100, VDE 0550/0551, VDE 0700, VDE 0711 and VDE 0860. Never work under voltage. If you are not sure whether voltage is present, use a voltmeter to check that there is no voltage. Also note that some components can store electrical energy. Therefore, make sure you wait at least five minutes after disconnecting a device from the power supply before opening the housing or working on the circuit.

Live cables or lines to which the appliance, component or assembly is connected must always be checked for insulation faults or breaks. If a fault is detected in the supply line, the appliance must be taken out of operation immediately until the faulty line has been replaced. When using components or assemblies, strict compliance with the characteristic data for electrical variables specified in the associated description must always be ensured. If it is not clear to the non-commercial end user from a given description which electrical characteristics apply to a component or assembly, how external wiring is to be carried out or which external components or additional devices may be connected and which connection values these external components may have, a specialist must always be asked for information. Before commissioning a device, it must generally be checked whether this device or module is fundamentally suitable for the application for which it is to be used!

In case of doubt, it is essential to consult specialists, experts or the manufacturers of the assemblies used!

Dangers due to high temperatures

Please also note that soldering irons, hot glue guns, hot glue and hot air guns can become very hot (up to 500°C) in certain places. Pay particular attention when working with such tools and create a quiet and tidy working environment.
Use a heat-resistant base when working and never leave hot tools unattended or near flammable materials. A readily available fire extinguisher is also a very good investment.

GDanger from sharp-edged objects

Please also note that carpet knives, scalpels, glass edges, drills, SMD tweezers and workpieces can be sharp and very pointed. Always work "away from the body" and make sure that you never hit a body part or other sensitive objects if you slip with the knife (etc.).
If you cut off component legs, pin headers or similar, make sure that the pieces you cut off fly very far and can also hit your eyes. Wear safety goggles if necessary.

Dangers from small objects

Many components are very small and can easily be swallowed by children! Make sure that small children are not or will not be able to reach these components, as they can easily be swallowed or inhaled.

Hazards from machines and rotating masses/machine parts

When working with machines, please always make sure that you wear safety goggles and hearing protection if necessary. If you are not sure whether you need safety goggles or hearing protection, it is better to wear both. Safety goggles are easier to take off after work than replacing an injured eye. Loud noises and environments often only show their consequences years or decades later. That's why you should avoid any loud environment at all costs or protect yourself accordingly.

With fast-rotating machines, you may need to take off your gloves and make sure that no part of your clothing can be pulled into the machine. The cords of hoodies or long hair in particular tend to get caught in machines. What can be particularly disastrous is that the machine can then pull your head/face into the machine. Loose-fitting shirt or jacket sleeves can also be easily caught by rotating machine parts. So make absolutely sure that nothing of yours can be caught in any way by the machine or otherwise become entangled. If possible, try to cover as many rotating parts of the machines as possible so that contact is not possible in the first place.

If you have to guide a workpiece by hand, always make sure to use an extension and keep all parts of your body as far away from the danger zone as possible. This applies in particular to circular saws or other material-removing machines.

Dangers due to data loss

Data loss is not really a danger in the private sector. At least, data loss in the private sector only rarely poses a danger to people.
However, data loss is almost always quite annoying. Because even in the best-case scenario, at least some time is needed to undo the consequences of the data loss. Restoring a database backup, for example, takes quite a while depending on the size of the database.
However, there are also cases where this is no longer possible. If you have deleted your family photos from the last 20 years without first creating a backup, this data will be lost forever.
This is particularly tragic for photos or other personal documents.
It is therefore important to make backups of all relevant files as often as possible and necessary. If you make potentially critical changes (which could lead to data loss) to a system, make a backup beforehand. Even if you think "Oh, it'll be fine". Backups are the only effective way to prevent permanent data loss. Therefore: Regular backups of all important files will ultimately save you time, nerves and often money.

Dangers due to inadequate ventilation

Air-polluting vapors, mist, smoke and dust can irritate or injure the eyes, respiratory tract and skin. These are created, for example, when cleaning objects, gluing, soldering, welding, filing, cutting, grinding, sawing, milling, polishing and also during 3D printing.

Therefore, make sure that you always work in a well-ventilated area when carrying out this work. Work involving large amounts of fumes should always be carried out outdoors if possible. If this is not possible, you should ensure that the resulting contaminants are extracted. In any case, avoid even brief inhalation of these air pollutants.

Danger from light flashes and flickering

Some people may experience epileptic seizures when exposed to certain light frequencies, flickering light sources or geometric shapes and patterns. Certain light frequencies can trigger an epileptic seizure in these people. Commercially available LEDs or other light sources can also generate these light frequencies.

If in doubt, consult a doctor if you or one of your family members suffers from epilepsy before carrying out work where flashes of light may occur. Stop work involving flashes of light immediately and consult a doctor if any of the following symptoms occur: visual disturbances, eye and muscle twitching, loss of consciousness, loss of orientation, involuntary movements and convulsions.

Dangers from handling permanent magnets

Permanent magnets made of NdFeB ("neodymium magnets") are products manufactured using the sintering process that are brittle due to the manufacturing process and their composition. They should be handled with particular care to avoid damaging or even breaking the magnet. Particular care should be taken in the vicinity of other magnets, steel, iron or all other materials that the magnet could attract, to ensure that it does not strike the respective material abruptly. Wearing safety goggles is recommended to protect the eyes in particular from any flying splinters.

It is therefore advisable to apply the magnets to the adhesive surface with great care, if possible by pushing or kinking them. Never leave magnets loose on a non-metallic surface. The magnets could attract each other in an uncontrolled manner, causing damage and even splintering. It is therefore advisable to always store magnets on an adhesive surface or folded into a stack.

The strong attraction of magnets can lead to serious injuries to fingers or other parts of the body if handled carelessly. This can result in crushing injuries in particular, but also broken bones. If in doubt, always assume that the magnet in question is unexpectedly powerful.

The magnetic fields of permanent magnets can - depending on the distance - influence the function of technical devices. This applies in particular to pacemakers. People with pacemakers should therefore not be exposed to magnetic fields. Wristwatches, cell phones or TV sets can also be affected by the magnetic field of a magnet.

Magnetic fields are capable of erasing data from magnetic data carriers such as floppy disks, hard disks, bank cards and credit cards, rendering them unusable. Permanent magnets must therefore be kept away from such data carriers.

General tip for safe working

Always be attentive during all work and work calmly and conscientiously. Take regular breaks. Think before you do something. If you need help, get help. It is better to ask too many questions than too few. Don't take any unnecessary risks!

Sources and further information

Here you will find some more information and also links to reports on real accidents or "near misses". You can learn a lot from the accidents or near-accidents of others.

Saving Your Vision From Super Glue In The Eyes
Hack Safely: Fire Safety in the Home Shop
Books You Should Read: Feynman's Appendix to the Challenger Disaster Report
MCAS and the 737: When Small Changes have Huge Consequences
New Research Sheds Light on 3D Printing Fumes