Module 5

Indoor Plant Air Purification Guide

NASA-studied plants that clean indoor air, with child/pet safety ratings

NASA's Clean Air Study found certain houseplants remove formaldehyde, benzene, and other VOCs. Aim for 1 plant per 100 sq ft for measurable effect.

Plant	Removes	Difficulty	Safe for Kids/Pets?
Spider Plant	Formaldehyde, xylene, carbon monoxide	Easy — tolerates neglect	Yes — non-toxic
Boston Fern	Formaldehyde, xylene	Moderate — needs humidity	Yes — non-toxic
Bamboo Palm	Formaldehyde, benzene, trichloroethylene	Moderate — bright indirect light	Yes — non-toxic
Rubber Plant	Formaldehyde, carbon monoxide	Easy — low light tolerant	No — toxic sap if ingested
Peace Lily	Benzene, formaldehyde, ammonia, trichloroethylene	Easy — low light, droops when thirsty	No — mildly toxic (calcium oxalate)
Areca Palm	Formaldehyde, xylene, toluene	Moderate — bright indirect light	Yes — non-toxic
Snake Plant	Formaldehyde, benzene, nitrogen oxides	Very easy — nearly indestructible	Mildly toxic if ingested — keep out of reach
Pothos (Golden)	Formaldehyde, benzene, carbon monoxide	Very easy — any light condition	No — toxic if ingested. Hang high.
Chinese Evergreen	Formaldehyde, benzene	Easy — low light tolerant	No — toxic (calcium oxalate crystals)
Gerbera Daisy	Benzene, trichloroethylene, formaldehyde	Moderate — needs direct sun	Yes — non-toxic

Important

Overwatered houseplants are a mold source. Use pots with drainage holes, avoid saucers with standing water, and let soil dry between waterings. If you see white fuzz on soil, scrape it off and reduce watering. Terra cotta pots are better than plastic for airflow.

For homes with toddlers, stick to the non-toxic options: Spider Plant, Boston Fern, Bamboo Palm, Areca Palm, and Gerbera Daisy. Place all plants on high shelves or in hanging planters out of reach regardless.