Have your children
or Grandchildren played on the slides at fast food
restaurants
such as McDonald's or Burger King? If so, then you have heard the
"zaps" and "pops" as they discharge to the metal
bolts in the plastic tunnels. If you have been at the end of the slide
to catch them, then you have also felt the discharges.
These plastic
slides especially in the drier months of the year charge children
up to very high static potentials. Voltages in excess of 60,000
Volts
have been measured in our tests. These high static charges can give
the children painful and sometimes visible "zaps." During
our study of the problem, we were told by one little girl as we tried
to measure her charge: "don't touch that, it's hot!" She
was pointing toward one of the metal bolt heads at the end of the
slide. What she perceived as "hot" was the static discharge
she and every child gets each time they come down the slide.
Most children
do not understand the problem. They just know something
hurts.
With the problem, one would think the kids would make a game of it.
It would seem that they would be ready at the bottom of the slide
waiting to "zap" their friends as they exit. One kindergarten
teacher told us that they do not do this because the "zapper"
gets more a jolt than the "zappee." This has not been confirmed.
So,
what do we do about it? Is it even a problem?
It does not seem
to inhibit the children from having fun. However, some
children
we observed have shown significant red marks where the discharges
took place. It is our opinion that the problem is
one of comfort and annoyance. It should not take place and does not
need to take place.
Solution:
We solved the problem (for the most part) by mixing some fabric softener
with water in a spray bottle (ratio about 80% water /20% fabric softener).
We misted the backs of the clothes of the children in the test. This
reduced the level of the problem. The more the kids slid down the
slides, the more the static was reduced as the plastic became coated
with the residual fabric softener.
Comments the ESD Journal has received on this
article:
"Another and more permanent solution would be
to install ionization blowers directing air into the slide to reduce
the static build up.
Having children of my own I have experienced the problem
a great deal. An ionization blower is a safe repeatable solution to
the problem."
Peter Mariani
"I have experienced this situation myself, when taking my daughter
to an outdoor park. It was during a warm day here in Phoenix, (85
deg) with humidity around 15%. I went on a plastic slide, and could
feel and hear the charges building up as I went down. I put my hands
out at the end to stop, and brushed by one of the bolts, getting a
painful zap! Since electrostatics is a hobby of mine, I was amused
that I had discovered an electrostatic generator at the park."
Peter Ledlie
