IDUS is a coherent system proposed by Bill Hall. This is an acronym of the International Dozenal Unit System.

## Basic Design

IDUS begins defining the unit of time first. IDUS divided the day into twelve unciaDays or Dours (2 hours); unciaDays into grosan triciaDays or Parvas (42; seconds); triciaDays into grosan pentciaDays or Ticks (0;42 seconds) which are the base unit of time.

The unit of length, the Geck, originally meant to be length of an average human hand span is derived from the Tick and the speed of light. The speed of light is defined as 1 octqua Geck per Tick exactly (108Gk Tk-1) and thus, the length of a Geck is approximately 0.242 m (9½ inches) which is a little over the imperial span of 9 inches.

The unit of mass, called the Myd, which is derived from the conceptual definition "a cubic Geck of Water at its maximum density". This in turn defines the unit of density, called Spig (Specific Gravity).

The base unit for electrical units is impedance. This is unlike SI which uses current as its base unit. The unit of impedance is called the Heaviside which equals the impedance of free space (Z0). Due to speed of light being set to one (by a factor of twelve), the permittivity of free space (ε0) and the permeability of free space (µ0) equal one (by a factor of twelve).

The unit of temperature, the Ardor, originally meant to be a dozenal version of the Rankine Scale (absolute Fahrenheit scale) but with 350; Ad equal to the melting point of water at standard IDUS pressure.

The unit of amount of substance, the Berzel, is definied as the amount of substance that contains as many elementary particles as there are atoms in 10; Md of Carbon 10;. This sets the berzelar[note 1] mass constant = 1 Md / Bz compared to SI which defines the molar mass constant = 0.001 kg / mol.

## Standard Conditions

In physical sciences, standard conditions for temperature and pressure (informally abbreviated as STP) are standard sets of conditions for experimental measurements, to allow comparisons to be made between different sets of data. The most used standards are those of the International Union of Pure and Applied Chemistry (IUPAC).

The current version of IUPAC is the following:

• Temperature is set to 273.15 K (0 ºC)
• Pressure is set to 100 kPa (1 bar, 0.9869 atm)
• Molar Concentration is set to 1 mol dm-3 (which is the same as 0.001 mol m-3)

IDUS defines its standard conditions as the following:

• Temperature is set to 350; Ad (273.15 K, 0 ºC)
• Pressure is set to 154; Bo (101110 Pa, 1.0111 bar, 0.9979 atm)
• Berzelar[note 1] Concentration is set to 1 3Bz Ca-1

## Base Units

Unit Name Unit Symbol Quantity Conceptual Definition Standardization Definition SI Equivalent
Tick Tk Time pentciaDay 750 E58 389; periods of radiation corresponding to the transition between the two hyperfine levels of the ground state of Caesium E1; at absolute zero. 0.347 222 230 245 s
Geck Gk Length The length of an average human hand span The distance travelled in one octciaTick by the speed of light in a vacuum. c0 = 1 8Kn 0.242 090 783 970 m
Myd Md Mass A cubic Geck of water at its maximum density The reduce Planck constant is set to 7;E7EE20 29;Md Gk2 Tk-1 14.188 058 358 014 kg
Heaviside Hs Impedance The impedance of free space Z0 = μ0c0 = 1 376.730 313 461 771 Ω
Ardor Ad Temperature The melting point of water is equal to 350; Ad The Boltzmann constant is set to 7;442422 1E;Md Gk2 Tk-2 Ad-1 0.555 182 926 766 K
Berzel Bz Amount of Substance The amount of substance that contains as many elementary particles as there are atoms in 10; Md of Carbon 10;. 14 188.058 358 014 mol

## Derived Units

Unit Name Unit Symbol Quantity Derivation SI Equivalent
Sonif Sn Frequency Cycles / Tk 2.879 999 9335 Hz
Radian rad Angle Tau[note 2] rad / Circle 1 rad
Gradus (Supplementary Unit)  Angle 100; / Circle or 0;01 Tau[note 2] Radians 2.5º
Turns (Supplementary Unit)  T Angle 1T / Circle or Tau[note 2] Radians 360º (100;)
Steradian sr Solid Angle 2 Tau[note 2] sr / Sphere 1 sr
- - Area Gk2 0.058 607 9477 m2
Cask Ca Volume Gk3 14.188 444 001 5 dm3
Spig (or Specific Gravity) Sg Density Md / Gk3 999.972 819 889kg m-3 (Max Density of Water @ 357;20 Ad and 154; Bo)
Kine Kn Velocity/Speed Gk / Tk 0.672 214 417 m s-1
- - Acceleration Gk / Tk2 2.00 799 770 58 m s-2
Young Yu Energy/Work Md Gk2 / Tk2 6.897 066 847 J
Huygen Hy Force Yu / Gk 28.489 588 632 N
Boyle Bo Pressure Yu / Gk3 486.104 526 066 Pa
Povi Pv Power Yu / Tk 19.863 552 060 W
- - Momentum Hy Tk 9.892 218 504 N s
Kleve Kv Dynamic Viscosity Bo Tk 168.786 297 673 Pa s
Rhine Rh Kinematic Viscosity Gk2 / Tk

0.168 790 885 4 m2 s-1

168 790.885 4 cSt (cSt = mm2 s-1)

Zapp Zp Electric Current Pv0;6 / Hs0;6 0.229 621 829 6 A
Sargo Sa Electric Charge Zp / Tk 0.079 729 803 8 C
Devigi Dv Electric-motive Force / Potential Difference Yu / Sa 86.505 503 837 2 V
Kapa Kp Electric Capacitance Sa / Dv 921.673 191 239 5 μF
Nikola Nk Magnetic Flux Density Dv Tk / Gk2 0.149 212 542 3 T
- - Magnetic Flux Nk Gk2 0.008 746 040 9 Wb
Elduk Ed Inductance Tk2 / Nk 130.809 139 641 1 H
Villiard Vi Radioactivity Counts / Tk 2.879 999 933 5 Bq
Sorbi Sb Absorbed Dose Yu / Md

0.486 117 738 8 Gy

Egal Eg Equivalent Dose Yu / Md

0.486 117 738 8 Sv

## Other Accepted Units

Unit Name Unit Symbol Quantity Derivation SI/Imperial Equivalent
Dalton (Atomic Mass Unit) Da, u, amu Mass 0;1 x Mass of a C*10 Atom Same
Parva Pr Time 100; Tk ~50 s
Dour Dr Time 100; Pr or 10000; Tk ~2 hr
Day Dy Time 10; Dr 86 400.002 s
Neper Np Relative Power Level ln(x1) - ln(x2) 8.685 889 638 dN
Quad / Short League Quad Length 4Gk

5.019 994 496 km

0.903 526 811 leagues

## Approximation to Other Units

Unit Name   Unit Symbol  Quantity Derivation SI / Imperial Equivalent
Ton ton Mass 60; Md

1021.540 202 kg

1.005 41 Long Ton

Pound lb Mass 5 2Md 1.086 087 lb
Ounce oz Mass 3;6 3Md 1.013 681 oz
Stone st Mass 5;5 1Md 1.024 025 st
Grain gr Mass 1;3 5Md 1.099 915 gr
Kilogram kg Mass X 2Md 0.985 282 kg
Gram g Mass 1;6 4Md 1.026 335 g
Foot ft Length 1;3 Gk

0.302 613 479 962 m

0.992 826 379 ft

Inch in Length 1;3 1Gk 0.992 826 in
Yard yd Length 4 Gk 1.059 015 yd
Thou th Length 2;3 4Gk 1.034 194 th
Furlong fur Length 2Gk 1.039 760 fur
Mile mi Length 3Gk

1.673 331 499 km

1.039 759 mi

Kilometre km Length 2;6 3Gk 1.045 832 167 km
Imperial Gallon gal Volume 1Ca 1.040 340 gal
US Gallon gal (US) Volume 3;6 1Ca 1.093 222  gal (US)
Litre l Volume X; 2Ca 0.985 308 l
Imperial Pint pt Volume 2Ca 1.040 340 pt
US Pint pt (US) Volume 2Ca 1.041 164 pt (US)
Imperial Quart qt Volume 1Ca 1.040 340 qt
Imperial Fluid Ounce floz Volume 3;6 3Ca

0.971 953 floz

Acre acre Area 3;6 4Gk2 1.051 070 acre
Are a Area 1 3Gk2 1.012 745 a
Hectacre ha Area 8 4Gk2 0.972 236 ha

## Notes

1. Berzelar is used instead of Molar to keep reference to the unit for amount of substance, the Berzel.
2. Tau = 2 Pi ≈ 6;3494 (6.2832 decimal)