2.—(1) Without prejudice to the generality of section fifty-five of the Act the manager of every mine shall take such steps as are necessary for securing that every airway therein which as regards any working face is an intake airway and the air in which has not previously ventilated a working face shall normally be kept free from inflammable gas:
(2) For the purposes of this regulation an airway shall be deemed not to be normally kept free from inflammable gas if the average percentage by volume of inflammable gas found in six samples of air taken by an inspector in the general body of the air in that airway at intervals of not less than fourteen days exceeds one quarter.
3.—(1)
(2) Where in any part of a mine of coal the use of lamps or lights, other than permitted lights, is unlawful and in any part of that mine which comprises a working face shots are fired in the ordinary course of working, the manager shall make and secure the efficient carrying out of arrangements whereby determinations of the firedamp content are made in accordance with the provisions of the four next following regulations in the part of the mine in which shots are so fired.
4.—(1) Determinations of the firedamp content shall be made—
(a)by means of apparatus of a type approved for the purpose by the Minister, by a competent person appointed for that purpose by the manager of the mine; or
(b)by means of samples of air taken by a competent person so appointed and analysed within four days of the taking thereof.
(2) In reckoning a period of four days for the purposes of this regulation no account shall be taken of any Saturday, Sunday or day of general holiday.
5.—(1) Where determinations of the firedamp content in any part of a mine which comprises a longwall face are required to be made by virtue of the use of electric power at or within one hundred and fifty feet of that face or the firing of shots in that part of the mine, those determinations shall be made at or as near as is practicable to the point in each airway serving that face thirty feet from the nearest working place at that face. If the air ventilating that long-wall face has ventilated or will ventilate another longwall face determinations shall also be made at such a point in each airway serving each such other face.
(2) An inspector may serve on the manager of the mine a notice requiring determinations to be made also at such additional point at any such longwall face as may be specified in the notice.
6.—(1) Where determinations of the firedamp content in any part of a mine which comprises a working face other than a longwall face are required to be made by virtue of the use of electric power at or within one hundred and fifty feet of that face or the firing of shots in that part of the mine, those determinations shall be made at suitable points fixed by the manager in respect of each air current in that part of the mine.
(2) An inspector may, if he is of opinion that any point so fixed is unsuitable, serve on the manager a notice requiring him to fix some other point in substitution therefor and may serve on the manager a notice requiring determinations to be made at some other point specified in the notice in addition to those required by the preceding paragraph.
7.—(1) Determinations of the firedamp content shall be made at every point required by or under the two last preceding regulations once in every week:
(a)if any determination at any such point shows a firedamp content exceeding 0·8 per cent. by volume determinations shall be made at the corresponding point at intervals not exceeding twenty-four hours so long as the content is shown to exceed or to have exceeded that percentage and for the seven next following working days, unless an inspector by notice served on the manager otherwise consents;
(b)if every determination made during a period of thirty days at any such point showed a firedamp content not exceeding 0·6 per cent. by volume it shall be sufficient to make determinations at the corresponding point at intervals not exceeding thirty days for so long as the firedamp content shown thereby does not exceed that percentage.
(2) Notwithstanding anything in the last preceding paragraph whenever any alteration is made in the arrangements for ventilating a mine which affects or may affect substantially any part of the mine in which determinations of the firedamp content have to be made, a determination of the firedamp content at each point in that part shall be made as soon as any substantial effect of the alteration would be apparent.
(3) Any determination of the firedamp content shall be made, if the relevant face is machine-cut, during the latter part of the cutting shift or, if the face is not machine-cut, during the latter part of the filling shift:
(4) The provisions of Part XV of the Act with respect to references upon notices served by inspectors shall apply to a notice of requirement under the last preceding paragraph and either of the following shall be a relevant ground of objection to such a notice, namely—
(a)that the firedamp content at the point in question is not normally greatest at the stage referred to in the notice;
(b)that the greater firedamp content at that stage at that point is transitory.
(5) Where determinations of firedamp content are made once in every week or thirty days they shall as far as practicable be made at the appropriate stage of the operations on the last working day of the week, other than a Saturday, on which the operations comprise that stage.
8.—(1) Particulars of every determination of firedamp content made in accordance with these regulations shall be recorded forthwith in a book provided for that purpose by the owner of the mine.
(2) If any determination shows a firedamp content at any point exceeding one per cent. by volume the manager of the mine shall forthwith give notice thereof to the inspector for the district unless—
(a)the excess was caused by temporary derangement of the ventilation at the mine which has been remedied; or
(b)the inspector by notice served on the manager has otherwise directed.
9.—(1) The manager of every mine shall make and secure the efficient carrying out of arrangements whereby the quantity of air passing each of the points hereinafter mentioned is measured at intervals not exceeding thirty days.
(2) The points at which such measurements are to be taken are—
(a)in every intake airway starting at an entrance to a shaft or outlet, a point as near as is practicable to that entrance;
(b)in every split by which air leaves an air current except a split at a longwall face, a point as near as is practicable to the junction;
(c)in any part of the mine in which determinations of firedamp content are required to be made, the points at which those determinations are made, excluding any point at which determinations are made because it has been specified in a notice served on the manager by an inspector; and
(d)in any part of the mine containing a working face, being a part in which determinations of firedamp content are not required to be made under these regulations, a point in each road, which as regards a working face is an intake airway and the air in which has not previously ventilated a working face, as nearly as practicable four hundred and fifty feet from the nearest part of the said working face with respect to which that road is an intake airway, unless that point would be within three hundred feet of a point at which measurements are taken under sub-paragraph (a) or (b).
(3) A measurement of the quantity of air at a point specified in sub-paragraph (c) of the last preceding paragraph shall be taken on an occasion when a determination of firedamp content is made thereat.
(4) Notwithstanding anything in paragraph (1) of this regulation, whenever any alteration is made in the arrangements for ventilating a mine which affects or may affect substantially the quantity of air passing any point at which measurements thereof have to be taken, a measurement of the quantity at each such point shall be taken as soon as any substantial effect of the alteration would be apparent.
(5) Particulars of every measurement taken in accordance with this regulation shall be recorded forthwith in a book provided for the purpose by the owner of the mine together with any other information incidental thereto for which provision is made in that book.