Photons may occur in the form of x-rays, gamma rays, or quanta of light. The energy (E) of a photon is expressed as the product of its frequency (v) and Planck's constant (h), as in the equation E = hv. X-ray photons occur in frequencies of 10 18 to 10 21 Hz and energies that range upward from 1 KeV.
Confidence votes 52.5K. In the US, the standards called General Industry Standards are the OSHA standards at 29 CFR 1910 and are sometimes called Part 1910.
Search by SIC Code. The Standard Industrial Classification (SIC) code system is used to classify a firm's primary industry. Search by Industry. An industry is the primary business activity of any firm. Industries are determined by common products, services, production and delivery system of businesses.