Air quality within and around structures can be affected by gasses, particulates, or microbial contaminants. These can include mold, carbon monoxide, asbestos, and radon. Orange County Environmental Health does not regulate indoor air.  

However, we wish to provide you with information and tips to assist you. The information below has been gathered from other governmental agencies and/or reputable news sources and is believed to be accurate at this time. 

Mold/Asbestos Resources

• What about mold?
• General information about mold
• Mold in your home
  • Housing standards: mold
• Mold in the workplace
• EPA Guidance on residential mold cleanup
• Department of Labor Guide to mold in the workplace
• EPA information on asbestos
• CDC information on asbestos safety in the workplace
• CDPH Asbestos Info Sheet
• Accredited Laboratories for Asbestos Fiber Analysis
• Landlord / tenant handbook

For additional Indoor Air Quality resources, please visit:

• CDPH Indoor Air Quality Program
• EPA Indoor Air Quality

Useful phone numbers:

• Fair Housing (landlord / tenant issues): (714) 569-0823
• Legal Aid Society of Orange County: (714) 571-5200

Fraudulent Notification Sign We have received reports of “Do Not Enter” signs posted at properties in Orange County. The sign has our logo and contact information. Currently, Environmental Health Housing does not post “Do Not Enter” signs. We are working to identify and contain the source(s) of these signs. If you have any questions or information, please contact us immediately. (714) 433-6000 and/or ehealth@ochca.com