Permissible exposure guidance level

An occupational exposure guideline (OEG), or permissible exposure guidance level... 

Permissible public exposure guidance levels (PPEGLs) for repeated accidental exposures of the public located or working near facilities using screening smokes in the open. 

These two definitions reflect two sides of the same situation. In this book, the term critical effect(s) will be used for the hazard/effect considered as being the essential one(s) for the purpose of the risk characterization, e.g., for the establishment of a health-based guidance value, permissible exposure level, or Reference Dose. It should be noted that the critical effect could be a local as well as a systemic effect. It should also be recognized that the critical effect for the establishment of a tolerable exposure level is not necessarily the most severe effect of the chemical substance. For example, although a substance may cause a serious effect such as liver necrosis, the critical effect for the establishment of, e.g., an occupational exposure limit could be a less serious effect such as respiratory tract irritation, because the irritation occurs at a lower exposure level. 

CFR1910.120(g)(3)(v) 29CFR1910.120, Appendix B 4.5.4 The level of protection provided by PPE selection shall be increased when additional information or emergency conditions show that increased protection is necessary to reduce employee exposures below permissible exposure limits and published exposure levels for hazardous substances and health hazards. (See Appendix B of 29CFR1910.120 for guidance on selecting PPE ensembles.)... 

The International Commission on Radiological Protection (ICRP) recommends specific limits of dose, applicable to stated time intervals (a quarter, a year, and so forth) as guidance for protection of radiation workers these are called maximum permissible doses and are applicable to individuals exposed continuously or intermittently from time to time as their work requires (40). To assist the planning of nuclear designs and operations so as to minimize, appropriately, the low level exposure of members of the public which may ordinarily result from normal operations, dose limits for individual members of the public are recommended by ICRP which are one-tenth or less of the maximum permissible doses for radiation workers. Though these maximum permissible doses and dose limits have little to do directly with the control of major radiation emergencies (i.e., reactor accidents) they are quoted in brief in Table VII. 

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