a

where the total quantity taken together of each of the radionuclides listed in column 1 of Table A below present in the clocks and watches on any premises does not exceed the amount set out in column 2–

TABLE A

Radioactive material	Relevant value
Tritium	109 becquerels
Promethium 147	107 becquerels
Radium 226	104 becquerels

or

b

where

i

the total quantity of the radionuclides listed in column 2 of Table B below present in each such clock or watch of the type listed in column 1 of that table does not exceed the amount set out in column 3–

TABLE B

Type of clock or watch	Radioactive material	Relevant value (becquerels)
i Luminised time measurement instruments3- a worn or carried on the person	Tritium Promethium 147	2.8 × 108 5.5 × 106
b not worn or carried on the person	Tritium Promethium 147	3.7 × 108 7.4 × 106
ii Special luminised time measurement instruments4	Tritium Promethium 147	9.3 × 108 1.9 × 107
iii Watches containing gaseous tritium light sources5	Tritium	7.4 × 109
iv Radium luminised timepieces6- a wristwatches	Radium 226	3.7 × 103
b alarm clocks	Radium 226	5.5 × 103
c special time measurement instruments	Radium 226	5.6 × 104

• and

ii

no more than five items falling within Table B which constitute radioactive waste are present on any premises