Introduction: DIY Plastic PPE Gown

By Richmond Pediatrics
About: Infant, child, and adolescent medicine in Richmond Beach, WA, USA.

With highly contagious coronavirus (COVID19) rapidly spreading throughout the world, many health care providers are running out of disposable isolation gowns. These gowns, a type of “Personal Protective Equipment” (PPE), are important for doctors and nurses to wear while examining patients to determine if they are infected, or while treating infected patients.

The sudden increase in global demand for PPE and interrupted supply lines have led to a critical shortage of these gowns. You can use this instructable to help meet this need at a cost of less than 50 cents per gown. In comparison, our pediatric clinic in Seattle has been buying rain ponchos for about a dollar each.

This instructable is optimized for a "universal" gown that should work for any body size. It has an arm span of 6' allowing enough material at the ends of the sleeves to poke a thumb hole and tuck the wrists into a glove with sufficient overlap. It hangs about 4' down from the shoulders, just below the knee on our tallest doctors.

This design uses plastic sheeting that is 0.7-mil thick. We found this thickness optimal because: the cost per gown is low; the sheeting is thin enough to allow thumb holes to be punctured easily near the ends of each sleeve before donning gloves; durability is high enough for reliable single use and for thumb holes not to tear; and material is flexible enough for us to don and doff the PPE safely per CDC guidelines. While this gown is closed on the back by default, some providers may prefer to slit the back leaving easy-to-break connections near the neck, waist, or knees to make doffing even easier.

Supplies

Update 4/1/20: use a clothes iron instead of a heat gun! (instructions also updated)

  • 12' x 400' roll of 0.7 mil plastic sheeting (e.g. HDX from Home Depot)
  • large piece of cardboard, or plywood sheet (at least 4'x6', but ideally 4' x 8')
  • measuring tape & straight edge
  • indelible marker (e.g. thick Sharpie)
  • sharp scissors (or box cutter)
  • clothes iron (or heat gun)
  • parchment paper
  • 1 gallon paint can

Step 1: Prepare Supplies, Tools, & Template

This big roll of plastic is going to create 100 gowns! To make the production process more efficient, it helps to make a template or pattern. We like using a big piece of cardboard, or a standard 4' x 8' piece of plywood or sheetrock. You could also draw on paper or or chalk on a cement floor in your garage or basement. Or work outside if the weather is nice! The important thing is a smooth surface, especially along the seam you're going to melt or "weld" shut, and a material that won't get stuck to the hot plastic.


You can see the important parts of the template in the photos of our first cardboard version and the improved, smoother plywood version. It helps to have at least a center line and a reference line where the top of the shoulders will be. First draw a 6' long reference line (or use the top of the plywood sheet). Then make a central mark (at 3' from either end of the reference line) and scribe your center line down from there.

Next, you can scribe the curves to define the sleeves and torso of the gown. We measured down 7" from the shoulder reference line to get a wrist girth that allows for easy donning and doffing, and minimizes the extra material to be tucked into the glove. We measured ~15" out from the center line to define the width of the gown near the knees. The curve in between is best found by having someone lie down so you can trace their shape loosely (with a ~6-8" buffer from their body). Be more generous in the armpit area and less generous at the wrist and waist-to-knees section (though a little flair out below the waist provides legroom when walking and crouching).

Step 2: Cut Desired Length From Roll

Using the 12' wide roll, we're going to measure out an 8' length. Later we'll fold this 8' length in half to form the front and back of the gown. You can use your measuring tape for this step, or another measurement reference (e.g. the length of a piece of plywood or a mark on your big piece of cardboard).

Tips to speed up production:

  1. Hang your roll on a broomstick so you can unroll new material easily.
  2. Learn to "push" the sharp scissors through the plastic with the blades half open once you've got your cut started. It's a lot faster than opening and closing the scissors as you cut, plus it leaves less jagged edges.

  3. Instead of using scissors, put a 2"x6" wooden board on the floor next to the roll, mark a center line, and slice through the plastic sheeting along the line with sharp box cutters.

Step 3: Cut a Rectangular Shape & Fold It in Half

The next step is to cut the 12' width in half, forming two 6' widths that will be the arm-spans of two gowns.

There are two ways to determine where to make your cut:

  1. You can get fancy and figure out the folding pattern, and find the middle of the 12' width. It may help to number/letter the folds to determine where to cut. (As an example, the HFX folding pattern has a midline crease you can cut along -- labeled "middle of 12'" in the photo.)
  2. Alternatively you can grab a friend, unfold the full 12' width, fold it in half (like when folding a big bed sheet), and then cut along the fold.

Ether way, you'll end up with two rectangular pieces, each 6' wide and 8' long. Finally, fold the 8' side in half.

Now you should have two folded sheets, each 6' wide and 4' tall. Put one of the folded sheets down on your template with the folded edge along the top (shoulder) reference line, and make sure it is centered. Put the other folded sheet aside for now. (If you end up making an assembly line, one person should be able to generate these half sheets on their own and just stack them up next to the template.)

Step 4: Mark the Neck Hole

Use your indelible marker to draw on the plastic sheet. These lines will guide you later when you cut the neck hole.

Place your 1-gallon paint can at the intersection of the shoulder reference line and center line. Use your pen to trace around the lower half of the paint can to mark on the plastic where you'll cut the neck hole.

Step 5: Weld the Main Seams

This is the trickiest part. Move your heat source along each seam, following the curve on your template by looking through the plastic layers (and maybe parchment paper, too). The challenge is to get enough heat to melt the upper and lower layers of the folded plastic together -- forming a durable virus-proof seam -- but not so much heat that you make holes in the protective gown, cause the gown to deform from the plastic shrinking excessively as it is heated, or melt the plastic to the underlying template!

With a clothes iron the weld is pretty easy -- but don't forget some parchment paper between the plastic and your iron! (Thanks to Mathias Drogosits of Austria on the Facebook group "Open Source COVID19 Medical Supplies" for the suggestion!) We selected the highest setting (w/no steam) and worked on a sheet of plywood with a smooth finish, generating a consistent weld that is ~3x wider than with the heat gun and ~10x faster to execute. (Experiment with your iron's heat settings and the speed with which you move the iron until you get a good weld.) Also, if you're using cardboard, be careful to push down harder as you cross any folds or wrinkles in the cardboard; otherwise you may end up with a linear opening through the weld (a leak).

With a heat gun, getting a good weld can be tricky. We had the best results with the 0.7 mil sheeting by keeping the heat gun on the hot (less flow) setting, holding the tip of the gun about an inch (2.5 cm) from the plastic, and moving it at about 2 inches/sec (5 cm/sec). To prevent holes from forming, be sure to keep the gun moving and do not restrain the plastic as it shrinks in response to the heat. (The latter was very important when we experimented with 0.3 mil sheeting which shrinks dramatically, especially near the edges.)

If you don't have an iron or a heat gun, you might also try a hair straightener or hot glue gun...

Step 6: Cut Neck Hole & Trim Outside of Seams

Use your sharp scissors to cut the neck hole. Then cut off the excess sheeting 1-2" outside of the welded seams.

If your scissors are sharp enough, you can start the cut normally and then just "push" the scissors through the material. Alternatively, if you're using a plywood sheet, a box cutter might be an even faster tool for this step.

Recycle the scraps, if possible...

Step 7: Test Fit & Integrity

The last step is to try on your first gown and see how it fits. You can adjust the lines on your template to improve the next gown. (Go back to Step 1 and use different colors or line styles to reduce confusion about which lines lead to the optimal fit..)

Be sure to check to see that your welds are strong and free from any holes. It may take a few tries before you get a consistent weld that generates a nicely sealed seam. One way to test your welds is to tie off the wrists and neck tightly, blow up the gown like a balloon, and then squeeze the balloon and listen/feel for leaks. We found that welds with the clothes iron did much better on this test than with the heat gun, because the iron creates a much wider and more-continuous weld.

Health care workers may have preferences about how to doff these gowns safely. Talk with them about whether they would like a slit pre-cut up the back of the gown (e.g. with an easily-breakable tab remaining at the neck and possibly the waist).

A final note to health care providers: Please try to use commercially available, high-quality gowns for high exposure activities (i.e. aerosol-generating procedures). You may want to read the U.S. Centers for Disease Control (CDC) guidance regarding managing gowns. We are using this DIY gown for outpatient care at our outpatient pediatric clinic in combination with gloves, eye protection, and a regular surgical mask. We consider this a non-surgical gown and hope that it will be more protective than cloth gowns, other gown alternatives mentioned in the CDC document, or the rain ponchos we have been using. You may also want to reference the U.S. Food & Drug Administration's guidance on medical gowns.

Step 8: Share Your Gowns, PPE Resources, & Improvements!

Here are some resources you may find useful if you're making these gowns -- whether you're a health care provider or a good crafty Samaritan. Also, we'd welcome ideas for improving these gowns in the comments and will do our best to incorporate your feedback into the Instructable.

Sharing & making PPE resources

Additional resources for this Instructable

  • Cost computation spreadsheet indicating bulk material costs of $0.14 to $0.44/gown (Google spreadsheet, with some links to plastic sheeting suppliers)

Other resources related to medical isolation gowns