The technical definitions for combustible dust vary. In Canada, the Hazardous Products Regulation (WHMIS 2015) defines combustible dust as  a mixture or substance that is in the form of finely divided solid particles that, upon ignition, is liable to catch fire or explode when dispersed in air.
Some rewards from employee incentive contests are exempt from income tax. Such rewards must be tangible personal property, for example, material goods that are for personal use and that are not deductable from the companyâs operating costs. Such rewards are not classified as income, but only up to the value of $1,600.
The law requires employers to withhold taxes from employee earnings to fund the Social Security and Medicare programs. These are called Federal Insurance Contributions Act (FICA) taxes. Your employer also pays a tax equal to the amount withheld from employee earnings. The self-employed pay Self-Employed Contributions Act (SECA) taxes on net earnings. SECA taxes also fund Social Security and Medicare. The self-employed pay both the employee and the employer share of SECA. But the law permits them to deduct half of the self-employment tax as a business expense.