Preventing electrocutions, always keep portable an electric space heater away from water. If must take it and use it to an appliance near water always use a ground fault circuit interrupter! And please you don’t forget also to never use space heaters in a bathroom or near a sink.

For exact information, we can check to the manufacturer’s instructions to see how far the heater should be placed from combustible materials, and for how far the heater should be place from the floor so that carpeting or flooring materials don’t ignite. Although electric space heater doesn’t have an open flame, the heating elements of some types of electric heaters are hot enough to ignite nearby combustibles like draperies, paper, clothing, furniture, and flammable liquids. Therefore, important to check surrounding objects periodically to see condition that they feel hot or not.

Here they are the safety rules for use space heater:

• Keeps the heater in safe working condition Replace missing guards and controls at once!
• For more safety reason, please never operate a defective heater.
• Do not use an electric heater as a dryer by placing clothing over it and never use it heater to thaw pipes.
• Regardless of the type of heating system you have, install and maintain at least one smoke detector that is in good working condition on each floor of your home.
• Place the heater on a level surface for stability keep out from the water.
• Don’t place the heater where children might play near it or where people might trip over or bump into it.

Recommends selecting an electric space heater are below:

• Portable electric heaters that heat by circulating oil or water, however, usually have lower surface temperatures and may not need guards. Therefore recommend to you to buy a heater with a guard around the heating element. A wire grill or other protection is essential to keep fingers or fabrics from touching the hot element.
• Look for one that is listed with a nationally-recognized testing laboratory. These heaters have been tested to meet specific safety standards, and manufacturers are required to provide important use and care information to the consumer. On heaters that are not listed, consumers have less assurance that the safety features and operating instructions are adequate.
• Please always keep portable electric heaters away from water and never touch an electric heater if you are wet. It for preventing electrical shocks and electrocutions, before using the heater, read and follow the instructions for its operation and maintenance.
• A portable electric space heater is designed for use only as temporary supplemental heating and only while attended. So wisely do not leave the heater operating while sleeping or operating unattended.
• If you must use an extension cord, make sure it is a heavy duty cord marked with a # 14 gauge or larger wire An incorrectly-sized cord may create a fire hazard. If the heater’s plug has a grounding prong, use only a grounding (three-wire) extension cord. Please never run the heater’s cord (or any cord) under carpeting or rugs!

Source: Consumer Product Safety Commission (CPSC)