Safety: What to Watch Out For

Thermal Runaway Protection on = basic protection for every printer

An FDM printer is an electrical device with hot parts. Proper safety precautions eliminate the vast majority of risks.

Smoke / CO Detector

Install in the printer room - catches the problem early

Smart plug with monitoring

It automatically disconnects the current in case of excessive consumption or at a set time

Thermal Runaway Protection

Verify that it is enabled in the firmware (Marlin, Klipper, Prusa FW)

Unsupervised

Long prints = smart plug for timer or camera with alert

• Thermal Runaway Protection If the thermistor fails and the printer does not detect the temperature, the FW must stop printing. Verify the settings in the firmware. Prusa, Bambu and Creality have it turned on by default.

• Quality PSU: Cheap PSUs are the most common cause of fires. Replace with a Meanwell or other certified power supply at printers where the PSU was part of a cheap kit.

• Smart plug + timer: Wemo, Tasmota or TP-Link Kasa printers can disconnect the power if the print finishes or exceeds the set time. Integration with Home Assistant.

ABS fumes (styrene) are demonstrably harmful - ventilation or enclosure + filter

FDM printing releases nanoparticles and chemical fumes. Their intensity depends on the material.

PLA

Low emissions - moderate ventilation is sufficient | Odor - lactide, not dangerous

PETG

Medium emissions - ventilation recommended | Less than ABS

ABS / ASA

High styrene emissions - outside ventilation or HEPA+activated carbon required

CF/GF composites

Carbon or glass nano-fibers – HEPA filter is required, not optional

• PLA Relatively safe. An open window or switched on ventilation in the room is a sufficient precaution for most users.

• ABS / ASA Styrene fumes are a proven irritant. Print with ventilation outside or in an enclosure with HEPA + active carbon filter.

• CF and GF composites: Nano-fibers are a respiratory risk. A HEPA filter or venting to the outside is a must, not an option.

• Pets: Birds are extremely sensitive to fumes. ABS and PTFE fumes (heated above 482 °F) are lethal to birds. Printer + birds = separate rooms.

Recommended option

Mechanical and Electrical Safety – What to Keep in Mind When Working with a Printer on a Daily Basis.

• Nozzle and hotend: 392 - 500 °F during operation. Never touch with bare hands. When changing the nozzle, let it cool down or use heat-resistant gloves.

• Moving parts: Do not stick your hands into the work area when printing. Axes, toothed belts and extruder move quickly and with high force.

• Electrical connectors: Do not connect or disconnect motor connectors while running. You will damage the drivers. Always turn off the printer before any electrical interference.

• Children and animals: The printer should be kept out of the reach of children and pets during operation. Moving parts, hot parts and fumes are a risk.