Scientific laws are considered established and universally applicable (to certain class of things or phenomenon under appropriate conditions) but not necessarily definitive. Also called laws of science.
Afflictions of the respiratory system include irritation and infection of the ears, nose and throat. Respiratory problems also may involve congestion, which can be decreased by inhaling rosemary (especially the verbenone type), hyssop (use var. decumbens only), tea tree, eucalyptus, lavender or peppermint.
Many people want to diffuse essential oils to induce and improve sleep or the help clear sinuses and the respiratory track during the night so this restriction is a considerable drawback of candles in these circumstances.