Friday, February 28, 2014

EPA - Design for environment Product labeling chemical list DfE - Webinar

EPA has been updating its safer chemical ingredient list for manufactures attempting to  reduce the toxicity and  environmental impact of the chemicals used in products.   A key to the symbols for each chemical is found at the bottom of the list.

Clive Davies from the EPA will be presenting a webinar on the DfE program on March 18, 2014 1 to 2 PM CDT. 

Roland Cliff - 22 min.  Chemical Engineering Ecology

Thursday, February 20, 2014

3D printer ventilation and hazard assessment

The U of MN College of Design has a DigiFabLab 3D printing lab that opened on October 14, 2011.

Consumer Grade 3-D printers produce ultrafine nano particles.  According to a July 25, 2013 article by Nicole Bogart, Global News the hazards posed by the ultrafine particles are similar to those posed by cooking, scented candles and possibly cigarette smoke.

Michael Molitch-Hou 3D Printing industry July 29, 2013 reports on a French study that notes an increase in the number of ultrafine particles during the operation of multiple 3D printers in one room.  The particle generation is similar to that noted during cooking.  The toxicity of the particles is not known.  The authors recommend local exhaust ventilation.  A chart of the ultrafine particle production is listed below. (click to enlarge)

Sentry Air Systems provides a good background into the toxicity of 3-D printing. (ABS or PLA)

The primary chemicals used in ABS 3-D printing are Acrylonitrile, Butadiene and Styrene.  These chemicals have relatively low exposure limits ranging from 1 to 50 ppm averaged over 8  hours and 10 ppm for a 15 minute short term exposure limit for Acrylonitrile.

For information on PLA (Poly Lactic Acid) - Wikipedia  -  The material is good for containing materials at room temperature.  It will melt if used for hot beverages. 

Nano particle production ( - 2013) :  Illinois Institute of Technology researchers

PLA - lower temperature   20 billion nanoparticles per minute
ABS - higher temperature  200 billion nanoparticles per minute.

From this information it would be prudent to use local exhaust ventilation for 3D printers using ABS and HEPA filtration for PLA.