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→Dose Limits
|+<center> <span style="color:#4682B4; font-size: 110%;"> '''Dose Limits Recommended by ICRP''' </span> </center>
! style="width: 30%;" | Type of Dose Limit
! style="width: 30%;" | Limit on Dose from [[System_of_radiation_protection_module_2#Exposure Categories and Situations | Occupational Exposure]]! style="width: 30%;" | Limit on Dose from [[System_of_radiation_protection_module_2#Exposure Categories and Situations | Public Exposure]]
|-
|[[Absorbed, Equivalent, and System_of_radiation_protection_module_2#Effective Dose | Effective Dose]]
|20 mSv per year, averaged over defined periods of 5 years, with no single year exceeding 50 mSv <br /> <span style= "font-size:70%;"> After a worker declares a pregnancy, the dose to the embryo/fetus should not exceed about 1 mSv during the remainder of the pregnancy </span>
|1 mSv in a year <br /> <span style= "font-size:70%;"> In special circumstances, a higher value could be allowed in a single year, provided that the average over 5 years does not exceed 1 mSv per year </span>
|-
|[[Absorbed, Equivalent, and System_of_radiation_protection_module_2#Effective Dose|Equivalent Dose]] to the Lens of the Eye
|20 mSv per year, averaged over defined periods of 5 years, with no single year exceeding 50 mSv <br />
|15 mSv in a year
|-
|[[Absorbed, System_of_radiation_protection_module_2#Equivalent, and Effective Dose|Equivalent Dose]] to the Skin <br /> <span style= "font-size:70%;"> Averaged over 1 cm<sup>2</sup> of skin regardless of the area exposed </span>
|500 mSv in a year
|50 mSv in a year
|-
|[[Absorbed, System_of_radiation_protection_module_2#Equivalent, and Effective Dose|Equivalent Dose]] to the Hands and Feet
|500 mSv in a year
| -
|}
Dose limits alone are not enough to ensure adequate protection. They function in combination with the [[System_Of_Radiation_Protection_Overview#Fundamental Principles of Radiological Protection | fundamental principles]] of justification and optimisation.
These limits apply only to doses received above the normal local [[Sources of Radiation Exposure | natural background radiation]].
Limits on [[System_of_radiation_protection_module_2#Effective Dose | effective dose]], combined with optimisation of protection, are designed to avoid a risk of [[Effects of Exposure | stochastic effects]] that would be considered intolerable in a [[System_of_radiation_protection_module_2#Exposure Categories and Situations | planned exposure situation]].
Limits on [[Absorbed, System_of_radiation_protection_module_2#Equivalent, and Effective Dose | equivalent dose to an organ]], combined with optimisation of protection, are designed to prevent the occurance of [[Effects of Exposure | deterministic effects]].
Dose limits apply only in [[System_of_radiation_protection_module_2#Exposure Categories and Situations | planned exposure situations]]. In other situations, restrictions on individual dose are called reference levels. They provide the additional flexibility needed in [[System_of_radiation_protection_module_2#Exposure Categories and Situations | emergency and existing exposure situations]] to make sure protection is optimised.
Dose limits do not apply to [[System_of_radiation_protection_module_2#Exposure Categories and Situations | medical exposures]]. If they did, the effectiveness of diagnosis or treatment might be reduced, doing more harm than good for the patient. The emphasis is on justification of medical procedures and optimisation of protection.
