Skip to main content Skip to site navigation

What We Do and Don’t Accept

General information

The HHW Collection Facility is open to San Mateo County residents.  Residents must make an appointment for drop off due to participation limits at each location. There is a limit of 10 gallons or 50 pounds per appointment based on transportation regulations. 

NOTE: Empty containers are not hazardous waste and may be disposed of in the garbage—just leave the lids off so your waste hauler can see that the container is empty and non-hazardous.

The HHW Program accepts the following wastes:


Aerosol cans (spray paints, hair spray, and other aerosol sprays EXCEPT food grade products like cooking oil sprays)


Art and hobby supplies (photo chemicals, glues)


Automotive supplies (car batteries, motor oil, antifreeze, brake fluid, gasoline, fuel additives chrome polish, many waxes)

Free convenient drop off locations also exist for the following automotive supplies:

Batteries (all household types)

Many retailers of these products also take them back for free at their store locations. Curbside pickup for household batteries may be provided by your local solid waste management company.

Cosmetics (nail polish, nail polish remover, perfumes, etc.)


Fluorescent lights (all sizes and types)

Free convenient drop off locations also exist for fluorescent lights.
Fire extinguishers Residential fire extinguishers are typically dry chemical (sodium bicarbonate or monoammonium phosphate) and carbon dioxide, and are not hazardous.  These may be discharged into the regular trash. However, monoammonium phosphate is an irritant to the respiratory tract and to eyes. So, discharge the unit outside, away from kids or pets, wear goggles and a particulate mask. Then recycle the emptied unit as a plastic or metal container. If you don’t feel comfortable doing that, bring them into the HHW Program.
Garden fertilizers, herbicides and pesticides  
Household cleaning chemicals (bleach, stain removers, all-purpose cleaners, polishes)  
Mercury-containing thermometers and thermostats See Thermostat Recycle Corporation for list of free convenient drop off locations.
Painting supplies and Home Improvement (Paint, spray paint, stains, thinners, varnish, epoxy, fiberglass, roof tar, etc.) Many paint stores now take back paint, stain, and varnish year‐round for free during their regular business hours as part of the PaintCare program.  Find locations at
Poisons (powders, sprays, baits, pest killing products)  
Pool or spa chemicals  
Propane tanks and outdoor cooking fluids (lighter fluid, camp stove fuel, tanks for gas grills), maximum 5-gallon size

Take advantage of propane cylinder exchanges, such as Blue Rhino, Amerigas, and Pick-Up Propane.

If empty: compressed gas cylinders are exempt from California regulation when they are empty. Remove the valve or otherwise create a hole in the tank to ensure it is at atmospheric pressure and dispose with solid waste. Contact local metal recyclers for possible recycling.

The HHW Program does not accept the following wastes:


Ammunition, explosives, fireworks, gun powder

 Contact local law enforcement


Find local disposal locations



Contact the following Bay Area landfills:

Construction and demolition debris

Find local disposal locations
Cooking oil Find local disposal locations
Electronic waste Find local disposal locations
Helium tanks (party balloon tanks) Contact the manufacturer for disposal instructions
Compressed gases (except propane for camping stoves or barbecues) If empty:compressed gas cylinders are exempt from California regulation when they are empty. Remove the valve or otherwise create a hole in the tank to ensure it is at atmospheric pressure, and dispose in with solid waste. Contact local metal recyclers for possible recycling.
Medical, biohazard, infectious wastes Contact the San Mateo County Medical Waste Program
Pharmaceuticals, prescription medications, over-the-counter drugs Many local police stations will take them back. 
Pressure-treated wood


List of approved landfills that accept treated wood waste

Further information

Sharps, lancets, needles

 Find local disposal locations

Smoke detectors Call the manufacturer for mail-back recycling; or call First Alert at 1-800-323-9005
Styrofoam Find locations for disposal at Recycleworks
Tires Find local disposal locations
Business waste See if you quality for the Very Small Quantity Generator (Business) Program
Contact a Registered Hazardous Waste Transporter

Contact us directly at 655-6217 or if you have questions.