Nonionizing radiation defined

Define nonionizing radiation and provide several examples generating devices. 

The commercial nonionic surfactants do not absorb radiation in the visible spectrum. The simplest form of spectrophotometric analysis of nonionics is the direct measurement of the UV absorbance of the sample. The ethoxylated alkylphenols are the only compounds which can be readily determined by this method, with a maximal absorbance at about 223 nm and another peak at 276 nm (69). Ethoxylated amides may be determined in model systems by their absorption of light at 202 nm (70), but many other compounds found in typical samples also have absorbance in this region. Because of the sensitivity of direct UV analysis to interference, it can only be used in well-defined situations. Interferences often encountered in nonionic surfactants are oxidation inhibitors like butylated hydroxytoluene. 

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