Difference Between Becquerel and Sievert

The key difference between becquerel and sievert is that becquerel is a unit used to measure the activity of a quantity of radioactive material whereas sievert is a unit used to measure the health effects of ionizing radiation.

Becquerel and sievert are units of measurement. Both these are SI derived units. SI derived units are units of measurement that are derived from the seven base units specified by the International System of Units (SI units). These seven base units are kilogram, seconds, kelvin, ampere, mole, candela and meter.

CONTENTS

1. Overview and Key Difference
2. What is Becquerel 
3. What is Sievert
4. Side by Side Comparison – Becquerel vs Sievert in Tabular Form
5. Summary

What is Becquerel

Becquerel is an SI derived unit we can use to measure the activity of a quantity of radioactive material. Therefore, it is the unit of specific activity. The symbol for becquerel is Bq. This unit was named after the scientist Henri Becquerel who introduced the unit. The SI base unit that is used for derivation of becquerel is seconds (s). One becquerel is equal to s-1 (per second). This means one becquerel is equal to the activity of a quantity of radioactive material in which one nucleus decays per second. The relationship is as follows:

1 Bq = 1 s-1

Figure 01: Measurement of Radioactivity

When naming this SI derived unit, there are two common rules we have to keep in mind. The first rule is that, when giving the symbol of the unit, the letter “B” always has to be capital because this unit was named after a person whose name. The second rule is that when writing the name of this unit in English, we have to write the letter “b” in simple letters if it is not at the beginning of a sentence. Moreover, similar to any other SI unit, we can use prefixes with becquerel such as kilobecquerel (kBq), megabecquerel (MBq), etc.

What is Sievert?

Sievert is an SI derived unit we can use to measure the ionizing radiation dose. The symbol of this unit is Sv. It is a measure of the health effect of low levels of ionizing radiation on the human body. This unit is important in experiments regarding dosimetry and radiation protection. This unit was named after the scientist Rolf Maximilian Sievert. The SI base units that are used to derive the Sievert are meter and seconds. Here, one Sievert equals m2s-2.

1Sv = 1 m2s-2

When naming this SI derived unit, there are two common rules that we have to keep in mind. The first rule is that, when giving the symbol of the unit, the letter “S” has to be always capital because this unit was named after a person whose name is used to derive the symbol. The second rule is that, when writing the name of this unit in English, we have to write the letter “s” in simple letters if it is not at the beginning of a sentence.

What is the Difference Between Becquerel and Sievert?

Becquerel and Sievert are units of measurement. Both these are SI derived units. SI derived units are the units of measurement that are derived from the seven base units specified by the International System of Units (SI units). The key difference between Becquerel and Sievert is that Becquerel is a unit used to measure the activity of a quantity of radioactive material, whereas Sievert is a unit used to measure the health effects of ionizing radiation.

Below infographic summarizes the difference between Becquerel and Sievert.

Summary – Becquerel vs Sievert

Becquerel and Sievert are units of measurement. Both these are SI derived units. SI derived units are the units of measurement that are derived from the seven base units specified by the International System of Units (SI units). The key difference between Becquerel and Sievert is that Becquerel is a unit that measures the activity of a quantity of radioactive material, whereas Sievert is a unit that measures the health effects of ionizing radiation.