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TABLE 1.-HATCHWAY BEAMS AND FORE-AND-AFTERS FOR VESSELS 200 FEET OR MORE IN LENGTH -Continued

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A-Plain angle.

BP-Bulb plate.

P=Plate.

D=Depth.

B=Breadth.

In vessels not exceeding 100 feet in length, the depths of beams which are formed of plates and angles may be 60 percent of the depths given above; the depths of beams and
steel fore-and-afters formed of bulb angle or bulb plate section may be 80 percent of the depths given above; the thickness of plates, bulb angles, and bulb plates should correspond
to the thickness tabulated for the reduced depths with a minimum thickness of 0.30 inch; the depths and breadths of wood fore-and-afters may be 80 percent of those given in the
tables for side fore-and-afters, but the center fore-and-afters must be not less than 61⁄2 inches wide. In vessels between 100 feet and 200 feet in length, the sizes of the beams and fore-
and-afters are to be determined by linear interpolation.

Depths for hatchway beams are at the middle of the length and are measured from the top mounting to the lower edge. Depths for fore-and-afters are measured from the
underside of the hatch covers to the lower edge. Sizes for intermediate lengths and spacing are obtained by interpolation. Where plates are specified, two angles of the size
given for mountings, are to be fitted at the upper and at the lower part of the beam. Where bulb plates are specified, two angles, of the size given for mountings, are to be fitted
at the upper part of the beam or fore-and-after. Where bulb angles are specified, one angle, of the size given for mountings, is to be fitted at the upper part of the section. Where
the specified flanges of an angle are of different dimensions, the larger flange is to be horizontal,

6' 0".
8' 0".
10' 0".

TABLE 2.-HATCHWAY BEAMS AND FORE-AND-AFTERS FOR VESSELS 200 FEET OR MORE IN LENGTH

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TABLE 2.-HATCHWAY BEAMS AND FORE-AND-AFTERS FOR VESSELS 200 FEET OR MORE IN LENGTH -Continued

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D=Depth.

B=Breadth,

1 In vessels not exceeding 100 feet in length, the depths of beams which are formed of plates and angles may be 60 percent of the depths given above; the depths of beams
and steel fore-and-afters formed of bulb angle or bulb plate section may be 80 percent of the depths given above; the thickness of plates, bulb angles, and bulb plates should
correspond to the thickness tabulated for the reduced depths with a minimum thickness of 0.30 inch; the depths and breadths of wood fore-and-afters may be 80 percent of those
given in the tables for side fore-and-afters, but the center fore-and-afters must be not less than 61⁄2 inches wide. In vessels between 100 feet and 200 feet in length, the sizes of
the beams and fore-and-afters are to be determined by linear interpolation.

Depths for hatchway beams are at the middle of the length and are measured from the top mounting to the lower edge. Depths for fore-and-afters are measured from the
under side of the hatch covers to the lower edge. Sizes for intermediate length and spacing are obtained by interpolation. Where plates are specified, two angles, of the sizes
given for mountings, are to be fitted at the upper and at the lower part of the beam. Where bulb plates are specified, two angles, of the size given for mountings, are to be fitted
at the upper part of the beam or fore-and-after. Where bulb angles are specified, one angle, of the size given for mountings, is to be fitted at the upper part of the section. Where
the specified flanges of an angle are of different dimensions, the larger flange is to be horizontal.

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A Plain angle.

BP-Bulb plate.

P=Plate.

Carriers

§ 43.12 Carriers or sockets. or sockets for hatchway beams and foreand-afters are to be of steel at least onehalf inch thick, and are to have a width of bearing surface of at least 3 inches.

§ 43.13 Cleats. Strong cleats at least 21⁄2 inches wide are to be fitted at intervals of not more than 2 feet from center to center; the end cleats are to be placed not more than 6 inches from each corner of the hatchway.

§ 43.14 Battens and wedges. Battens and wedges are to be efficient and in good condition.

§ 43.15 Tarpaulins. At least two tarpaulins in good condition, thoroughly waterproofed and of ample strength, are to be provided for each hatchway in an exposed position on freeboard and superstructure decks. The material is to be guaranteed free from jute, and shall not be less than No. 4 cotton canvas or No. 6 hemp canvas before waterproofing.

§ 43.16 Security of hatchway covers. (a) At all hatchways in exposed positions on freeboard and superstructure decks ring bolts or other fittings for lashings are to be provided.

(b) Where the breadth of the hatchway exceeds 60 percent of the breadth of the deck in way of the hatchway, and the coamings are required to be 24 inches high, fittings for special lashings are to be provided for securing the hatchway covers after the tarpaulins are battened down.

§ 43.17 Cargo and other hatchways in the freeboard deck within superstructures which are fitted with closing appliances less efficient than class 1. The construction and fittings of such hatchways are to be at least equivalent to the standards laid down in § 43.18.

§ 43.18 Hatchway coamings and closing arrangements. (a) Cargo, coaling, and other hatchways in the freeboard deck within superstructures which are fitted with class 2 closing appliances are to have coamings at least 9 inches in height and closing arrangements as effective as those required for exposed cargo hatchways whose coamings are 18 inches high.

(b) Where the closing appliances are less efficient than class 2, the hatchways

are to have coamings at least 18 inches in height, and are to have fittings and closing arrangements as effective as those required for exposed cargo hatchways.

CROSS REFERENCE: For class 1 and class 2 closing appliances, see §§ 43.43, 43.44.

§ 43.19 Machinery space openings in exposed positions on freeboard and raised quarter decks. (a) Such openings are to be properly framed and efficiently inclosed by steel casings of ample strength, and where the casings are not protected by other structures their strength is to be specially considered. Doors in such casings are to be of steel, efficiently stiffened, permanently attached, and capable of being closed and secured from both sides. The sills of openings are to be at least 24 inches above the freeboard deck and at least 18 inches above the raised quarter deck.

(b) Fiddley, funnel, and ventilator coamings are to be as high above the deck as is reasonable and practicable. Fiddley openings are to have strong steel covers permanently attached in their proper positions.

§ 43.20 Machinery space openings in exposed positions on superstructure decks other than raised quarter decks. (a) Such openings are to be properly framed and efficiently inclosed by strong steel casings. Doors in such cases are to be strongly constructed, permanently attached, and capable of being closed and secured from both sides. The sills of the openings are to be at least 15 inches above superstructure decks.

(b) Fiddley, funnel, and ventilator coamings are to be as high above the deck as is reasonable and practicable. Fiddley openings are to have strong steel covers permanently attached in their proper positions.

§ 43.21 Machinery space openings in the freeboard deck within superstructures which are fitted with closing appliances less efficient than class 1. Such openings are to be properly framed and efficiently inclosed by steel casings. Doors in such casings are to be strongly constructed, permanently attached, and capable of being securely closed. The sills of the openings are to be at least 9 inches above the deck where the superstructures are closed by class 2 closing appliances, and at least 15 inches above

the deck where the closing appliances are less efficient than class 2.

CROSS REFERENCES: For class 1 and class 2 closing appliances, see §§ 43.43, 43.44.

§ 43.22 Flush bunker scuttles. Flush bunker scuttles may be fitted in superstructure decks, and where so fitted are to be of iron or steel, of substantial construction, with screw or bayonet joints. Where a scuttle is not secured by hinges, a permanent chain attachment is to be provided. The position of flush bunker scuttles in small vessels in special trades is to be dealt with by each assigning authority.

Compan

§ 43.23 Companionways. ionways in exposed positions on freeboard decks and on decks of inclosed superstructures are to be of substantial construction. The sills of the doorways are to be of the heights specified for hatchway coamings (see §§ 43.9, 43.18). The doors are to be strongly constructed and capable of being closed and secured from both sides. Where the companionway is situated within a quarter of the vessel's length from the stem, it is to be of steel and riveted to the deck plating.

§ 43.24 Ventilators in exposed positions on freeboard and superstructure decks. (a) Such ventilators to spaces below freeboard decks or decks of superstructures which are intact or fitted with class 1 closing appliances are to have coamings of steel, substantially constructed, and efficiently connected to the deck by rivets spaced four diameters apart center to center, or by equally effective means. The deck plating at the base of the coamings is to be efficiently stiffened between the deck beams. The ventilator openings are to be provided with efficient closing arrangements.

(b) Where such ventilators are situated on the freeboard deck, or on the superstructure deck within a quarter of the vessel's length from the stem, and the closing arrangements are of a temporary character, the coamings are to be at least 36 inches in height; in other exposed positions on the superstructure deck they are to be at least 30 inches in height. Where the coaming of any ventilator exceeds 36 inches in height, it is to be specially supported and secured.

§ 43.25 Air pipes. Where the air pipes to ballast and other tanks extend above the freeboard or superstructure

decks, the exposed parts of the pipes are to be of substantial construction; the height from the deck to the opening is to be at least 36 inches in wells on freeboard decks, 30 inches on raised quarter decks, and 18 inches on other superstructure decks. Satisfactory means are to be provided for closing the openings of the air pipes.

§ 43.26 Gangway, cargo, and coaling ports. Openings in the sides of vessels below the freeboard deck are to be fitted with watertight doors or covers, which, with their securing appliances, are to be of sufficient strength.

§ 43.27 Scuppers and sanitary discharge pipes. (a) Discharges from scuppers and sanitary pipes led through the vessel's sides from spaces below the freeboard deck are to be fitted with efficient and accessible means for preventing water from passing inboard. Each separate discharge may have an automatic nonreturn valve with a positive means of closing it from a readily accessible position above the freeboard deck, or two automatic nonreturn valves without positive means of closing, provided the upper valve is situated so that it is always accessible for examination under service conditions. The positive-action valve is to be accessible and is to be provided with means for showing whether the valve is opened or closed.

(b) Conditional upon the type and the location of the inboard ends of such openings, similar provisions may be prescribed by the assigning authority as to discharge from spaces within inclosed superstructures.

(c) Where scuppers are fitted in superstructures not fitted with class 1 closing appliances they are to have efficient means for preventing the accidental admission of water below the freeboard deck.

[Order 205, 7 F. R. 604, as amended at 11 F. R. 4668]

§ 43.28 Air ports. (a) Air ports to spaces below the freeboard deck or to spaces below the superstructure deck of superstructures closed by class 1 or class 2 closing appliances are to be fitted with efficient inside deadlights permanently attached in their proper positions so that they can be effectively closed and secured water-tight.

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