Space heaters provide clean, efficient heat for all types of outdoor, indoor, and construction applications where a permanent heat source is not available or has been temporarily interrupted. Kerosene and LP-fired models may be exactly what you need for a garage, outbuilding, or large workshop - places a small electric heater just doesn’t have the ability to warm up. In fact, these models deliver between two and five times the heat of a small electric model.
And while these heaters are best suited to well-ventilated areas, they can also be used in tight, well-insulated places as long as some safety precautions are taken. Those include opening a window a bit in the room and using a carbon-monoxide detector near the heater. And of course, always follow the instructions in your operator’s manual.

How do you choose a space heater that's right for your needs?
The output of a heater is measured in Btu, an acronym for “British Thermal Unit.” One Btu is approximately equal to the heat generated from one matchstick. Actually, the more accurate definition is “the quantity of heat required to raise the temperature of one pound of water by one degree on the Fahrenheit scale.”
Many factors come to play in choosing a space heater. You will need to know how big the area is you want to heat and how much you want to raise the temperature in that area. Multiply those figures together. Then, to determine what size space heater you need, multiply that total by 0.133 to calculate the minimum Btu's needed to heat the area.

For quick reference, use these simple guidelines:
Smaller heating applications that require 60,000 Btu or less include; ventilated one- and two-car garages; do-it-yourself projects; small construction sites; remodeling; outdoor events; workshops; and light commercial applications.
Medium to large heating applications that require 70,000 Btu or more include; medium to large construction sites; concrete freeze protection; agricultural use; greenhouses; loading docks; industrial and commercial sites; highway construction; and various sporting events.
Note: Based on a 10-foot ceiling, all applications require ventilation of 3 square feet of fresh outside air for each 100,000 Btu/hour of heater rating.