Dust originates from a variety of sources both inside and outside the home, composed of many microscopic particles.

Composition of Dust

Dust is made up of a mixture of particles including:

• Dead skin cells shed by humans and pets
• Clothing and carpet fibers
• Soil and garden particles
• Pollen and plant material
• Pet hair and dander
• Dust mites and their waste
• Microscopic bits of plastic and other synthetic fibers
• Soot, bacteria, and tiny insect parts

Sources of Dust

Outdoor sources (about two-thirds of household dust):

• Soil and garden dust tracked in on shoes, clothes, and pet fur
• Pollen carried in by wind and animals
• Road dust lifted by vehicles and wind
• Pollution particles from vehicle exhaust and industry
• Dust storms and natural events like bushfires that transport fine dust particles into homes

Indoor sources:

• Human and pet skin cells and hair continuously shed indoors
• Fibers from carpets, rugs, upholstery, and clothing
• Dust mites feeding on dead skin cells
• Cooking smoke, fireplace soot, and indoor pollution
• Decomposing insects and food particles

How Dust Enters Homes

Dust particles enter homes through:

• Open windows and doors
• Ventilation systems
• People and pets carrying particles on their bodies and clothing
• Being stirred up by daily activities like walking and pet movement

In summary, dust is a complex blend of organic and inorganic particles originating from both outdoor environments and indoor activities, constantly accumulating due to natural shedding and environmental infiltration.