A hose that carries enough air to a pneumatic rock drill is not automatically a safe hose assembly. If a pressurized hose ruptures or a coupling separates, the unsupported end can move violently. The correct control is a complete connection system: hose rated for the pressure and environment, compatible end fittings, positive means against accidental separation, suitable restraints or shielding where required, and a way to isolate or reduce pressure after a failure.
This page is a planning checklist, not a universal legal rule. The final arrangement must follow the drill and hose manufacturers, the mine or jobsite procedure, and the law that applies at the operating location. OSHA and HSE requirements illustrate the hazard, but they do not replace local engineering review.
Five controls that do different jobs
| Control | What it addresses | What it does not replace |
|---|---|---|
| Pressure- and service-rated hose | Burst, oil, temperature, abrasion and environment | Correct coupling or restraint |
| Positive locking at the tool/coupling | Accidental disconnection | Hose-failure protection |
| Hose restraint or shielding | Limits movement if a hazardous separation occurs | Isolation or excess-flow control |
| Source/branch safety device | Reduces released flow after certain failures | Correct hose routing and inspection |
| Isolation and depressurization procedure | Makes connection, service and replacement safer | Proper component selection |
OSHA's construction rule requires pneumatic power tools to be secured to the hose or whip by a positive means against accidental disconnection and requires a source or branch safety device for hoses over the stated inside-diameter threshold. HSE guidance separately notes that damaged flexible hoses can whip or snake dangerously and says hazardous flexible-hose failures should be restrained or shielded. Apply the provision that governs the actual site; do not copy one jurisdiction's threshold into a global specification.
Step 1: map every connection point
Draw the branch from the compressor or header to the drill:
- source or branch isolation valve;
- main hose and any reducer;
- filter, separator, regulator and lubricator;
- branch hose or whip hose;
- every coupling, nipple, pin, locking sleeve or safety clip;
- the rock-drill inlet.
The smallest component may be the flow bottleneck, while the weakest connection may be the safety bottleneck. Use the air-hose sizing guide for airflow and pressure-drop selection; use this page to control separation and hose-failure risk.
Step 2: freeze the selection inputs
Before ordering a hose assembly or restraint, record:
- maximum allowed working pressure and expected operating pressure;
- true hose inside diameter and total length;
- hose material compatibility with rock-drill oil, water, temperature and mine/quarry conditions;
- fitting type, bore, retention method and manufacturer;
- connection geometry and available anchor points;
- expected movement, abrasion, vehicle traffic and sharp edges;
- local rule for positive locking, restraints, shielding and excess-flow devices;
- inspection interval and replacement criteria.
Do not select a restraint only from the nominal hose size. Its length, attachment method, material, rating and permitted anchor points must match the specific assembly and manufacturer's instructions.
Step 3: install without creating a new weak point
The connection must be assembled by competent personnel using fittings intended for compressed-air service. The restraint should be attached to suitable points and positioned according to its manufacturer, with enough control to limit hazardous movement but without being wrapped around controls, sharp edges or hot surfaces.
Do not use a restraint to hold together incompatible or damaged couplings. Do not substitute ordinary wire, rope or an unverified clamp for a rated component. HSE guidance also stresses selecting hose for the temperatures, oils and pressures it will experience; a connection is not accepted merely because it survives a short static test.
Commission a new or changed hose assembly before pressurizing
A pre-use glance cannot prove that a newly assembled or modified connection is correctly specified. Use a separate acceptance check after a new installation, hose replacement, coupling change, reducer change, restraint replacement, abnormal pull, or repair. The purpose is to verify the complete connection path before it becomes the new inspection baseline.
| Acceptance point | Record | Pass condition | Hold or remove from service when |
|---|---|---|---|
| Source and branch | Isolation-valve identity, branch device, direction of flow, pressure rating and applicable site rule | Isolation is accessible; required devices are installed in the approved orientation and match the branch | The branch cannot be isolated, a required device is absent, or its rating and function are uncertain |
| Main hose and end fitting | Hose manufacturer/type, inside diameter, length, working-pressure and temperature rating, end-fitting identity | The hose and fitted ends are traceable, compatible with the service and free from assembly damage | The hose is unrated, incorrectly fitted, damaged, or the end attachment cannot be verified |
| Coupling and positive lock | Both mating halves, bore, connection type, locking pin/sleeve/clip and any adapter | The intended halves fully engage and the specified lock prevents accidental separation | Parts only appear to fit, the lock is missing or damaged, or an improvised adapter or clamp is used |
| Restraint or shielding | Restraint type, size/rating, permitted attachment points, installed position and manufacturer instruction | The restraint matches the assembly and is attached only to approved structural points without interfering with controls | Size or rating is unknown, attachment is improvised, wires are damaged, or placement creates a new snag or control hazard |
| Whip hose and tool inlet | Whip-hose specification, rock-drill model, inlet connection and transition components | The tool inlet, whip hose and coupling are mechanically compatible and do not create an unverified restriction | Thread, seat, bore, adapter stack or tool-side retention is uncertain |
| Routing and movement envelope | Normal drill movement, hose support, bend radius, pull direction, traffic, edges and pinch points | The full operating movement can occur without tensioning the coupling or restraint | The hose can be pulled apart, crushed, driven over, sharply bent or trapped during normal drilling |
| Inspection baseline | Assembly date, verifier, photos, component references, defects corrected and next inspection point | The accepted configuration is identifiable for future pre-use checks and replacement | No one can prove which components or arrangement were accepted |
Use an ACCEPT / HOLD / REMOVE decision
- ACCEPT: every required component, rating, mating interface, lock, restraint, route and isolation control is verified under the manufacturer and site procedure. Record the accepted configuration before use.
- HOLD: the assembly appears undamaged, but a rating, applicable rule, approved attachment point or supplier instruction is missing. Do not pressurize it until the evidence is closed.
- REMOVE FROM SERVICE: damage, a failed lock, mismatched coupling, improvised attachment, inaccessible isolation or another stop-work condition is present. Quarantine and replace or correct the assembly.
Do not use an uncontrolled pull test, pressurized disconnection or improvised proof test to “confirm” the connection. Any functional or pressure test must follow the hose, coupling, restraint and site commissioning procedure, with the area controlled and personnel clear of the potential movement path.
Copy-ready hose-assembly acceptance record
Record: site and drill ID; branch ID; rock-drill model and inlet; hose type, inside diameter, length and rating; end-fitting and coupling references; positive-lock method; restraint or shielding reference; approved attachment points; isolation and branch-device status; route hazards; inspection photos; verifier and date; decision; open corrective action. Attach this record to the RFQ, commissioning file or maintenance history when the assembly is replaced.
Step 4: pre-use inspection
| Check | Pass condition | Remove from service when |
|---|---|---|
| Hose cover and body | No cuts, exposed reinforcement, blistering or severe abrasion | Structural damage or uncertain rating is found |
| Ferrule/end fitting | Secure, no slip, cracking or deformation | Movement, corrosion or wrong fitting is visible |
| Coupling lock | Fully engages and cannot separate accidentally | Lock, pin or sleeve is missing or damaged |
| Restraint | Correct type, intact and attached at approved points | Kinked, corroded, frayed, incorrectly sized or improvised |
| Routing | Protected from vehicles, edges, pinch points and trip hazards | Hose is crushed, sharply bent or unsupported in a hazardous path |
| Isolation device | Identified, accessible and functional | The branch cannot be safely isolated and depressurized |
Inspect the assembly before use and after a coupling change, hose replacement, abnormal pull or impact. Isolate and depressurize before correcting any defect.
Plan the Hose Route Before Pressurizing or Moving Between Holes
A safe hose assembly can still become unsafe when its route changes. The route must keep fittings and restraints out of tension, protect the hose from traffic, edges and pinch points, preserve the designated access and escape path, and allow the drill or air leg to complete its approved movement without dragging a coupling. Treat the route as a controlled work-state decision: prove it while isolated, monitor it under use, and recheck it after every move or abnormal pull.
This module owns the heading-level hose route and between-hole repositioning decision. It does not replace the hose-rating, coupling, restraint or branch-device checks elsewhere on this page, and it does not define a universal lockout sequence. The site procedure and exact equipment instructions control isolation, depressurization, restraint, exclusion zones and who may handle a service line.
Route-release matrix
| Work state | Evidence to establish | READY condition | HOLD / STOP condition |
|---|---|---|---|
| 1. Mark the movement envelope | Planned collar, drill and air-leg travel, operator position, steel-change space and the route people use to enter or leave the work area | The complete approved movement can occur without the hose entering a pinch point, being pulled tight or blocking access | The route depends on a person standing in the movement path, crosses the designated escape route, or cannot cover the planned positions without loading a connection |
| 2. Trace the service line | Branch/isolation point, hose sections, couplings, oiler or treatment equipment, supports, crossings and the tool inlet | Every section and connection can be identified and inspected; isolation remains accessible from the approved position | A connection is hidden, the isolation point is obstructed, or the line shares an uncontrolled vehicle or material-handling path |
| 3. Control crossings and contact | Vehicle routes, sharp edges, pooled water, heat sources, falling-material zones, doors and temporary floor crossings | The hose is rerouted or protected by a site-approved method without creating a trip, crush or snag hazard | The hose can be driven over, pinched, cut, overheated, buried, or struck during normal work |
| 4. Set slack without creating loops | Minimum bend requirement from the hose supplier, expected pull direction, supports and the full tool movement | Enough controlled slack remains for movement, while loose loops and unsupported weight cannot snag people or load the coupling | The hose is taut at any planned position, sharply bent, coiled in a walkway, or supported by the coupling, restraint or tool inlet |
| 5. Dry-run while isolated | Competent crew moves the depressurized setup through each planned position and observes the hose, coupling, restraint, controls and access path | No contact, tension, snag, sharp bend, blocked access or control interference appears | Any person must pull the hose by a coupling, step over an uncontrolled line, enter a pinch zone or improvise a support |
| 6. Controlled start | Area control, accessible isolation, accepted connection system and observation of the line as pressure is introduced under the approved procedure | The assembly remains seated, stable and clear with no leak, movement or route change | A hose, fitting or restraint moves unexpectedly; a leak appears; or the route changes as the line pressurizes |
| 7. Move to the next hole | Stop state required by the site procedure, new collar and movement envelope, line condition and confirmation that no one will handle a pressurized connection or enter its potential movement path | The new position passes the same route checks and the service line remains within its approved condition | The move requires correcting a kink, trapped section, connection, restraint or uncertain line condition without the required isolation and depressurization |
| 8. Abnormal pull, impact or route change | Event location, hose/fitting/restraint condition, isolation result and inspection of every affected connection before restart | The approved inspection closes the event and records the accepted configuration | Damage, slippage, unknown rating, lost traceability or doubt about a coupling, fitting, restraint or isolation device remains |
Use a three-state route decision
- READY: the identified hose assembly, route and full movement envelope pass the isolated dry run and the controlled start; the accepted route is recorded.
- HOLD FOR ROUTE CHANGE: the assembly itself is serviceable, but a crossing, pinch point, access conflict, lack of support or insufficient controlled slack must be corrected and checked again before use.
- STOP, ISOLATE AND INSPECT: an abnormal pull, impact, unexpected movement, leak, trapped hose, damaged protector or uncertain connection state occurs. Do not treat a visual repositioning as proof that the assembly remains acceptable.
Copy-ready heading hose-route record
Site / heading / date: Drill and air-leg identity: Branch and isolation-point identity: Air-hose sections, ratings and connection references: Planned collar positions and tool movement envelope: Operator access / escape path: Vehicle, material-handling and floor-crossing controls: Edges, heat, water, pinch and falling-material checks: Support points and controlled slack: Isolated dry-run result: Controlled-start observation: Between-hole move state required by site procedure: Abnormal pull / impact / route-change findings: Decision: READY / HOLD FOR ROUTE CHANGE / STOP-ISOLATE-INSPECT Verifier / corrective action / next inspection:
Attach this route record to the hose-assembly acceptance record already described above. If the drill model, hose length, coupling, branch location, support arrangement or working pattern changes, review the affected route again instead of carrying the earlier approval forward automatically.
Stop-work conditions
- unknown hose or coupling pressure rating;
- missing positive locking where required;
- improvised clamps or attachments not designed for compressed-air service;
- damaged hose, ferrule, coupling or restraint;
- no safe isolation point;
- a hose routed where vehicles or equipment can pull it apart;
- uncertainty over the applicable site rule.
RFQ information for a hose and connection package
Send the rock-drill model and inlet, required airflow and pressure, hose ID and length, oil/water exposure, temperature, connection type, branch layout, local standard, expected movement, and photos of both attachment points. Start with the Pneumatic Rock Drills collection, review the active YT28 air-leg rock drill as a configuration example, check air-inlet compatibility, and request a configuration review.
FAQ
Is a whip check the same as a positive-locking coupling?
No. A positive lock helps prevent accidental separation. A restraint is intended to limit movement if a hazardous separation or failure occurs. The final system may also need isolation or excess-flow protection.
Can I reuse a restraint after a hose failure?
Do not assume it remains acceptable. Remove it from service and inspect or replace it according to the manufacturer's instructions and the site's incident procedure.
Does every country use the same hose-size threshold?
No. Regulatory thresholds and accepted devices differ. Use the law and site standard for the operating location.