Which of the following facilitates comparison between different radiations?
EQUIVALENT (RADIATION-WEIGHTED) DOSE:
The equivalent dose (HT) is used to compare the biologic effects of different types of radiation on a tissue or organ. Particulate types of radiation have a high LET and are more damaging to tissue than radiation with low LET, such as x rays. This relative biologic effectiveness of different types of radiation is called  the radiation-weighting  factor (WR).
The unit of equivalent dose is the sievert (Sv). For diagnostic x-ray examinations, 1 Sv equals 1 Gy. 
The traditional unit of equivalent dose is the rem (roentgen equivalent man); 1 Sv  equals 100 rem.
Oral Radiology, Principles and Interpretation / Stuart C. White, Michael J. Pharoah - 7th ed - pg - 15
Rad
Rem
Quality factor exposure
Roentgen