First, the obligations with dates on them
| Obligation | What it requires | Since | Instrumentation it implies |
|---|---|---|---|
| MHSA reg 8.10.1.2 | Underground diesel TMM must automatically detect pedestrians and warn both operator and pedestrian | 21 Dec 2022 | Proximity detection on machines and wearable tags on people |
| MHSA reg 8.10.2.1 | Diesel TMM must detect other TMM and, absent action, automatically retard to safe speed then brake — fail-safe | 21 Dec 2022 | EMESRT Level 9 intervention controls integrated with machine braking |
| MHSA reg 16.7 | No person underground without an intrinsically safe device giving last known location; surface operations too where risk assessment shows it | 28 Mar 2025 (GN 6052, GG 52388) | IS-certified person-location tags and an underground reader network |
| OEL amendment (GN 6053) | Respirable crystalline silica limit lowered from 0.1 to 0.05 mg/m³, with other airborne-pollutant limits reduced | 28 Mar 2025 | Real-time dust and gas monitoring alongside personal sampling |
| MHSC milestones | 95% of silica measurements under 0.05 mg/m³ and equipment noise ≤107 dB(A) by Dec 2024; ≤104 dB(A) and no new hearing-loss cases by Dec 2034 | 2014 / 2024 summits | Continuous noise and dust records per area and per machine |
| GISTM | Performance monitoring, trigger-action response plans and disclosure for tailings facilities | Extreme/very high consequence Aug 2023; all others Aug 2025 | Piezometers, displacement, pond level and freeboard, seepage — telemetered |
| GN 704 + water-use licence | Clean and dirty water separation, containment, and licence-condition monitoring of mine water | 1999 (GN 704) | Flow at every transfer, quality at every discharge, dam levels |
The underground working face and haulages
This is where the two dated regulations meet. Trackless mobile machinery — LHDs, dump trucks, drill rigs, utility vehicles, anything diesel-powered and unconstrained by rails — must detect pedestrians and other machines and, under 8.10.2.1, act on its own if nobody else does. Around the same headings, occupational hygiene lives: respirable dust at the face against the new 0.05 mg/m³ silica limit, diesel particulate from the fleet, and the gases — carbon monoxide, nitrogen dioxide, methane where the orebody carries it — that the ventilation plan exists to dilute. The monitoring stack is wearable tags on people, proximity detection on machines, and fixed gas and dust sensors at the split; the guides are collision prevention under 8.10, which detection technology, and occupational hygiene monitoring.
Person location — shafts, levels and the whole underground
Regulation 16.7 changed the question from "who is underground" to "where is each person, last known, right now". Lamp-room tally boards answer the first; only a reader network with intrinsically safe tags answers the second, and the regulation requires the device to be IS-rated because it is carried into workings that may hold a flammable atmosphere. The design questions — zone-level versus precise location, reader placement along travelling ways, how the record feeds rescue — are the subject of our 16.7 person-location guide. Surface operations are not exempt where a risk assessment identifies slope failure or inrush hazards: a pit worker can go missing too.
The ventilation network and fans
Ventilation is simultaneously the mine's largest electricity consumer and its life-safety system, which is why monitoring it earns twice. Air velocity and volume at working places and splits, gas concentrations, differential pressure across controls, wet-bulb temperature for heat stress, and fan status and power together tell you whether the air is going where the plan says — and whether you are moving more of it than the people underground need. Ventilation-on-demand, where fans and regulators follow occupancy from the person-location system, is the operational payoff; our ventilation monitoring guide and the VOD case study cover both halves.
Open-pit walls, benches and haul roads
Surface mines swap gas and confinement for scale and gravity. Slope stability is monitored with prisms, radar and, increasingly, satellite interferometry, feeding trigger levels that move people and machines off a bench before it moves; the same 8.10 collision logic applies to haul trucks and light vehicles on ramps, at intersections and around excavators; dust from haul roads and blasting is an occupational-hygiene and community issue at once; and blast monitoring (ground vibration and air overpressure) is the record neighbouring landowners will ask for. Fleet management systems from the major OEMs run the production side; the safety telemetry — proximity, fatigue, dust, vibration — is the layer beside them.
Shaft and winder
The winder is the mine's single point of failure for people and rock, and its regulation is the most prescriptive in the book: rope condition, brake performance, over-wind and over-speed protection, and the examination records that go with them. Condition monitoring — brake temperature, motor current signature, drum and headgear vibration, rope-tension trends — adds the early warning between statutory examinations, and the shaft's own environment (airflow, gas, water make) belongs in the ventilation and water pictures above and below.
The processing plant — crushers, mills, conveyors, flotation
Once ore is on surface the mine becomes a heavy continuous plant, and the loss physics inverts: few critical rotating assets, rare stoppages, catastrophic cost per stoppage. Crusher and mill bearings, girth gears, conveyor drives and idlers, slurry pumps and flotation blowers carry the condition-monitoring weight — vibration and motor current signatures on a short list of assets. Conveyors deserve their own line: they are the artery from face to plant, and belt drift, idler failure and fire risk are catchable. Our predictive maintenance for mining and conveyor monitoring guides cover the assets; the production-environment map places the plant among its industrial cousins.
Tailings storage facilities
Since Brumadinho, tailings monitoring is governed by GISTM, whose deadlines have passed for every consequence class, and whose core requirement is performance monitoring against trigger levels set by the engineer of record. Piezometers for pore pressure, inclinometers and survey for displacement, the phreatic surface, pond level and freeboard, seepage flow and quality — telemetered and buffered so a rising trend is seen the night it starts, not at the next manual round. The tailings monitoring guide covers the instrument set and the trigger-action response plan; the regional context includes the 2025 Kafue incident in Zambia that made the case for continuous monitoring without needing a South African example.
Mine water — dewatering, return water, discharge
A mine handles more water than ore. Dewatering volumes, return-water balances from the tailings facility, stormwater kept clean and separate from process water under GN 704, and any discharge or seepage under a water-use licence with parameters that read like a chemistry syllabus. Flow at every transfer point and quality at every discharge are the core instruments; acid mine drainage adds pH and conductivity on seepage paths and receiving streams. The regulator-facing record is built the same way as for any environmental discharger — continuously, at the boundary — and our water monitoring scenario map carries the discharge regimes in full.
Surface infrastructure and power
Substations, compressors, refrigeration plants, gensets and pump stations run the mine and fail quietly. Mains presence and generator state matter more in South Africa than anywhere: load shedding on a mine is a ventilation event, a dewatering event and a winder event at once, and the record of what ran on what power during the outage is the record the inquiry reads. Compressed-air and refrigeration plants are also where energy monitoring pays back fastest — the same per-asset energy measurement our OEE and energy solution applies in factories.
Coal-specific: gas, spontaneous combustion, intrinsic safety
Coal mines add methane, the hazard that makes intrinsic safety a design requirement rather than a preference: every electronic device carried or installed in a hazardous area must be certified so it cannot release enough energy to ignite the atmosphere. Continuous methane and carbon monoxide monitoring at the face and in returns, with trip logic to power and machines, is the core; carbon monoxide trends in goafs and stockpiles are the early warning for spontaneous heating. Our mining connectivity and IS guide covers what certification means for the sensor and network hardware.
Quarries, aggregates and small operations
A quarry is an open-pit mine with a crusher and a weighbridge, and it inherits the same obligations at smaller scale: TMM interactions at the crusher feed and loading points, dust at the primary crusher and haul roads, blast monitoring for neighbours, slope inspection, and a plant whose crusher and screens are the only assets worth monitoring individually. The practical entry point is usually dust and the crusher — one exposure record and one condition-monitoring node — before the fleet-safety layer.
The map on one table
| Site area | Dominant hazard | First sensor | Regime |
|---|---|---|---|
| Underground face & haulages | TMM–pedestrian and TMM–TMM collisions; dust and gas exposure | Proximity detection with intervention; fixed gas/dust at the split | MHSA 8.10; OEL regulations |
| Person location (whole underground) | Missing persons in an emergency; blind rescue | IS-certified tags + reader network | MHSA 16.7 |
| Ventilation network | Insufficient air; gas accumulation; heat; energy waste | Velocity + gas + differential pressure; fan power | Ventilation plan; OELs |
| Open-pit walls & haul roads | Slope failure; vehicle interactions; dust; blast vibration | Slope radar/prisms; proximity on fleet; dust and blast monitors | MHSA 8.10; hygiene; community |
| Shaft & winder | Winder mechanical failure; over-wind | Brake temperature, vibration, motor current | Winding-equipment regulations |
| Processing plant | Catastrophic rotating-asset failure; conveyor fire | Vibration + current on mill, crusher, conveyor drives | Production economics; fire safety |
| Tailings facility | Wall failure; seepage | Piezometers, displacement, pond level and freeboard | GISTM; dam-safety regime |
| Mine water | Licence breach; acid drainage; unaccounted water | Flow at transfers; pH/conductivity at discharge | GN 704; water-use licence |
| Surface infrastructure & power | Silent utility failure; load-shedding cascade | Mains presence, genset state, compressor/refrigeration health | Continuity; energy cost |
| Coal workings | Methane; spontaneous heating | Continuous CH₄/CO with trip logic; IS-certified everything | MHSA; IS certification |
| Quarries & small operations | Crusher-area dust; TMM at loading points | Dust at the crusher; crusher condition node | MHSA at smaller scale |
Three rules that hold across every row
- The dated obligation goes first. Regulation 8.10 and 16.7 carry commencement dates that have passed; the silica limit halved in 2025; GISTM deadlines have all fallen due. Where an inspector can ask for a record by regulation number, that area is instrumented before the ones that merely save money.
- Detect, warn, intervene — then record. The EMESRT logic behind 8.10 generalises: a sensor that only alarms has done a third of the job. Trigger levels, an automated or procedural response, and a timestamped record are what turn monitoring into a control — for a proximity system, a tailings piezometer or a methane sensor alike.
- Certification is part of the specification. Intrinsic safety where the atmosphere may be flammable, and the engineer of record's trigger levels on a tailings facility, are not features to add later. A sensor that cannot legally be carried into the working, or a reading nobody has set a threshold for, is a stranded asset with a datasheet.
Where to go deeper: mining solutions (the delivery) · MHSA 8.10 collision prevention · detection technologies compared · 16.7 person location · occupational hygiene · ventilation · tailings · connectivity and intrinsic safety · MHSA safety case study.