Hardener
Hardener/Accelerator, used with a two pack epoxy/polyurethane coating systems. Also wood repair systems and adhesives. 
Hod
Hod used for transporting bricks or mortar.
Hod Carrier a labour who physically carries bricks or mortar.
Hydrochloric Acid
Hydrochloric Acid Acid is used to etch newly laid cementitious before painting.
It is also available to remove unwanted mortar splashes from bricks.
Hydrochloric acid and can also be applied 
as a rust remover.
See Phosphoric Acid.
It is inportantant that the all H&S and Product details are followed as stated on the manufactures data sheets before use.
Knot Brush
Brush, round or oval in shape, i
n either one or two knots used for applying distempers and limewash or for washing down.
Knotting
A shellac based on Methylated Spirit for use over resinous to prevent tannic bleeding from knots and sap residue within hardwoods.
Leafing/Flake Aluminium Primer
Aluminium primer for hardwoods and for sealing against tannic acid- resin residue and bitumen.
Litmus Paper
Litmus Paper
The main use of litmus is to test whether a wetted surface or solution is acidic, as blue litmus paper turns red and red litmus paper turns blue when alkaline is present.
Monochromatic Colour Scheme
A monochromatic color scheme is a colour palette that uses a single colour being variations of that hue.
The base color's saturation and brightness are adjusted to create different shades.
White and black are usually included as the two extremes of the color spectrum.