Hoʻolālā ʻia ka ʻōnaehana hoʻāʻo mamao mamao no nā kaʻa ʻaila a me nā kaʻa diesel, a hiki ke ʻike i ka opacity, particulate matter (PM2.5), a me ka amonia (NH3) o nā kaʻa a me nā kaʻa diesel.
ʻO ka ʻōnaehana hoʻāʻo mamao mamao kū i kahi kumu kukui a me kahi ʻāpana kānana, kahi ʻāpana noʻonoʻo hoʻoneʻe ʻākau ʻākau, ʻōnaehana loaʻa wikiwiki/wikiwiki, kahi ʻōnaehana ʻike kaʻa, kahi ʻōnaehana hoʻouna ʻikepili, kahi ʻōnaehana wela mau, kahi ʻōnaehana meteorological a me kahi. ʻāpana hana, hiki ke hoʻokele mamao ʻia ma o ka pūnaewele.