Inspection crews coming from building maintenance meet a different geometry on a bridge: the deck gives them nothing to anchor to, the drop may end in water or live traffic, and the farthest work positions sit under the girder where nobody on the deck can see them. The configuration order that works is fixed: decide the work face, then the equipment, and only then the monitored items.
Before entry: no anchor point? Rig a lifeline first
When the inspection truck arrives, check the outriggers first. Platform anchor points are limited to the positions the manufacturer provides — bridge railings, crash barriers and downpipes do not count. If nothing can be anchored under the bridge, run a horizontal lifeline along the inspection direction and clip workers to that line.
The effective lanyard length must not exceed 2 metres, as written in GB 6095-2021 and in the anti-fall inspection guides used on highway projects. If the geometry of the section makes 2 metres impossible, the anchor position moves — the lanyard does not get longer.
Platform stage: vertical climbing or lateral repositioning?
Climbing up and down within a platform is frequent height change. Under GB 23468-2025 clause 4.3.5.3 that calls for a self-retracting device or a rope grab, not a double-hook lanyard. Moving between anchor points under the girder follows clause 4.3.3.6: twin tail lanyards, swapping one tail at a time.
The two are not interchangeable. Double hooks on the climbing stage leave no continuous protection in mid-air; double hooks alone cannot cover large lateral moves once the lanyard length runs out. Getting this pairing wrong is the kind of error that only shows up when the fall happens.
Pier and bearing stage: leave what the deck cannot see to the equipment
Inside the box girder, on pier ladders and above the bearings, the safety officer on the deck can neither see the workers nor be heard by them. This is where a smart harness monitor earns its place: the Yunku multi-state harness monitor (SBM3000 series) mounts on the existing harness and recognises actions — unclipped hook, hanging empty, low-anchor misuse, lanyard dragging on the ground, long silence. A violation triggers a local buzzer for the wearer and a push to the management end.
The boundary is worth stating to any buyer: the monitor detects and alarms. It bears no load and does not lock hooks on the worker's behalf. The harness body still does the fall arrest.
Shift close-out: make the records match the work permit
Bridge inspection is scheduled by span or by day. At close-out, pull each worker's records and reconcile them with the work permit and the pre-shift briefing signatures; fill any gaps on the spot. Repositioning times are recorded as a side benefit, so afterwards you can see which section failed to clip in.
Check the harness body against GB 6095-2021 for its scope of use: wearer body weight plus carried load should not exceed 100 kg. Beyond that, assess separately.
What to ask a supplier for bridge work. Ask how the monitor behaves inside a box girder with no mobile signal, whether the buzzer is audible over traffic, and how records export against a work permit. For the harness itself, ask which standard the body is certified to — GB 6095 for projects inside China, EN 361 or ANSI Z359 where the destination market requires it.