Tech: FIT™

How FIT™ is your showerhead

The FIT™ value (Flow Impact Density) has been developed as a means of measuring the strength of flow stream generated by a showerhead. When this figure is divided by the water volume consumed an overall performance value for the showerhead is arrived at.
The Flow Strength of a showerhead can be determined by a physical measure of the power that it generates, when tested on a modified *Hookian-Young’s Modulus Spring Scale System. The FIT value measured on the system is then divided by the actual amount of water used to generate the FIT measurement, with the result being the showerhead’s overall performance value relative to the amount of water that it has consumed during the test procedure. The higher the number, the better the performance (P) of the showerhead. Obviously, some showerheads will perform better than others due to the overall efficiency of their design and inherent flow strength capabilities.
Showerheads lacking in a High Flow Impact (FIT™) value must use a much higher flow volume delivery (VR), in order to compensate for the lack of power. When this happens the showerhead’s overall performance value (P) falls off dramatically. This can be readily calculated using the formulae shown below, where:

Performance Value Rating (P) of Low-Flow Showerheads Tested
	Product Tested	Flow Rate (VR) L/Min	*FIT™ Value (dynes x 10³)	PERFORMANCE VALUE
BrightWater Products	BrightWater Chrome Fixed	4.75	8.36	6.67
	BrightWater Elite Chrome Fixed	5.66	9.86	6.61
	BrightWater Hand Held Chrome	5.67	9.69	6.47
	Delta 1.6	5.9	7.11	4.57
	Turbine, Sunbeam	5.98	7.01	4.44
	Oxygenics	6.19	7.42	4.55
BrightWater Products	BRICOR Pre-Rinse Sprayer	2.26	16.43	27.49

*FIT Measurement

BrightWater’s Showerheads are measured with the patented Vacuum Flow™ Valve and must pull a minimum vacuum strength of -19.6 inches Hg across the air intake orifice for maximum operating efficiency. Under these conditions, for example, the BrightWater Elite fixed Showerhead will produce a flow strength value of 9.86 x 10³ Dynes (6.90 g-cm/sec²) at 5.2 l/min when measured on a modified Hookean/Young’s Modulus Spring System, attached to a 1 foot diameter circular aluminum shield plate, held 8 inches distance from the flow volume emission point coming out of the showerhead spray plate.

In these conditions the BrightWater showerhead at 5.2 l/min is producing a FIT™ measurement 1.75 times stronger than a conventional low flow showerhead running at a flow of 9.47 l/min., by direct comparison, and measured on the same Hookean/Young’s Tension Spring Plate Apparatus. Reference: Handbook of Chemistry and Physics, 24th Edition, Pages 2219, 2216-2217 & Table 1661.