Radiation Protection In Veterinary Medicine - Recommended Safety Procedures For Installation And Use Of Veterinary X-ray Equipment - Safety Code 28

Appendix II (Continued)
Shielding Guides for Veterinary X-Ray Facilities

Table 3. Commercial Lead Sheets

Thickness		Nominal weight lb/ft2	Nominal weight kg/m2
Inches	Millimetres
1/64	0.4	1	4.9
3/128	0.6	1½	7.3
1/32	0.8	2	9.8
5/128	1.0	2½	12.2
3/64	1.2	3	14.6
7/128	1.4	3½	17.1
1/16	1.6	4	19.5
5/64	2.0	5	24.4
3/32	2.4	6	29.3

Notes:

1. The density of commercially rolled lead is 11.36 g.cm^-3.
2. The commercial tolerances are ± 0.13 mm for lead up to 1.4 mm and ± 0.8 mm for heavier sheets.
3. Material and installation costs for lead sheet less than 0.8 mm thick are frequently higher than for heavier sheet.
4. Acoustical type lead is not suitable for lead shielding.

Use of Common Construction Materials For X-Ray Shielding

Commonly used construction materials provide a certain degree of protection against X-radiation. This degree will depend on the type and thickness of the material in question and on the X-ray tube voltage at which the equipment is operated. In some cases a judicious use of common building materials or a careful selection of location and orientation of the X-ray unit may eliminate the need for additional shielding without compromising the X-ray safety of the installation.

X-ray shielding properties of some common construction materials and their combinations are given below. Note that thicknesses of different materials that provide equivalent attenuation under one set of conditions may behave quite differently under other conditions. The materials described in Table 4 are not well suited for use as primary shielding. They should be regarded as materials for use in secondary shielding.

Table 4. Approximate Concrete Equivalence of Common Construction Materials

Material	Thickness of concrete (cm)
	50 kVp	70 kVp	85 kVp	100 kVp	125 kVp	150 kVp
1	10	10	10	10	10	10
2	7	7	7	7	7	7
3	2.3	2.3	2.3	2.3	(*)	(*)
4	0.5	0.5	0.5	0.5	(*)	(*)
5	0.8	0.8	0.8	0.8	(*)	(*)
6	1.0	1.0	1.0	1.0	(*)	(*)
7	1.4	1.4	1.4	1.4	(*)	(*)
8	1.2	1.2	1.2	1.2	1.2	1.2
9	2.4	2.2	2.2	2.2	2.2	2.2