Sawdust

Sawdust (or wood dust) is a by-product or waste product of woodworking operations such as sawing, sanding, milling and routing.

Two waste products, dust and chips, form at the working surface during woodworking operations such as sawing, milling and sanding.

Sawdust has a variety of other practical uses, including serving as a mulch, as an alternative to clay cat litter, or as a fuel.

The claim for invention of the first commercial charcoal briquettes goes to Henry Ford who created them from the wood scraps and sawdust produced by his automobile factory.

[3] Cellulose, fibre starch that is indigestible to humans, and a filler in some low calorie foods, can be and is made from sawdust, as well as from other plant sources.

All these organisations recognize wood dust as carcinogenic in relation to the nasal cavities and paranasal sinuses.

There is an equally detrimental effect on beneficial bacteria, so it is not at all advisable to use sawdust within home aquariums, as was once done by hobbyists seeking to save some expense on activated carbon.

[citation needed] Questions about the science behind the determination of sawdust being an environmental hazard remain for sawmill operators (though this is mainly with finer particles), who compare wood residuals to dead trees in a forest.

Technical advisors have reviewed some of the environmental studies, but say most lack standardized methodology or evidence of a direct impact on wildlife.

[citation needed] Other scientists have a different view, saying the "dilution is the solution to pollution" argument is no longer accepted in environmental science.

[citation needed] Of larger concern are substances such as lignins and fatty acids that protect trees from predators while they are alive, but can leach into water and poison wildlife.

[citation needed] Wood flour is commonly used as a filler in thermosetting resins such as bakelite, and in linoleum floor coverings.

[18] Wood flour has found a use in plugging small through-wall holes in leaking main condenser (heat exchanger) tubes at electrical power generating stations via injecting small quantities of the wood flour into the cooling water supply lines.

Some of the injected wood flour clogs the small holes while the remainder exits the station in a relatively environmentally benign fashion.

[citation needed] Large quantities of wood flour are frequently to be found in the waste from woodworking and furniture companies.

[citation needed] Wood flour can be subject to dust explosions if not cared for and disposed of properly.

[citation needed] As with all airborne particulates, wood dust particle sizes are classified with regard to effect on the human respiratory system.

[22] Dust emitted in the wood industry is characterized by the dimensional disintegration of particles up to 5 μm, and that is why they precipitate mostly in the nasal cavity, increasing the risk of cancer of the upper respiratory tract.

It has been demonstrated through human epidemiologic studies that exposure to wood dust increases the occurrence of cancer of the nose (nasal cavities and paranasal sinuses).

The hood is designed to provide high capture velocities, often greater than 50 m/s (10,000 fpm) at the contaminant release point.