Obstruction detection and safe stops/reversals.
Prove that people and vehicles are protected. Use standard test objects and intrusion scenarios to verify obstruction detection and auto-reverse/stop behaviors, with stopping distances tied to control logic (342) and safety circuits (343). Check human-factors cues and night conditions (353, 357). Document repeatable results, track defects, retest after fixes, and store evidence for SAT/authority reviewers (638, 717). Include upward links to this section and the chapter hub. For UAE approvals, see SIRA Bollards (UAE). If readers need practical context during installation, see What to Expect and the Installation Guide.
Important: This is a general guide. For live projects we develop a tailored
Method Statement & Risk Assessment (MS/RA) and align with authority approvals (e.g., SIRA) where in scope.
635.1 Test objects & sizes
Use standard cones, bars, and dummies. Objects simulate HVM bollard real risks.
Select surrogate objects that represent wheels, bumpers, and a child-height surrogate. Calibrate dimensions and hardness so the system’s safety edge and photo-eye responses are consistent. Keep a master list of approved test pieces in the Commissioning Tools kit (529) with photos and serials.
Document each object’s size/weight and the position it occupies in the lane (centerline versus edge near the clear-gap). Include sketches so witnesses reproduce placements in the SAT/Witness Procedure (638).
| Aspect | What matters | Where to verify |
|---|---|---|
| Representativeness | Height/width & hardness of surrogates | Commissioning Tools |
| Placement | Within clear-gap and capture paths | Safety Circuits (343) |
| Repeatability | Template photos & coordinates | Evidence Capture Standards |
635.2 Obstruction detection
Place objects; verify stop/reverse. Detection keeps crash rated bollard lanes safe (343).
Prove each detector path: induction loops, photo-eyes, and safety edges. For each, record trigger thresholds and zones, and confirm annunciation per Alarm Philosophy (536). If approvals apply, note SIRA evidence in the log.
635.3 Auto-reverse/stop actions
Measure reaction and stopping distance. Actions prove HVM bollard control quality (342).
When an obstruction is detected, measure controller reaction time and whether the system performs a controlled stop or auto-reverse, per the defined control logic (342). Cross-check that the action is prioritized correctly in the state machine & interlocks (526) and that events appear in the fault/health logs (541).
635.4 Safe stopping distances
Confirm distances within target bands. Distances protect crash rated bollard users (536).
Establish acceptance bands for stopping distance versus approach speed and load. Record multiple runs and average results; flag any outliers beyond the acceptance band. Tie results to alarm handling (536) and visible safety signalling (353) so users understand status during stops.
635.5 Human factors checks
Observe cues, delays, and signage (353). Human checks reduce HVM bollard misuse.
Assess signage clarity, beacon timing, and driver/pedestrian conspicuity. Verify instructional latency on the HMI & local controls (524) and check for nuisance alarms that could desensitize operators.
635.6 Night/low-vis conditions
Repeat with low light and glare (237, 546). Night tests validate crash rated bollard signalling.
Repeat all tests after dusk or with simulated glare to confirm signal brightness, acoustic limits (546), and legibility of signs per Sightlines & Signage (237). Check retroreflectivity on markings and that any night auto-dimming still meets visibility needs.
635.7 Repeatability evidence
Run multiple cycles; compare logs. Repeatability stabilizes HVM bollard acceptance.
Execute a fixed sequence (e.g., 10 cycles per test case) and compare change-of-state logs and timestamps. Store documented evidence (431) under the submission index (917) with exact build numbers (change control & versioning, 537).
635.8 Defect list & fixes
Record defects, owners, dates (639). Fixes restore crash rated bollard readiness.
Log each failure in the snag list (639) with root cause, owner, and due date. Use photos/video and a short NCR (719) note when acceptance criteria are missed. On safety-critical items, require a re-witness before closure.
635.9 Retest outcomes
Show pass evidence post-fix. Retests close the HVM bollard loop.
After implementing fixes, rerun all affected cases and attach “before/after” data to the authority submittals (717). Update the evidence pack (716) and mark sign-offs in the witness procedure (638).
Related
External resources
- NPSA — Hostile Vehicle Mitigation (HVM)
- ASTM F2656 — Vehicle impact performance of perimeter barriers
- FEMA 426 — Reference Manual to Mitigate Potential Terrorist Attacks Against Buildings
635 Obstruction & Intrusion Tests — FAQ
What counts as a “pass” for obstruction detection?
The system must reliably detect standard surrogates (cones, bars, child-height dummy) in each defined zone and initiate the correct action (stop or auto-reverse) within the acceptance reaction time, with events recorded in the controller logs.
How many cycles should we run to prove repeatability?
A practical baseline is 10 cycles per case (day and night). If results scatter near the acceptance band, increase to 20 cycles and investigate sources of variance (sensors, alignment, environmental factors).
Do we need to retest after software or wiring changes?
Yes. Any change affecting logic, wiring, or safety devices requires targeted retests and updated evidence tied to the change control/version ID before SAT sign-off.
What gets filed for authorities such as SIRA?
Include the signed witness sheets, logs, time-stamped photos/video, and the change/version references inside the submission index. Reference any NCR closures and retest outcomes.