3D Model — Orbit & Inspect
Anatomy of a Two-Way Radio
Antenna
Transmits and receives radio signals. Must be undamaged and fully extended for clear communication range.
PTT Button
Push-To-Talk — press and hold to transmit, release to listen. Half-duplex: only one person talks at a time.
Speaker / Microphone
Built-in speaker for receiving messages and microphone for transmitting. Hold radio upright near mouth for clarity.
Channel Selector
Selects the communication channel. All parties (dogger, crane operator, spotter) must be on the same channel.
Volume Control
Adjusts speaker volume. Set high enough to hear clearly over site noise but not so loud it causes distortion.
Belt Clip
Secures radio to belt or harness for hands-free carrying. Radio must be instantly accessible during lifting operations.
Battery Compartment
Houses rechargeable battery. Always start shift with a fully charged battery and carry a spare on site.
Purpose
Primary communication device between dogger and crane operator when hand signals or whistle signals are not practical.
Two-way radios are essential when:
- Distance between dogger and crane operator exceeds 50 metres
- Line of sight is obstructed by structures, loads, or equipment
- High ambient noise makes whistles ineffective (concrete pours, generators, multiple plant)
- Multiple cranes on site create potential for signal confusion
- Night work or poor visibility conditions
Radio Protocol for Crane Operations
Clear, standardised communication prevents incidents. Follow these rules every time:
- Always identify yourself: “Crane operator from dogger…”
- Use standardised commands: “Hoist up slowly”, “Boom down”, “Stop”, “All stop”
- Wait for acknowledgment before the crane operator proceeds with any movement
- “All stop” = immediate cessation of ALL crane movements — no exceptions
- Never use slang or abbreviations — clarity saves lives
- One instruction at a time — do not combine multiple commands
- Repeat back: crane operator confirms by repeating the command before acting
Standard Call Sequence
2. “Go ahead dogger, over”
3. “Hoist up slowly, over”
4. “Hoisting up slowly, copy”
Pre-Use Check
Before every lifting operation, verify radio functionality:
Pre-Use Checklist
- Battery is fully charged — check indicator
- Antenna is undamaged and securely attached
- Correct channel selected — confirm with crane operator
- Test transmit/receive — radio check with crane operator
- Volume adequate for site noise conditions
- Belt clip secure — radio won’t fall during operation
- Spare battery available on site
- Earpiece/headset working (if used in high-noise areas)
Do Not Proceed If
- Radio fails transmit/receive test with crane operator
- Battery below 50% and no spare available
- Antenna damaged or missing
- Excessive static or interference on selected channel
- Crane operator cannot clearly hear your commands
Radio vs Hand Signals
AS 2550 requires effective communication between dogger and crane operator at all times. Choose the right method:
| Condition | Hand/Whistle | Radio |
|---|---|---|
| Clear line of sight, <50m | ✔ Preferred | Acceptable |
| Distance >50m | ✘ Not reliable | ✔ Required |
| Obstructed view | ✘ Not possible | ✔ Required |
| High noise (>85 dB) | ⚠ Whistles may work | ✔ Preferred |
| Multiple cranes on site | ✘ Signal confusion risk | ✔ Required |
| Night / poor visibility | ✘ Not visible | ✔ Required |
Critical Rule
- If communication fails by ANY method — ALL crane movements must cease immediately
- Never continue a lift if you cannot communicate clearly with the crane operator
- A spotter with hand signals can supplement radio but NOT replace a failed radio
Site Radio Discipline
- Dedicated channel for crane operations — no general site chatter on lifting channel
- Keep transmissions short and clear — do not hold the PTT button while thinking
- Do not interrupt an active transmission — wait for “over” before responding
- Report any radio malfunction to the site supervisor immediately
- Radios must be carried at all times during lifting operations — never left on a bench
- In multi-crane sites, each crane/dogger pair should have a separate channel
- Emergency calls take priority — “All stop, all stop, all stop” overrides everything
Care & Storage
- Store in charging cradle at end of shift
- Keep dry — use waterproof pouch in wet conditions unless radio is IP-rated
- Do not drop — internal components are fragile
- Clean contacts regularly to maintain charging connection
- Replace batteries that no longer hold a full shift charge
- Report damaged radios — do not attempt field repairs
- Label radios with assigned crane/dogger pair for accountability