Stone and Tile Blog: Does Terrazzo Contain Asbestos and is it dangerous to restore or maintain?

Does Terrazzo Contain Asbestos and is it dangerous to restore or maintain?

By Frederick M. Hueston, Stone Forensics

There are millions of square feet of terrazzo floors throughout the US and the world. I have had several calls in recent year from terrazzo refinishing contractors that are concerned with asbestos exposure when working with terrazzo. The following explains the dangers as well as how to safely restore and maintain terrazzo

Asbestos Exposure

First lets take a look at what asbestos is and how one becomes exposed.

When asbestos fibers as small as a human hair become airborne, asbestos exposure occurs. The hazardous mineral dust can linger in the air for hours, posing a risk to anyone nearby who breathes it in or consumes it.

Asbestos fibers may take 48 to 72 hours to settle in a setting with few disturbances. The dust is so light that if it is disturbed, it can readily become airborne once more.

Asbestos exposure in Terrazzo

Terrazzo that was poured before the 1980’s may contain asbestos and for this reason it is recommended that it be tested for asbestos before any abrasives are used on it. Even though the abrasives are used wet it can still produce asbestos fibers in the air. It is still possible to grind and hone asbestos containing terrazzo but will require the services of an asbestos abatement company. This will involve workers wearing fully equipped hazmat suits and will also require the area to be sealed off as well as the use of HEPA filter vacuums etc.

Maintenance of Asbestos Containing Terrazzo

Maintaining a terrazzo floor that contains asbestos is another story and as long as no abrasives are used, maintenance is simple and won’t expose you or anyone to these harmful fibers. If a floor finish is used it serves to contain the asbestos, however the current trend in terrazzo refinishing is to place a highly reflective shine on the floor though diamond abrasives. If this is the case than asbestos abatement practices will be necessary. Once the terrazzo is polished or a coating is placed on it the following maintenance program will be applicable:

Daily Maintenance

The three most important tasks that can be done on a daily basis to keep the terrazzo looking new and extending the time before restoration is required are: Dust Mop, Dust Mop and Dust Mop. The most destructive material to most terrazzo is sand, dirt and miscellaneous grit. If these substances could be eliminated, maintenance of the terrazzo would be almost non-existent. A terrazzo floor can never be dust mopped too often. Use a clean, non-treated, dry dust mop at least two to three times a day in high traffic areas and less often in low traffic areas. Walk off mats placed outside and inside an entrance will also eliminate a good portion of sand, dirt and grit. It takes approximately seven steps to remove all loose dirt from the bottom of ones shoes. Walk off mats also need to be removed and cleaned daily. Keep this in mind when purchasing walk off mats. Remember if sand, dirt and grit are eliminated there will be nothing left behind to scratch and dull the terrazzo. This will also keep any abrasive grit from releasing asbestos into the air.

Cleaning

All terrazzo, both polished and unpolished should be cleaned daily in high traffic areas and less often in lower traffic areas. A clean rayon or cotton string mop should be used with cold to warm water with the addition of a quality Green Approved neutral cleaner or stone soap. Approved Green Neutral cleaners are defined as surfactant type detergents that have a Ph of 7. Acidic and alkaline cleaners should not be used. Be sure to follow the directions very carefully.

If the area is large an auto scrubber can also be used with the same neutral cleaner and a soft brush or pad.

Maintaining Terrazzo that contains asbestos is simple and top rule to follow is to avoid any abrasives.

Frederick M. Hueston

Stone Forensics

E-Mail: Fhueston@stoneforensics.com

Web Site: www.stoneforensics.com

References

https://ehss.syr.edu/wp-content/uploads/2016/12/GD-14-Common-Asbestos-Containing-Materials-from-CR56.pdf

https://www.asbestos.qld.gov.au/sites/default/files/asbestos-flooring.pdf?v=1553738546

https://www.colorado.edu/ehs/sites/default/files/attached-files/cu_asbestos_om_program_.pdf

https://facilities.uw.edu/partner-resources/files/media/asbestos-om.pdf

https://afd.calpoly.edu/ehs/docs/asbc_97a.pdf