Customer concerns about 3D printing fumes – SLA, too

Responding to questions from customers about fumes produced by their 3D printers can be frustrating.

Typically, the customer offers an SDS [previously called a Material Safety Data Sheet] and asks for assistance in interpreting it.

As you know, individual components in fumes may require specific types of filtration in order to capture them before they can be inhaled.

Each chemical’s SDS should identify any hazards associated with the chemical, including respiratory hazards.

Then what happens?

So one of our applications specialists takes a look at the Data Sheet and finds:

1. Despite GHS requirements, the document is old and incomplete.

OR

2. The ‘data sheet’ proffered is not a Safety Data Sheet and looks more like a brochure.

OR

3. The SDS’ Section 3, Composition/information on ingredients, simply says, Proprietary.

We encounter this often in our SLA 3D printing research.

SLA 3D printing

Stereo lithography [SLA] printing is a form of 3D printing that uses lasers and liquid polymers that react to light.

SLA does not melt a solid polymer filament in order to print it.

Rather, SLA methods use a laser to cause light-sensitive liquid polymer to harden and build the final object one layer at a time.

Vats

Online photos of SLA printers show vats of varied sizes containing liquid polymer.

No lids on those vats, although some printer models have cabinets that enclose the vat and laser as the laser fires into it.

Any fumes trapped inside the cabinet during printing would be released when the lid is opened to retrieve the final printed object.

We want to know: What pulls hazardous chemical fumes away from the operator?

Cleaning a SLA object involves chemicals, too

SLA proponents like the process because of its accuracy. Turns out, its best appearance requires a little cleaning.

We found online recommendations to use tripropylene glycol [mono] methyl ether; isopropyl alcohol; an unnamed “chemical bath;” or a solution with caustic soda [lye; sodium hydroxide].

Do you think your lungs appreciate this doubling down on fumes? Do you think there are studies that indicate specific combinations of fumes are harmless for someone your age, your gender? Because there aren’t.

3D printing technologies are new, evolving & OSHA exposure limits are 40 years old

PEL is an acronym for Permissible Exposure Limits, the acceptable amount of a substance in the air, a form of protection from hazardous chemicals.

“The intent of PELs is to protect workers from the health effects of hazardous chemicals.

“Unfortunately, most of our PELS were adopted more than 40 years ago and new scientific data, industrial experience and developments in technology clearly indicate that, in many instances, these mandatory limits are not sufficiently protective of worker health.”

Dr. David Michaels
US Department of Labor

OSHA has published annotated PEL tables that include more up-to-date recommendations by a non-profit association of industrial hygienists and the state of California’s industrial relations department, also known as CAL/OSHA.

In some cases, newer PELs are big reductions of the older PELs.

For example, one 3D SLA printer manufacturer uses a light-sensitive polymer they identify as “methacrylic ester monomers”.

Methacrylic ester monomers are also known as methacrylate monomers and methyl methacrylate.

OSHA’s 40-year-old PEL is 100 ppm, or 100 parts of methyl methacrylate to 1 million parts of air.

The PEL recommended by both CAL/OSHA and professional industrial hygienists is 50 ppm, or 50 parts of methyl methacrylate to 1 million parts of air

See the difference? Do you think your lungs might know the difference?

Exposure to hazardous substances is not a joke

We want you to think about your future.

Certainly, 3D printing is predicted to have a big impact on the futures of manufacturing, from big companies to one-person shops.

Today’s eleven-year-olds may be working around and with 3D printing from childhood through the span of their professional lives.

Protect your lungs from disease that starts with dirty air you breathe today, even though you may not feel the impact until years into the future.

Project yourself into the future, protect you lungs today.
Resources

Globally Harmonized System (GHS)
https://www.aiha.org/localsections/html/nevada/GHS%20FOR%20LV%20SHOW.pdf

3D Printing Processes
https://thre3d.com/how-it-works/3d-printing-process

New 3-D Printers that Don’t Suck
http://www.wired.com/2012/07/3-d-printers-that-dont-suck/

How Stereolithography (SLA) Works
https://thre3d.com/how-it-works/light-photopolymerization/stereolithography-sla

A Guide to The Globally Harmonized System of Classification and Labeling Chemicals (GHS)
https://www.osha.gov/dsg/hazcom/ghs.html

ProtoGen 18420, liquid ABS-like photopolymer
http://www.slideshare.net/pservando/protogen-18420-material-sheet

Super quick cleaning method for resin prints
http://blog.madesolid.com/2014/04/quick-cleaning-method/

OSHA Releases New Resources to Help Employers Protect Workers from Hazardous Chemicals
http://social.dol.gov/blog/osha-releases-new-resources-to-help-employers-protect-workers-hazardous-chemicals/

Observational report: [exceptional] dog sniffs out UFP

Portrait of the world's most handsome dog, Willy Bones Jr.

Willy Bones Jr, Houston

Willy Bones Jr lives and walks in an older Houston neighborhood.

Joy, his human companion, roams the neighborhood with him.

On the way to their favorite walking path, they cross a busy street near an elementary school.

That means they’ve been near said street when diesel-burning vehicles pass by, including school buses and dump trucks.

What does a sneeze communicate?

It seems observationally notable that Willy always sneezes when a dump truck goes by but never sneezes when a school bus passes. His reaction is unexpected because both burn diesel fuel in their engines.

The school buses, however, are much less odiferous — perhaps there’s more to the story.

DPM, particulate filters, low-sulfur fuel, ultrafine particles

Turns out, Houston school districts use low-sulfur fuels and have retrofitted buses with filters that trap diesel particulate (DPM) so that kids don’t inhale it outside the bus or in the bus.

DPM is also UFP:

“When released into the atmosphere, DPM can take the form of individual particles or chain aggregates, with most in the invisible sub-micrometer range of 100 nanometers, also known as ultrafine particles (UFP) or PM0.1.”  

wikipedia.org

Because UFP is so very small, it can easily be inhaled. It is hoped the wise and wonderful Willy sneezes out all the UFP he encounters.

UFP in kid-friendly environments

3D printers produce UFP.

We were very happy to work with the Children’s Museum of Houston to install fume extractors for their 3D printer, laser cutter and soldering stations.

Their Maker Annex is designed to promote tinkering and creativity in a safe environment.

Want to talk about UFP in your space?

Give Sentry Air a call at 800.799.4609. You can also email us sales@sentryair.com, visit our website or fill out the feedback form below.