Yes, it is safe. Nosk is certified by the FDA in America, CE in Europe and Kitech (Korea Institute of Industrial Technology).

However, if you have recently undergone any nasal/nose surgery or suffered from any condition related to the nose, nasal cavity or sinuses including but not limited to; sores, lesions, bleeding, infections, swelling, facial pain/pressure, discharge, fever, and or any sleeping or breathing disorders such as sleep apnea- then it recommended that you consult a physician before using Nosk.

No, the filter is not replaceable. Nosk has to be discarded once its life is over.

NOSK is not generally recommended for use for over 12 consecutive hours.

Reuse of Nosk is not recommended without rinsing the filter gently in clean water.

NOSK is designed with your comfort in mind, however if you experience any discomfort in breathing or otherwise, then remove Nosk immediately and discontinue future use.

As per independent tests done in lab, the efficiency of Nosk in filtering the particulate matter is upto —

PM 10 — 100%
PM 2.5 — 96.3%
PM 1     — 96.1%

Nosk is designed to only block the harmful pm 10/pm 2.5/pm 1 particles. It cannot modify your sense of smell since it does not contain odour neutralising chemicals. This is a chemical free product and hence it is suitable for a wider range of users.

NO. Nosk cannot be used while sleeping.

Yes, it’s washable and ideally it should always be washed after using it.

It must be washed under gentle flow of tap water. Also, do not use soap/detergent to wash it.

This is a not easy to define- It is similar to asking – “How many hours will someone’s white shirt will get dirty in when one is outside?”
Life of Nosk nose mask depends on levels of pollution which is quite difficult to measure as one moves constantly indoors/outdoors and pollution levels vary with time also. If you stand next to a construction site/bonfire which is a high pollution site- so Nosk’s life may be seriously impacted. But in medium pollution it may last more.