Arizona Administrative Code
Title 9 - HEALTH SERVICES
Chapter 7 - DEPARTMENT OF HEALTH SERVICES - RADIATION CONTROL
Article 1 - GENERAL PROVISIONS
Section R9-7-105 - Quality Factors for Converting Absorbed Dose to Dose Equivalent
Current through Register Vol. 30, No. 38, September 20, 2024
A. As used in these rules, the quality factors for converting absorbed dose to dose equivalent are shown in
Table I.
TABLE I. QUALITY FACTORS AND ABSORBED DOSE EQUIVALENCIES
TYPE OF RADIATION |
Quality Factor (Q) |
Absorbed Dose Equal to a Unit Dose Equivalenta |
X, gamma, or beta radiation and high-speed electrons |
1 |
|
Alpha particles, multiple-charged particles, fission fragments, and heavy particles of unknown charge |
20 |
0.05 |
Neutrons of unknown energy |
10 |
0.1 |
High-energy protons |
10 |
0.1 |
a The absorbed dose in gray is equal to 1 Sv or the absorbed dose in rad is equal to 1 rem.
B. If it is more convenient to measure the neutron fluence rate than to determine the neutron dose equivalent rate in sievert per hour or rem per hour, 0.01 Sv (1 rem) of neutron radiation of unknown energies may, for purposes of these rules, be assumed to result from a total fluence of 25 million neutrons per square centimeter incident upon the body. If sufficient information exists to estimate the approximate energy distribution of the neutrons, the licensee or registrant may use the fluence rate per unit dose equivalent or the appropriate Q value from Table II to convert a measured tissue dose in gray or rad todose equivalent in sievert or rem.
TABLE II. MEAN QUALITY FACTORS, Q, AND FLUENCE PER UNIT DOSE EQUIVALENT FOR MONOENERGETIC NEUTRONS
Neutron Energy (meV) |
Quality Factor (Q) |
Fluence per Unit Dose Equivalentb (neutrons cm-2 rem-1) |
Fluence per Unit Dose Equivalentb (neutrons cm-2 Sv-1) |
(thermal) 2.5E-8 |
2 |
980E+6 |
980E+8 |
1E-7 |
2 |
980E+6 |
980E+8 |
1E-6 |
2 |
810E+6 |
810E+8 |
1E-5 |
2 |
810E+6 |
810E+8 |
1E-4 |
2 |
840E+6 |
840E+8 |
1E-3 |
2 |
980E+6 |
980E+8 |
1E-2 |
2.5 |
1010E+6 |
1010E+8 |
1E-1 |
7.5 |
170E+6 |
170E+8 |
5E-1 |
11 |
39E+6 |
39E+8 |
1 |
11 |
27E+6 |
27E+8 |
2.5 |
9 |
29E+6 |
29E+8 |
5 |
8 |
23E+6 |
23E+8 |
7 |
7 |
24E+6 |
24E+8 |
10 |
6.5 |
24E+6 |
24E+8 |
14 |
7.5 |
17E+6 |
17E+8 |
20 |
8 |
16E+6 |
16E+8 |
40 |
7 |
14E+6 |
14E+8 |
60 |
5.5 |
16E+6 |
16E+8 |
1E+2 |
4 |
20E+6 |
20E+8 |
2E+2 |
3.5 |
19E+6 |
19E+8 |
3E+2 |
3.5 |
16E+6 |
16E+8 |
4E+2 |
3.5 |
14E+6 |
14E+8 |
a Value of quality factor (Q) at the point where the dose equivalent is maximum in a 30-centimeter diameter cylinder tissue-equivalent phantom.
b Monoenergetic neutrons incident normally on a 30-centimeter diametercylinder tissue-equivalent phantom.