Don't run an engine in a garage or anywhere else without proper ventilation - EVER! Carbon monoxide is poisonous. It takes a long time to leave the body and can build up a deadly supply of it in your system by simply breathing in a little every day. You may not realize you are slowly poisoning yourself. Always use power vents, windows, fans or open the garage doors.Don't work around moving parts while wearing a necktie or other loose clothing. Short sleeves are much safer than long, loose sleeves and hard-toed shoes with neoprene soles protect your toes and give a better grip on slippery surfaces. Jewelry such as watches, fancy belt buckles, beads or body adornment or any kind is not safe working around a vehicle. Long hair should be tied back or hidden under a hat.Don't use pockets for tool boxes. A fall or bump can drive a screwdriver deep into your body. Even a wiping cloth hanging from the back pocket can wrap around a spinning shaft or fan.Don't smoke when working around gasoline, cleaning solvent or other flammable material.Don't smoke when working around the battery. When the battery is being charged, it gives off explosive hydrogen gas.Don't use gasoline to wash your hands. There are excellent soaps available. Gasoline may contain lead, and lead can enter the body through a cut, accumulating in the body until you are very ill. Gasoline also removes all the natural oils from the skin so that bone dry hands will suck up oil and grease.Don't attempt to service the air conditioning system unless you are equipped with the necessary tools and training. In most states it is now illegal to discharge refrigerant into the atmosphere due to the harmful effects Freon (R-12) has on the ozone layer. Most states now require that an approved recovery system be used to consume the discharged Freon and that the operator be licensed to operate the equipment.