Â· 43 comments. in Facts. An intelligence quotient, or IQ, is a score derived from one of several standardized tests designed to assess intelligence. The abbreviation âIQâ comes from the German term Intelligenz-Quotient, originally coined by psychologist William Stern.
Lower explosive limit. Lower explosive limit (LEL): The lowest concentration (percentage) of a gas or a vapor in air capable of producing a flash of fire in presence of an ignition source (arc, flame, heat). The term is considered by many safety professionals to be the same as the lower flammable limit (LFL).
Light Emitting Ceramic (LEC) grow light - LEC is a brand name (trademark) for a model of grow light that uses ceramic metal halide technology. However, the term LEC is starting to become interchangeable with the term Ceramic Metal Halide (CMH) since they're both referring to the same technology.