The primary industrial use of boric acid is in the manufacture of monofilament fiberglass usually referred to as textile fiberglass. Textile fiberglass is used to reinforce plastics in applications that range from boats, to industrial piping to computer circuit boards.
Boric Acid is used as a Nuclear Poison in modern PWR type Nuclear Reactors as it Reduce Fission Process by Reducing Neutrons Flux. It is used in PWR Nuclear Reactor's Coolant water for Controlling Reactor Power as well as to Perform Emergency Reactor Shutdown.
In the jewelry industry, boric acid is often used in combination with denatured alcohol to reduce surface oxidation and thus formation of firescale on metals during annealing and soldering operations.
Boric acid is used in the production of the glass in LCD flat panel displays.
In electroplating, boric acid is used as part of some proprietary formulas. One such known formula calls for about a 1 to 10 ratio of  to nickel(II) sulfate|, a very small portion of sodium lauryl sulfate and a small portion of sulfuric acid|.
The solution of orthoboric acid and borax in 4:5 ratio is used as a fire retarding agent of wood by impregnation.
It is also used in the manufacturing of ramming mass, a fine silica-containing powder used for producing induction furnace linings and ceramics.
Boric acid is added to borax for use as welding flux by blacksmiths.
Boric acid, in combination with polyvinyl alcohol (PVA) or silicone oil, is used to manufacture Silly Putty.
Boric acid is also present in the list of chemical additives used for hydraulic fracturing (fracking) in the Marcellus Shale in Pennsylvania. It is often used in conjunction with guar gum as cross-linking and gelling agent for controlling the viscosity and the rheology of the fracking fluid injected at high pressure in the well. It is important to control the fluid viscosity for keeping in suspension on long transport distances the grains of the propping agents aimed at maintaining the cracks in the shales sufficiently open to facilitate the gas extraction after the hydraulic pressure is relieved. The rheological properties of borate cross-linked guar gum hydrogel mainly depend on the pH value.
Boric acid is used in some expulsion-type electrical fuses as a de-ionization/extinguishing agent. During an electrical fault in an expulsion-type fuse, a plasma arc is generated by the disintegration and rapid spring-loaded separation of the fusible element, which is typically a specialized metal rod that passes through a compressed mass of boric acid within the fuse assembly. The high-temperature plasma causes the boric acid to rapidly decompose into water vapor and boric anhydride, and in-turn, the vaporization products de-ionize the plasma, helping to interrupt the electrical fault.