429 Latticing and plating of struts 486 Runway crane clearances 430* Struts—minimum lattice bar dimen-sions 488 Outside crane equipage 431 Struts—angle of lattice bars 501 Grooving for drums and pulleys 432 Struts—batten plates 502 Ungrooved rope drums 434 Struts—spacing of bars and plates 507 Shaft keys, types of 435 Struts—rivets in columns 511 Sheave diameters 437 Effective span of members 521 Track wheels, avoid overhang 438 Effective depth of members 523 Track wheels, size and 444 Strength and ‘Z’ of members 524 Track wheels, diameters 445 Strength and ‘Z’ of plate girders 525 Track wheels, tread width 446 Plate girder flange rivets 540 Holding brakes on manual hoists 447 Distribution of wheel loads on plate girders 542 Pressure gauges, visible to driver 448 Plate girder flange section 543 Engine exhausts 449 Plate girder and stiffeners 544 Cylinder drain cocks, etc 451 Plate girder stiffeners at loads 548 Controls handy and easy 452 Plate girder stiffeners on both sides of web 811 Drilling

rule No No 453 Plate girder stiffener proportioning 812 Punching 456 Truss web tension members 813 Reaming 458 Camber of girders and trusses 814 Countersunk rivets 461 Joint splice plate, symmetry of 815 Riveting method 462 Joint splice plate, section of 817 Clearances for bolts 463 Web joints 818 Washers 464 Rivet shearing area 820 Shop painting 466 Rivet minimum pitch 821 Painting of inaccessible parts 467 Rivet maximum pitch 822 Field painting 468 Rivet edge distance 823 Painting, general 469 Rivets through packings 824 Bright or machined surfaces 470 Rivets in tension 825 Surfaces to be concrete protected 471 Rivet gauge lines 1006 No passengers on cranes 472 Rivet effective diameter 1007 Cabin, location, size, etc 473 Drainholes to prevent corrosion 1008 Warning devices 474 Brickwork bearing pressures 1009 Cabin protection in hot places 475 Concrete bearing pressures 1121 Driver, duties on leaving cabin 476 Pier tops 1122 Driver must lock crane against wind 477 Bearing pressures, eccentric 1301 Repair authorisation

rule No No 478 Piles 1302 Repair man, duties before repair 479 Foundations (bearing pressures) 1303 Repair man, to prevent parts falling 480 Track rail sizes

• It shall not be necessary to conform with rule 430, par 2. (174) Earth, clay, shale, sand, grit, powders, chippings, borings, spalls, punchings, clippings, swarf, offcuts or other aggregates or liquids shall not be used as counter or other balance, bias or operating weights unless encased in accordance with a design first submitted to and approved by the chief inspector. (175) Every portable counter, bias, balance or operating weight shall have permanently, clearly and distinctly stamped, engraved or embossed on them, its correct weight in pounds. (176) If a weight consists of detachable or demountable sections, each section shall be so marked with its own individual weight, only. (177) The figures and letters used in marking weights shall not be less than 1/ 2 an inch in depth. (178) No figures other than those stating the weight as mentioned in subsections (175) to (177) shall be marked on any portable weight. (179) Live counter, bias, balance or operating weights that are not of metal shall be encased, framed, or otherwise protected or fenced in a way approved by the chief inspector. (180) The chief inspector may, if the chief inspector considers appropriate, disallow the use of any such material or the chief inspector may require the use of an appropriate metal instead of it.