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=== Presenting results of chemical analysis without comparison to exposure levels that may cause harm, or legal limits for workplace exposure. === | === Presenting results of chemical analysis without comparison to exposure levels that may cause harm, or legal limits for workplace exposure. === | ||
Analytical techniques such as Gas Chromatography/Mass Spectroscopy can detect tiny quantities of compounds in a sample, Limits Of Detection are becoming lower as electronics and computing increase in power and efficiency. Equipment manufacturers compete with each other to detect tinier, and tinier levels. This is a good thing for the most part, as anything that is present no matter how tiny the amount will be detected. | Analytical techniques such as Gas Chromatography/Mass Spectroscopy can detect tiny quantities of compounds in a sample, Limits Of Detection are becoming lower as electronics and computing increase in power and efficiency. Equipment manufacturers compete with each other to detect tinier, and tinier levels. This is a good thing for the most part, as anything that is present no matter how tiny the amount will be detected. However this can be a problem too. | ||
They focus more on the fact that nanoscopic quantities where discovered, and completely forget to compare the amounts with something sensible (like permitted workplace exposure limits) presumably because their data would be 'lost in the weeds' in comparison. | |||
It is also not good practice to operate equipment at or near it's LOD (Limit Of Detection), if a percentage of samples that can be expected to contain some trace of e.g. Nicotine result in no detection, then it is safe to assume, the instrument is operating at the extreme of it's capability. Most of the time, manufactures and good practice, suggest avoiding the extreme ends of the range, due to issues such as noise at the low end, and detector swamping at the high end. An example more commonly encountered; an audio amplifier will sound best when operated somewhere in the middle of it's power output range. (Too low, and noise can be apparent, too high, and distortion becomes a problem) Scientific equipment is not so very different, it uses electronics, and the laws of physics still apply. | |||
=== Unusual or confusing definitions === | === Unusual or confusing definitions === | ||
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