December 29, 1999
Dear School Official:
ADVISORY ON ASBESTOS-CONTAINING MATERIALS
USED ON PLAYGROUNDS AND OTHER SURFACES
In 1990, the California Air Resources Board (ARB) issued an advisory regarding the use of asbestos-containing serpentine
rock in schoolyards, playgrounds, and other surfacing applications. The advisory was issued because of the potential
health risk for school children exposed to asbestos contained in serpentine rock. The ARB is re-issuing their advisory
to alert school officials of this continuing potential exposure and health risk.
While we believe that the problem is limited to relatively few schools, we suggest that playgrounds, unpaved parking
areas, unpaved roads on school grounds, bus stops, and day-care centers should be inspected to determine if they
are surfaced with asbestos-containing serpentine rock. The enclosed information contains a series of Fact
Sheets prepared by ARB staff. Fact Sheet #2 entitled "School Advisory for Naturally-Occurring
Asbestos" contains information specific for schools. The other Fact Sheets provide additional information
on serpentine rock, health effects of asbestos exposures, ways to control asbestos dust, and monitoring for asbestos.
If your school grounds are covered with asphalt, concrete, or grass, this advisory should be of no concern to your
school. However, if there are areas surfaced with crushed rock or gravel that is grayish-green to bluish-black
in color, we recommend that you have a registered geologist identify whether the material is serpentine rock. If
the material is serpentine rock, it should be tested using ARB Test Method 435 to determine
if asbestos is present. If asbestos is found, we recommend you consider sealing the material, remove it, or cover
it with non-asbestos-containing materials to prevent disturbance of the serpentine rock. You may also want to consult
with your local county health officials.
Questions regarding this advisory should be directed to your county air pollution control district (see enclosed
phone list) or Mr. Jerry Martin of the ARB's Public Information Office at (916) 322- 2990.
Michael P. Kenny
1. Asbestos Fact Sheets
2. Local California Air District Phone List