Any person designated in writing for the purpose by a sewerage undertaker shall, on producing any duly authenticated document showing his authority, have a right to enter any premises at all reasonable hours-
Part I of Schedule 6 to this Act shall apply to the right of entry conferred by subsection (1) above.
Any person designated by a sewerage undertaker under subsection (1) above for the purpose of exercising any power under this section for the purposes of Chapter III of Part IV of this Act may, on any occasion on which he so exercises that power in relation to any premises, obtain and take away any sample of any trade effluent which is passing (either directly or through a drain or private sewer) from those premises into any of the undertaker's public sewers.
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In this section "trade effluent" and "trade premises" have the same meanings as in Chapter III of Part IV of this Act; and, accordingly, section 139 above shall have effect for the purposes of this section as it has effect for the purposes of that Chapter.