Cable Ladder Tray-Conduit Installation Safe Work Method Statement

For cable tray installation at 3 metres height, use elevating work platforms (scissor lifts or boom lifts) or mobile scaffold towers providing full guardrail protection and stable working surface. Scissor lifts work well for long straight tray runs allowing platform to traverse along installation route. Boom lifts provide better access for varying heights or routes requiring positioning over obstacles. Mobile scaffold towers suit confined areas where EWPs cannot access but require more setup time. Never use standard ladders as primary work platform for sustained tray installation - ladders only suitable for very brief access such as marking support locations. Platform selection must consider working height, work duration, building layout, and floor load capacity. Verify platform rated capacity accommodates combined weight of workers (typically 2 workers), cable tray sections (20-40kg per section), tools (10-20kg), and fixings. Minimum platform capacity is 250kg. Ensure platform equipped with full guardrails on all sides, mid-rails, and toe boards. Workers may still require fall arrest harness if platform guardrails are removed for access or if work requires leaning beyond platform edge. Train all operators on EWP safe operation including pre-start checks, emergency lowering procedures, and maximum wind speed limitations. Establish exclusion zones beneath EWPs preventing ground workers from struck-by hazards from dropped tray sections or tools.

Safe angle grinder operation for cable tray cutting requires multiple controls. First, select appropriate cutting disc - thin metal cutting disc specifically designed for steel, not grinding disc or masonry disc. Verify disc rated speed exceeds grinder operating speed typically 11,000 RPM or 80 m/s. Second, inspect disc before installation checking for cracks, chips, or damage - discard any damaged disc never attempt repairs. Third, install disc correctly ensuring proper seating on grinder flange and secure using spanner not just hand tight. Fourth, verify grinding guard covers maximum disc area with guard opening positioned away from operator's body. Fifth, secure cable tray being cut using clamps or vice preventing movement during cutting - never hand-hold work piece. Sixth, don appropriate PPE including safety glasses with side shields, full-face shield, hearing protection, cut-resistant gloves, and long sleeves. Seventh, position body to side of grinding plane so if disc breaks fragments project away from operator not toward body. Eighth, establish 2-metre exclusion zone preventing other workers approaching operating grinder. Ninth, start grinder and conduct test run at full speed for 30 seconds verifying disc runs true without vibration. Tenth, apply smooth steady pressure during cutting allowing disc to cut at designed rate - forcing grinder causes binding and disc breakage. Allow disc to reach full speed before contacting work and maintain speed during cut. If disc slows substantially, reduce pressure. Eleventh, complete cut allowing disc to stop completely before setting grinder down - never place operating grinder on surface. Twelfth, deburr cut edges using file removing sharp edges that could damage cable insulation. Dispose of metal off-cuts in designated container preventing trip hazards and cut injuries.

Cable tray support spacing depends on tray width, tray type, and cable loading. AS/NZS 3000 and manufacturer specifications provide guidance. For horizontal straight runs, typical support spacing is 1.5 metres for 150mm to 300mm wide ladder tray, 2 metres for 450mm to 600mm wide ladder tray, and 2.5 metres for wider ladder tray above 600mm. Basket tray and perforated tray may require closer spacing particularly with heavy cable loading. Vertical tray runs require supports every 3 metres maximum. Additional supports are required within 300mm of direction changes including bends, tees, and crosses. Support spacing must account for cable loading - fully loaded tray with maximum rated cable capacity requires closer spacing than lightly loaded tray. Calculate support load by summing tray weight plus maximum cable weight plus safety factor typically 1.5. For 300mm wide ladder tray weighing 6kg per metre supporting 30kg per metre cable loading, each 1.5-metre support carries (6kg × 1.5m) + (30kg × 1.5m) × 1.5 safety factor = 81kg or 800N load. Structural fixing must exceed this capacity with additional safety factor. For concrete structure, typical 12mm chemical anchor or expansion anchor provides 10-15kN capacity adequate for most tray applications. For steel structure, beam clamps or welded brackets designed for tray support loads. For masonry walls, verify wall thickness and mortar condition - older walls may require backing plates distributing load over larger area. When in doubt, conduct pull tests on sample fixings achieving 2.5 times design load without failure. Document support locations and fixing types in as-built records providing reference for future modifications or additions increasing tray loading.

Electrical clearances for cable tray installation near energised equipment follow AS/NZS 3000 and Safe Work Australia electrical safety guidelines. For 415V equipment which is most common commercial installation voltage, maintain minimum 1-metre clearance between cable tray and switchboard or electrical panel providing working space. For energised bus ducts or enclosed bus bars, maintain minimum 1-metre clearance from tray to bus system. Tray can reduce clearance to 0.5 metres if physical barrier such as permanent partition exists between tray and energised equipment. For work requiring closer approach than minimum clearances, arrange equipment isolation by authorised personnel before commencing tray installation. Never assume equipment is de-energised based on visual inspection or age - always verify using appropriate voltage detector and follow lock-out/tag-out procedures. When drilling for support fixings near electrical equipment, use electronic cable detector scanning walls and ceilings before drilling. Maintain minimum 300mm clearance from detected cables unless verified isolation is in place. If tray route must cross above energised equipment such as open-top switchboards, install solid tray covers preventing any objects from falling into energised equipment. Consider arc flash hazards when working near high-fault-current equipment - short circuits in 415V distribution can release substantial energy. Wear appropriate arc-rated PPE if working within flash protection boundary calculated for equipment. Coordinate with facility electrical personnel before commencing work in electrical rooms or areas with substantial electrical infrastructure. They can identify energised equipment, provide isolation if required, and brief on specific facility hazards. Document clearances maintained in installation records proving compliance with standards. If clearances cannot be achieved due to building constraints, consult electrical engineer for alternate routing or additional protection measures.

Preventing cable tray falls during elevated installation requires multiple controls working together. First, use two-person lifting for all tray sections ensuring controlled positioning without fumbling or loss of grip. Brief lifting team on communication protocol and coordinate all movements verbally. Second, before releasing manual hold on positioned tray, install temporary restraints securing tray to prevent falling. Use ratchet straps wrapping around tray and structural member, chains with hooks securing tray to supports, or temporary brackets holding tray in position during final securing. Never release tray assuming support friction alone will hold section - vibration from adjacent work or accidental contact can dislodge unsecured tray. Third, verify support brackets are properly installed and aligned before positioning tray. Misaligned supports may not capture tray correctly allowing it to slide off supports. Fourth, work from elevating work platform with guardrails providing stable work position. Workers on unstable access equipment such as ladders are more likely to lose control of tray during positioning. Fifth, use material lifts or hoists for particularly heavy tray sections reducing manual handling and providing controlled lowering onto supports. Attach lifting slings or chains to tray before hoisting, raise slowly to installation height, position over supports, and lower gradually onto supports before removing lifting equipment. Sixth, stage tray sections on work platform only after verifying platform capacity accommodates combined weight of workers and materials. Overloaded platforms create fall risks for both workers and materials. Seventh, establish exclusion zones beneath elevated tray work preventing ground workers from struck-by hazards. Mark boundaries with barrier tape and assign spotter monitoring zone preventing entry. Eighth, in high-wind conditions exceeding 15 metres per second (54 km/h), postpone elevated tray installation as wind loads on large tray sections can overcome restraints or cause worker loss of control. Ninth, brief all workers on dropped object prevention and consequences of falling tray sections including serious injuries and fatalities if workers are struck.

Working near energised electrical equipment that cannot be isolated requires enhanced controls beyond standard installation procedures. First, conduct comprehensive risk assessment identifying all energised equipment, voltage levels, available fault current, and potential contact scenarios. Document assessment including identified hazards and controls implemented. Second, establish minimum clearance distances based on voltage level - 1 metre for 415V, increasing for higher voltages. Mark clearances using barrier tape or physical barriers preventing workers approaching closer than clearance distance. Third, select cable tray materials and installation methods minimising contact potential. Use non-conductive tray support materials in high-risk areas or install insulating barriers between metallic tray and energised equipment. Fourth, use insulated hand tools rated for voltage present when working within 1 metre of energised 415V equipment. Tool handles must be rated to voltage level and regularly inspected for damage. Fifth, conduct arc flash risk assessment calculating incident energy level and flash protection boundary for equipment. If work occurs within flash protection boundary, wear appropriate arc-rated PPE rated for calculated incident energy typically minimum 8 cal/cm² for 415V equipment. Sixth, establish communication protocol with facility electrical personnel monitoring equipment operation during tray installation. If equipment faults or unusual operation occurs, stop work immediately and evacuate area. Seventh, limit workers in hazard area to minimum required - typically two workers for tray positioning with supervisor monitoring from safe location. Brief all workers on electrical hazards, rescue procedures, and emergency contact numbers. Eighth, use non-metallic measuring and marking tools preventing inadvertent contact between metallic tools and energised conductors. Ninth, work during facility low-demand periods when electrical loading is minimal reducing fault current magnitudes and arc flash energy. Tenth, consider alternate installation timing when equipment can be isolated during facility shutdown periods. Extra cost of delayed installation may be justified by elimination of electrical contact risks. Document all work near energised equipment including controls implemented, clearances maintained, and worker training provided.