Questions we are asked before an order
Answered directly, including the ones where the honest answer is “it depends, tell us more”. Where a question concerns standards, we say what we can confirm and what we cannot.
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What is a confined space monitoring system?
A confined space monitoring system does three things at once: it measures the atmosphere inside the space, it tracks who is inside and for how long, and it manages the permit that authorises the entry. A gas detector alone does only the first. The distinction matters because most confined space fatalities involve a hazard that was detected but not communicated to the person who needed to act on it.
What gases are monitored inside a confined space?
Oxygen, carbon monoxide, hydrogen sulfide and combustible gas (LEL) cover the majority of industrial confined spaces and are the standard four-gas configuration. Specific spaces need additional or different sensors: sewer networks are dominated by hydrogen sulfide and methane, chemical vessels may retain solvent vapour or process-specific toxics, and inerted or purged vessels require oxygen measurement as the primary parameter. Tell us the space and its process history and we will confirm the sensor set.
Why do I need to sample at the workface rather than at the entrance?
Because a confined space atmosphere is not uniform. Vapour accumulates at the bottom of a vessel, hydrogen sulfide collects in low-lying sections of a sewer, and a detector held at the manhole reads a different atmosphere from the one a worker meets two metres further in. Pump-suction sampling with an extendable hose lets the sample be drawn from where the person will actually be working.
Does the equipment need a network connection to work?
No, and this is a deliberate design choice rather than a limitation. Inside the space, the internal unit communicates with the gas detector and wristbands over LoRa 2.4 GHz, so detection and local alarm continue in the signal dead zones typical of steel vessels and tunnels. The external unit handles the mobile uplink for remote notification. Where a plant cannot send data outside its own network, the platform can be deployed on-premise.
How does the system know how many people are inside?
Through the entry point. Personnel carry an RFID or Bluetooth wristband and register in and out at the entry monitoring device, which maintains the headcount and reconciles it against the permit. Over-occupancy and overtime alerts are raised automatically. In long tunnels, positioning along the run is combined with the entry log so that supervisors know not only how many are inside but where they are.
What happens if there is no mobile signal inside the space?
The alarm still reaches the entrant. The wristband and the internal unit both alarm locally on a threshold breach, and they communicate with each other over LoRa rather than through the mobile network. What is lost without a signal is the remote notification to the safety office, not the warning to the person in danger. For long runs, a cabled data bus carries detection, video and positioning along the tunnel.
Is a cable trench or a utility tunnel a confined space?
Yes — these are linear confined spaces: long, narrow, poorly ventilated, with few exits and a section that may be far from the access point. They defeat monitoring arrangements designed for compact vessels, because a unit at the entrance cannot see, hear or sample the far end. This is the case our cascaded linear monitoring system is built for, with coverage up to 1,000 m along a wired data bus.
Can confined space permits be handled electronically?
Yes, and doing so fixes a specific failure. Paper permits record that a signature was collected; they do not record that a briefing happened, what the atmosphere readings were at the time, or who was actually inside. An electronic workflow captures permit approval, pre-job briefing with audio and video, entrant authorisation, atmospheric records, alarm history and tool accountability as the work happens, with everything time-stamped and exportable.
What does a confined space monitoring system cost?
It depends on four variables rather than on a price list: the number of entry points, whether the spaces are compact or long tunnels, the sensor configuration (standard four-gas or custom), and whether you need public-cloud or on-premise deployment. Send us the space types, the number of points or units, and the standard you are audited against, and we will propose a configuration and a budget range rather than a list price that will not survive contact with your site.
What is the difference between a gas detector and a confined space monitoring system?
A gas detector measures the atmosphere at one location and signals locally. A monitoring system also manages the people and the process: who entered, under what permit, when, for how long, with what vital signs, and which tools went in and came out. Most incidents involve the second category of failure — a hazard that was measured but not acted on — which is why the equipment that detects is not the same as the equipment that controls.
What is low anchorage and why is it so dangerous?
Low anchorage is a fall-protection configuration where the lanyard is attached to a point at or below the worker's feet. It converts a short arrest into a long fall, increases the arrest forces on the body, and removes the clearance the system was designed around. It is dangerous because it is invisible from the ground: the harness is worn, the lanyard is connected, and the arrangement is wrong in a way only the wearer can see.
How does a smart safety harness detect that it is not being worn correctly?
A multi-axis posture sensor on the harness, combined with edge computing on the device, classifies the harness state — high anchorage, level, low, ground, suspended, free-fall, idle — and identifies specific violations such as a harness that is not worn at all, a hook that is not connected, or a lanyard anchored below the feet. Because the classification runs on the device, detection continues where there is no network coverage, which is exactly where steel erection and tower work take place.
Can a monitor be retrofitted to harnesses we already own?
Yes. The harness-mounted monitor is designed to fit existing full-body harnesses and can be installed by your own team, which is how most plants begin — a single crew and one harness type, before wider rollout. Where crews use several attachment devices, a multi-state monitor recognises pole straps, secondary lanyards, double hooks, fall arresters and self-locking devices on one control unit.
How do we keep an exclusion zone controlled without a permanent fence?
With an active boundary rather than a physical one. A battery-powered millimetre-wave radar unit scans a full 360° horizontally to 6 m, unaffected by darkness or weather, and a Bluetooth reader verifies whether the person entering is carrying an authorised tag. Anyone without a tag triggers a local alarm and a remote notification. Because it runs on battery with a magnetic base, the boundary can follow the work front rather than being installed once.
How do I know whether equipment is suitable for my hazardous area?
Match the equipment marking against your zone classification, and get the confirmation in writing. Our harness monitors and fence units are available in intrinsically safe versions rated Ex ib IIC T4 Gb. Send us your zone diagram and the equipment list you are considering, and we will confirm suitability rather than leave it as an assumption — an assumption here is difficult to reverse after installation.
What is the difference between ATEX, IECEx and Chinese explosion-proof certification?
They are different certification schemes addressing the same problem. ATEX is the European framework, IECEx is the international scheme, and Chinese certification is issued against national standards. Equipment certified under one scheme is not automatically accepted under another, although the underlying protection concepts (intrinsic safety, flameproof enclosure, and so on) are common. Tell us the scheme your site is audited under and we will confirm which certificates and test reports apply, and what additional documentation your authority may require.
Which fall protection standard applies to us — GB, ANSI or EN?
It depends on your jurisdiction and your insurer. GB 6095-2021 is the Chinese national standard and is what our supplied harnesses comply with as standard. ANSI Z359 applies in the United States and EN 361 in Europe. Where a project specifies ANSI or EN, raise it at enquiry stage so the applicable configuration and documentation can be confirmed before ordering rather than after delivery.
How long does deployment take?
Harness monitors retrofit to the existing harness in minutes and can be fitted by your own team; a fence unit is placed on its magnetic base with no wiring at all. Larger rollouts — issuing monitors across crews, or fencing several zones — are configured to order. Platform configuration, alert rules and user roles are set up with your safety team, usually remotely.
Can the system integrate with the safety platform we already run?
Interfaces for third-party platform integration are provided across the product range, and on-premise deployment is available where data cannot leave the plant network. Many operators use our monitoring equipment as the field layer beneath their existing platform, or run our platform and integrate the two where the existing system covers a different part of the process.
What documentation is supplied with the equipment?
Commercial invoice, packing list, certificate of origin, English manuals and labelling, third-party test reports for the relevant product line, and explosion-proof certificates for intrinsically safe models. Where your local authority requires additional documentation, tell us at enquiry stage and we will confirm what we can provide before you commit to the order.
No attendant can watch a confined space job continuously — what equipment automates monitoring and alarms?
Four device classes, each covering one failure of human attendance. A gas detection ball at the workface measures oxygen, carbon monoxide, hydrogen sulfide and combustible gas continuously and alarms locally on a threshold breach. A smart wristband on each entrant tracks heart rate and blood oxygen and carries an SOS call. An entry control unit at the access point registers who went in and keeps the headcount. A camera adds the visual record. On our LSM3000 monitoring station the external unit shows gas data, personnel status and video on one screen at the entrance, so the attendant sees what is changing inside without leaving the entry point.
Do we need a portable gas detector, a gas detection ball, or both?
Both, because they answer different questions. A pump-type portable detector draws samples point by point from the locations inside the space before entry — diffusion portables at the opening only read the air around the instrument. The detection ball is for during the job: it sits near the workface with a built-in pump, uploads readings automatically every 15 minutes instead of relying on hand-copied records that break at shift change, and carries a camera so the attendant can watch and correct the workface remotely. Judge entry with the portable; monitor the job with the ball, with both feeding the display at the entrance.
Can a harness be anchored to scaffold tubes or guardrails?
No. GB 23468-2025 rules out anchor points that are moving, low-strength, insecure or sharp-edged — guardrails, scaffold ledgers, pipework and cable trays included. Anchor to a concrete beam or column, a primary structural steel member, or a calculated anchor point; where none exists, rig a lifeline. The smart harness monitor checks that hooks were connected correctly — it cannot certify that the member takes the load.
How do workers stay tied off across a long rooftop run?
It comes down to two habits, not the device: connect first, then disconnect — confirm the new hook is secured before releasing the old one, with no gap in between. Plan the anchor spacing along the route before work starts; where anchors are scattered across a roof or steel structure, add a horizontal lifeline or rail so there is always a point to hook onto along the whole run.
How does a smart harness know a worker is above 2 metres?
It does not read a 2 m number — it reads air pressure. A high-precision barometric sensor measures relative height to roughly 0.6 m, with temperature compensation built in. A baseline is calibrated at the starting position before work; once the worker rises more than 2 m above it, monitoring switches to elevated-work mode. Calibration belongs in the pre-shift routine — a wrong baseline counts flat walking as climbing, or misses low-level work.
Is a smart harness monitor the same thing as a fall arrester?
No, and the difference decides what you are buying. A fall arrester takes over once a person is falling: it limits the drop distance and absorbs the arrest force, and it is the last line of protection — judged on how fast it locks and on whether it has been tested to GB 6095-2021. A harness monitor works before the fall: it watches whether the hook is connected at all and whether the anchorage sits where it should. Our monitor recognises an unconnected hook, anchorage below the feet and a dragging lanyard, alarms on the spot with sound and light, and files the event — while taking no part in load bearing. So it is not a choice between the two: configure the equipment to GB 23468-2025 first, then add monitoring to govern how it is used. Leave out either half and the other delivers less than it should.
Which positions on a site need fall protection monitoring?
Four positions cover it, and a smart harness monitor takes on the three that concern how a person moves at height. Edges and openings — where falls start most often — are handled by area-isolation alarms that trigger when someone crosses the boundary. Suspended platforms and scaffolds are where equipment worn on the person matters, because the working surface moves and a ground camera cannot see inside the basket: our multi-state harness monitor (SBM3000 series) confirms that both hooks are connected and that the anchorage sits above the attachment point. Ladders and towers are the stretch with the most re-anchoring, where GB 23468-2025 clause 4.3.5.3 points to a fall arrester or self-retracting lifeline and the monitor confirms no re-anchoring step is skipped. Access points are a separate category: they record who went in and how many people are inside.
How do we turn harness violation records into a dashboard?
Do not lift the alarm log onto the board unchanged — a crew dashboard tracks three things and only three. Who: a violation ranking by person and by crew, which is possible only because the monitor (SBM3000 series) is bound to a named wearer and files each event with name, employee ID, time and location; without identity you can show a total but cannot hold anyone to it, and records must match a named person to be retrievable under GB 23468-2025 at inspection. Fixed or not: incident, correction and re-check set side by side, with repeat violations of the same type flagged — that pattern usually points at anchorage layout or training rather than at the individual. When: time distribution read week by week, which shows which shifts run hot and is more useful than a raw count. The management platform filters and exports by crew, so no separate report is needed; set up the crew structure and the named ledger at handover and every board has an owner.