Merchant Shipping (Safety and Load Line Conventions) Act 1932

Openings in Freeboard and Superstructure Decks.

RULE VIII Cargo and other Hatchways not protected by Superstructures.

The construction and fitting of cargo and other hatchways in exposed positions on freeboard and superstructure decks are to be at least equivalent to the standards laid down in Rules IX to XVI.

RULE IX Hatchway Coamings.

The height of hatchway coamings on freeboard decks is to be at least 24 inches above the deck. The height of coamings on superstructure decks is to be at least 24 inches above the deck if situated within a quarter of the ship's length from the stem, and at least 18 inches if situated elsewhere.

Coamings are to be of steel, are to be substantially constructed and, where required to be 24 inches high, are to be fitted with an efficient horizontal stiffener placed not lower than 10 inches below the upper edge, and fitted with efficient brackets or stays from the stiffener to the deck, at intervals of not more than 10 feet. Where end coamings are protected, these requirements may be modified.

RULE X Hatchway Covers.

Covers to exposed hatchways are to be efficient, and where they are made of wood, the finished thickness is to be at least 2 3/8 inches in association with a span of not more than 5 feet. The width of each bearing surface for these hatchway covers is to be at least 2 ½ inches.

RULE XI Hatchway Beams and Fore-and-Afters.

Where wood hatchway covers are fitted the hatchway beams and fore-and-afters are to be of the scantlings and spacing given in Table 1 where coamings 24 inches high are required, and as given in Table 2 where coamings 18 inches high are required. Angle bar mountings on the upper edge are to extend continuously for the full length of each beam. Wood fore-and-afters are to be steel shod at all bearing surfaces.

TABLE 1

(Coamings 24 inches in height.)

HATCHWAY Beams and Fore-and-Afters for Ships 200 feet or more in length.^*

HATCHWAY BEAMS.

Breadth of Hatchway.	Mounting.			Beams with Fore-and-Afters.						Beams without Fore-and-Afters.
				Spacing Centre to Centre.						Spacing Centre to Centre.
				6' 0'		8' 0'		10' 0'		4' 0'		5' 0'
	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.
10' 0"	3 x	3 x	.40A	11 x	.30P	12 x	.32P	14 x	.34P	9 x	.46BP	10 x	.50BP
12' 0"	3 x	3 x	.40A	12 x	.32P	14 x	.34P	17 x	.36P	11 x	.50BP	12 x	.50BP
14' 0"	3 x	3 x	.42A	14 x	.34P	17 x	.36P	20 x	.38P	12 x	.50BP	12 x	.32P
16' 0"	3x	3 x	.42A	16 x	.36P	19 x	.38P	22 x	.38P	12 x	.32P	14 x	.34P
18' 0'	4 x	3 x	.44A	18 x	.36P	21 x	.38P	25 x	.40P	14 x	.34P	16 x	.36P
20' 0"	4 x	3 x	.44A	20 x	.38P	24 x	.40P	28 x	.42P	15 x	.34P	18 x	.36P
22' 0"	4 x	3 x	.46A	22 x	.38P	26 x	.42P	30 x	.44P	16 x	.36P	19 x	.36P
24' 0"	5 x	3 x	.46A	23 x	.40P	28 x	.42P	32 x	.44P	17 x	.36P	20 x	.38P
26' 0"	5 x	3 x	.48A	24 x	.40P	29 x	.42P	34 x	.46P	18 x	.36P	21 x	.38P
28' 0"	6 x	3 x	.50A	25 x	.40P	31 x	.44P	36 x	.48P	19 x	.38P	22 x	.38P
30' 0"	6 x	3 x	.52A	26 x	.42P	32 x	.44P	38 x	.48P	20 x	.38P	23 x	.40P

FORE-AND-AFTERS.

Length of Fore-and-Afters.	Mounting.			Bulb Plate. Centre Fore-and-Afters.						Bulb Angle. Side Fore-and-Afters.
				Spacing Centre to Centre.						Spacing Centre to Centre.
				3' 0"		4' 0"		5' 0"		3' 0"			4' 0"			5' 0"
	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.
6' 0"	2 ½ x	2 ½ x	.36	6 x	.36	6 ½ x	.38	7 x	.38	6 x	3 x	.38	6 ½ x	3 ½ x	.38	7 x	3 ½ x	.38
8' 0"	2 ½ x	2 ½ x	.38	7 x	.42	8 x	.44	9 x	.44	7 x	3 ½ x	.42	8 x	3 x	.44	9 x	3 ½ x	.44
10' 0"	2 ½ x	2 ½ x	.40	8 x	.50	9 ½ x	.50	11 x	.50	8 x	3 ½ x	.50	9 ½ x	3 ½ x	.50	11 x	3 ½ x	.50

—	Wood Centre Fore-and-Afters.						Wood Side Fore-and-Afters.
	Spacing Centre to Centre.						Spacing Centre to Centre.
	3' 0"		4' 0"		5' 0"		3' 0"		4' 0"		5' 0"
	D	B	D	B		B	D	B	D	B	D	B
A = Plain angle. BP = Bulb plate. P = Plate. D = Depth. B = Breadth.
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 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.
* In ships not exceeding 100 feet in length, the depths of beams which are formed of plates and angles may be 60 per cent. 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 per cent. 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 .30 inch; the depths and breadths of wood fore-and-afters may be 80 per cent. of those given in the tables for side fore-and-afters, but the centre fore-and-afters must be not less than 6 ½ inches wide. In ships between 100 feet and 200 feet in length, the sizes of the beams and fore-and-afters are to be determined by linear interpolation.
	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.
6' 0"	5 ½	7	6	7	6 ½	7	5 ½	5 ½	6	6	6 ½	6
8' 0"	6 ½	7	7 ½	7	8	7	6 ½	6 ½	7 ½	7	8	7
10' 0"	8	7	8 ½	8	9	9	8	7	8 ½	8	9	9

TABLE 2

(Coamings 18 inches in height.)

HATCHWAY Beams and Fore-and-Afters for Ships 200 feet or more in length.^*

HATCHWAY BEAMS.

Breadth of Hatchway.	Mounting.			Beams with Fore-and-Afters.						Beams without Fore-and-Afters.
				Spacing Centre to Centre.						Spacing Centre to Centre.
				6' 0'		8' 0'		10' 0'		4' 0'		5' 0'
	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.
10' 0"	3 x	3 x	.40A	9 ½ x	.46BP	10 ½ x	.50BP	11 ½ x	.52BP	8 x	.40BP	9 x	.44BP
12' 0"	3 x	3 x	.40A	11 x	.50BP	11 x	.30P	13 x	.34P	9 x	.46BP	10 x	.50BP
14' 0"	3 x	3 x	.42A	11 x	.30P	13 x	.32P	15 x	.34P	10 x	.50BP	11 ½ x	.50BP
16' 0"	3 ½ x	3 x	.42A	12 x	.32P	15 x	.34P	17 x	.36P	11 x	.30P	11 x	.30P
18' 0"	4 x	3 x	.44A	14 x	.34P	17 x	.36P	19 x	.38P	11 x	.30P	12 x	.32P
20' 0"	4 x	3 x	.44A	16x	.36P	19 x	.38P	21 x	.38P	12 x	.32P	13 x	.34P
22' 0"	4 ½ x	3 x	.46A	17 x	.36P	20 x	.38P	23 x	.40P	12 ½ x	.32P	14 x	.34P
24' 0"	5 x	3 ½ x	.46A	18 x	.36P	21 x	.38P	25 x	.40P	13 x	.34P	14 ½ x	.34P
26' 0"	5 ½ x	3 ½ x	.48A	19 x	.38P	22 x	.38P	26 x	.42P	13 ½ x	.34P	15 x	.34P
28' 0"	6 x	3 ½ x	.50A	20 x	.38P	23 x	.40P	27 x	.42P	14 x	.34P	16 x	.36P
30' 0"	6 x	3 ½ x	.52A	21 x	.38P	24 x	.40P	28 x	.42P	15 x	.34P	17 x	.36P

FORE-AND-AFTERS.

Length of Fore-and-Afters.	Mounting.			Bulb Plate. Centre Fore-and-Afters.						Bulb Angle. Side Fore-and-Afters.
				Spacing Centre to Centre.						Spacing Centre to Centre.
				3' 0"		4' 0"		5' 0"		3' 0"			4' 0"			5' 0"
	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.
6' 0"	2 ½ x	2 ½ x	.36	5 x	.34	5 ½ x	.34	6 x	.36	5 x	3 x	.34	5½ x	3 x	.34	6 x	3 x	.36
8' 0"	2 ½ x	2 ½ x	.38	6 x	.38	7 x	.40	7 ½ x	.42	6 x	3 x	.38	7x	7 x	.40	7 ½ x	3 ½ x	.42
10' 0"	2 ½ x	2 ½ x	.40	7 x	.44	8 x	.46	9 x	.50	7 x	3 x	.44	8 x	3 ½ x	.56	9 x	3 ½ x	.50

—	Wood Centre Fore-and-Afters.						Wood Side Fore-and-Afters.
	Spacing Centre to Centre.						Spacing Centre to Centre.
	3' 0"		4' 0"		5' 0"		3' 0"		4' 0"		5' 0"
	D	B	D	B	D	B	D	B	D	B	D	B
A = Plain angle. BP = Bulb plate. P = Plate. D = Depth. B—Breadth.
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 lengths 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.
* In ships not exceeding 100 feet in length, the depths of beams which are formed of plates and angles may be 60 per cent. 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 per cent. 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 .30 inch; .the depths and breadths of wood fore-and-afters may be 80 per cent. of those given in the tables for side fore-and-afters, but the centre fore-and-afters must be not less than 6½ inches wide. In ships between 100 feet and 20C feet in length, the sizes of the beams and fore-and-afters are to be determined by linear interpolation.
	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.	ins.
6' 0"	5	7	5 ½	7	6	7	5	5	5 ½	5	6	5
8' 0"	6	7	6 ½	7	7	7	6	5	6 ½	6	7	6
10' 0"	7	7	7 ½	7	8	7	7	6	7 ½	7	8	7

RULE XII Carriers or Sockets.

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

RULE XIII Cleats.

Strong cleats at least 2 ½ inches wide are to be fitted at intervals of not more than 2 feet from centre to centre; the end cleats are to be placed not more than 6 inches from each corner of the hatchway.

RULE XIV Battens and Wedges.

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

RULE XV 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 of the standard weight and quality laid down by each Administration.

RULE XVI Security of Hatchway Covers.

At all hatchways in exposed positions on freeboard and superstructure decks ring bolts or other fittings for lashings are to be provided.

Where the breadth of the hatchway exceeds 60 per cent. 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.

RULE XVII Cargo and other Hatchways in the Freeboard Deck within Superstructures which are fitted with Closing Appliances less efficient than Class 1.

The construction and fitting of such hatchways, are to be at least equivalent to the standards laid down in Rule XVIII.

RULE XVIII Hatchway Coamings and Closing Arrangements.

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.

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.

RULE XIX Machinery Space Openings in Exposed Positions on Freeboard and Raised Quarter Decks.

Such openings are to be properly framed and efficiently enclosed 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.

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.

RULE XX Machinery Space Openings in Exposed Positions on Superstructure Decks other than Raised Quarter Decks.

Such openings are to be properly framed and efficiently enclosed 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. 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.

RULE XXI Machinery Space Openings in the Freeboard Deck within Superstructures which are fitted with Closing Appliances less efficient than Class I.

Such openings are to be properly framed and efficiently enclosed 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.

RULE XXII 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 ships in special trades is to be dealt with by each Assigning Authority.

RULE XXIII Companionways.

Companionways in exposed positions on freeboard decks and on decks of enclosed superstructures are to be of substantial construction. The sills of the doorways are to be of the heights specified for hatchway coamings (see Rules IX and XVILI). 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 ship's length from the stem, it is to be of steel and riveted to the deck plating.

RULE XXIV Ventilators in Exposed Positions on Freeboard and Superstructure Decks.

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 centre to centre, or by equally effective means. The deck plating at the base of the coaming is to be efficiently stiffened between the deck beams. The ventilator openings are to be provided with efficient closing arrangements.

Where such ventilators are situated on the freeboard deck, or on the superstructure deck within a quarter of the ship'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.

RULE XXV Air Pipes.

Where the air pipes to ballast and other tanks extend above 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.