Gold and Diamond Mine Security: Bring the Interview to the Field

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A gold or diamond operation can lose substantial value through small, repeated incidents. By the time an inventory review identifies a serious shortage, investigators may be reconstructing weeks of movements, handovers, and access.

Consider a hypothetical diamond operation that discovers a $1 million discrepancy over 60 days. The security team now faces several questions: when did the losses occur, which handling points were involved, and what records or witnesses can establish what happened?

A later examination cannot restore missing surveillance footage, recover an undocumented handover, or preserve a witness’s fading memory.

For mining security leaders, the practical question is how to bring a structured investigative response closer to the first concern.

VIPRE’s AISIS and VASIS offer portable, microphone-based examination workflows for trained investigative professionals. Their operational value is the ability to bring equipment to an appropriate interview location and document responses without attaching physiological sensors to the person being interviewed.

A Different Workflow for Remote Operations

Gold and diamond security programs operate across processing plants, sorting facilities, secure storage areas, transport routes, and remote sites. An examiner’s availability and the location of suitable facilities can affect how quickly a concern receives attention.

A conventional polygraph records physiological responses through equipment attached to the body, including breathing sensors, skin-conductance sensors, and a cardiovascular component. Professional examination procedures also require preparation, question review, recording, and interpretation.

Polygraph equipment can be transported. A mine may be able to accommodate an examiner in a suitable on-site room. The accurate distinction is that portability of the instrument does not eliminate the requirements of the examination environment. The British Polygraph Society describes a private setting reasonably free from distractions. A medically sterile room is not the requirement.

AISIS and VASIS use microphone-based voice acquisition. That removes the need to fit cuffs, breathing tubes, or skin sensors to the interviewee.

For a trained examiner working across several operational locations, that difference can simplify equipment preparation and movement between suitable interview spaces.

It does not make a noisy processing floor an appropriate examination setting. Privacy, clear audio, understandable questions, and control of interruptions remain important.

British Polygraph Society examination guidance

Readiness in Minutes, With Time Reserved for Proper Examination

VIPRE describes its portable workflow as capable of being deployed and made ready in under 15 minutes in suitable conditions.

That is an operational readiness estimate. Actual preparation depends on the equipment configuration, examiner experience, available space, and recording conditions.

Readiness is also different from completion. A responsible examination still requires time for:

Establishing the purpose and lawful basis of the session.
Reviewing relevant facts and preparing clear questions.
Explaining the process and obtaining required consent.
Recording usable responses.
Reviewing the material and documenting follow-up.

The operational advantage is a simpler path to beginning the interview. It should never become pressure to rush the person, shorten necessary preparation, or treat an initial indication as a finished finding.

Likewise, there is no sound basis for saying that every polygraph requires an hour of equipment setup. A complete polygraph appointment includes much more than attaching equipment, and its duration should not be confused with setup time.

Responding Before a Discrepancy Becomes a Larger Investigation

Return to the hypothetical $1 million diamond discrepancy.

An operation that waits until its periodic reconciliation may need to review two months of personnel movements, production records, access logs, and material transfers.

A more responsive security program establishes clear escalation points when concerns first arise. These might include:

A discrepancy between recorded and received material.
A broken seal or unexplained custody gap.
Access to a restricted area outside an authorized task.
Conflicting accounts of a specific handover.
A report of attempted diversion or unauthorized removal.

Where legally permitted, a trained examiner using AISIS or VASIS can bring a structured examination capability to an appropriate location near the operation.

The examination can focus on a defined event and timeframe. A broad accusation such as “Did you take anything?” may leave the subject matter unclear. Question preparation should establish what material, action, location, and period are actually being examined.

The resulting record can support decisions about what to investigate next. Any response requiring closer review should be checked against independent evidence.

An indication does not establish theft. An absence of an indication does not clear a person or explain missing inventory.

On-Call Capability Requires More Than Portable Equipment

A portable system is most useful when the organization already knows how it will be used.

Before deployment, mining security leaders should establish:

Who is qualified and authorized to conduct examinations.
Which circumstances justify a session.
Where private, suitable interviews can take place.
How language and interpretation needs will be handled.
Who may access recordings and examination records.
How findings will be reviewed and corroborated.

This makes the equipment part of an organized response rather than an improvised reaction.

Where lawful, an on-call examiner may help a team address a specific concern closer to the time it arose. That is a practical benefit worth evaluating. It is not a guarantee that an examination will prevent a loss or identify the person responsible.

Training and Staffing the Program

Training requirements affect how an operation develops and maintains its examiner capability.

VIPRE’s system offerings include 40-hour Basic Examiner Certification training allocations. Its training addresses system operation, question formulation, interpretation, and professional examination practice. Buyers should confirm the current course and requirements for the system they intend to use.

For comparison, the British Polygraph Society lists partner-school basic polygraph instruction at 400 hours, with courses delivered over 10 to 17 weeks. These are different training pathways and qualifications. A shorter course does not, by itself, establish equivalent competence or superior performance.

For a remote mining operation, the staffing discussion should include course availability, examiner suitability, continuing development, supervision, and review procedures.

Training is the beginning of an accountable program, not a substitute for one.

Routine Employee Checks Depend on the Law

Operational convenience does not establish legal permission.

A mine should not assume it can introduce daily voice stress checks simply because the equipment is portable or uses no attached sensors.

In the United States, the Employee Polygraph Protection Act generally restricts private employers’ use of lie detector tests. The Department of Labor explicitly includes certain voice-analysis and AI-based deception technologies within that concern. The limited ongoing-loss investigation exemption permits qualifying polygraph examinations under specified conditions; it does not create a general exemption for voice stress testing.

International operations need jurisdiction-specific advice covering employment law, privacy, consent, labor agreements, and examination practices.

The correct starting point is an authorized use case, followed by a suitable procedure and qualified personnel.

AISIS and VASIS Within a Layered Mining Security Program

AISIS provides VIPRE’s AI-assisted examination workflow, including synchronized waveform, audio, and video review. VASIS remains a current, valued examiner-led platform.

Both belong within a wider security program built on reliable records and independent investigation.

Neither replaces:

Material accounting and reconciliation.
Access control and surveillance.
Documented custody and transport procedures.
Physical searches or inspections conducted under lawful policy.
Evidence preservation and professional investigative judgment.

Voice-related stress indications require interpretation. Stress can have explanations unrelated to deception, and no indication should serve as the sole basis for an accusation or employment decision.

For gold and diamond operations evaluating portable examination capability, the useful demonstration is a practical one: show how the examiner prepares, captures responses, records observations, reviews the session, and identifies evidence-based follow-up.

Bring the examination capability closer to the operation. Keep every conclusion tied to the evidence.