A nice sharp 2 tone blue flame is ideal. A little orange at the tips is nothing to worry about. If you have much more yellow or orange than that your fuel/air mixture is incorrect.
The DeLonghi DFH255OTB Safe Heat Fan Heater is a safe option
You need to get a specified bathroom heater for it to be considered safe.
The Mr. Heater Propane Garage Heater is a very safe model
Non luminous zone is the zone of a flame which is also the hottest zone of the flame as it is mostly in contact with oxygen. It is also called invisible zone.
It is safe to have a space heater, but it does have risks like anything else. If someone wants to use a space heater, they should be very careful.
wat if i knock down a kerosene heater
you make sure that the nosel is covered otherwise it wont be a safe flame
because the hole is closed, less oxygen is getting to the flame and therefore the flame cools down and is safe.
The direct air heater takes the space air or fresh air and mixes it with hot gasses from a flame source such as natural gas flame or oil fired flame and returns / redirects it to the space to be heated. The warm air contains all the flame byproducts and toxic gasses along with. This type of air handling system is used in industrial environment where the human beings are not exposed to such warm air. In the indirect system the hot flame gasses circulate through a metallic high efficiency heat exchanger which isolates the flame gasses (aka flue gasses) from that of the air to be warmed by passing from the other side of the heat exchanger. This type of air is safe for human exposure as the flame products and toxic COx, NOx and SOx are isolated. usually all the domestic air heaters are of indirect type.
To set up a campsite that is safe from fire, you should surround the open flame with a nonflammable material such as rocks. In addition, never leave the flame unattended.
At least 1 foot.
They are if they are monitored and unplugged after use.