156. An x-ray machine to be used at voltages higher than 70 kV must be equipped with a filter set in the machine to ensure total aluminium-equivalent filtration of at least 2.5 mm.
An x-ray machine to be used at voltages lower than 50 kV must be equipped with a filter set in the machine to ensure total aluminium-equivalent filtration of at least 0.5 mm.
An x-ray machine to be used at voltages higher than 50 kV but lower than 70 kV must be equipped with a filter set in the machine to ensure a total aluminium-equivalent filtration of at least 1.5 mm.
An x-ray machine to be used at any voltage and not equipped with a filter set in must be equipped in such a way as to disallow exposure unless it ensures filtration equivalent to that provided for in the first, second and third paragraphs.
R.R.Q., 1981, c. P-35, r. 1, s. 156.