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Power quality · P2-18

Electromagnetic Field (EMF) Assessment

Measurement of power-frequency magnetic and electric field levels around substations, busbars, cable routes and plant rooms, assessed against occupational and public exposure guidance and against the immunity limits of sensitive equipment nearby.

What this study establishes.

Magnetic flux density and electric field strength survey at defined heights and distances.

Comparison against ICNIRP reference levels for occupational and general public exposure.

Contour mapping around sources — transformers, busbars, cable risers, switchrooms.

Assessment against equipment susceptibility where sensitive apparatus is nearby.

Occupancy assessment identifying who is exposed, for how long, and at what level.

Mitigation options — separation, screening, conductor arrangement, or access restriction.

What the work covers.

Measurement of power-frequency magnetic and electric field levels around substations, busbars, cable routes and plant rooms, assessed against occupational and public exposure guidance and against the immunity limits of sensitive equipment nearby.

Field strength falls rapidly with distance and depends strongly on conductor geometry — trefoil arrangement produces a much lower external field than flat spacing at the same current. Where mitigation is needed, conductor arrangement is often cheaper and more effective than screening.

Deliverables

What lands in your inbox.

01

Magnetic flux density and electric field strength

Magnetic flux density and electric field strength survey at defined heights and distances.

02

Comparison against ICNIRP reference levels for occupational

Comparison against ICNIRP reference levels for occupational and general public exposure.

03

Contour mapping around sources

Contour mapping around sources — transformers, busbars, cable risers, switchrooms.

04

Assessment against equipment susceptibility where sensitive apparatus

Assessment against equipment susceptibility where sensitive apparatus is nearby.

05

Occupancy assessment identifying who is exposed, for

Occupancy assessment identifying who is exposed, for how long, and at what level.

06

Mitigation options

Mitigation options — separation, screening, conductor arrangement, or access restriction.

Methodology

How we run it.

01

Scope & data capture

We confirm the question the study must answer, agree the measurement or modelling points, and collect what the work depends on: layout showing sources and adjacent occupied or equipment areas; loading conditions during the survey, since field strength scales with current; details of sensitive equipment nearby, with its.

Agreed scope · Named lead engineer
02

Measurement & modelling

Engineers carry out the measurement and modelling on site and in software, under operating conditions representative of the problem rather than a single convenient snapshot.

Calibrated model · Raw records
03

Analysis against standard

Results are assessed against ICNIRP guidelines, IEC 62110, IEEE C95.6, with the assessment basis and any measurement uncertainty stated rather than implied.

Compliance position
04

Report & recommendations

You receive a signed engineering report with findings ranked by consequence, the reasoning behind each conclusion, and mitigation options costed so they can be acted on or deferred deliberately.

Signed report · Costed actions
Aligned standards

Assessed against the published limits.

ICNIRP guidelinesIEC 62110IEEE C95.6IEC 61786-1 and IEC 61786-2ICNIRP guidelinesIEC 62110IEEE C95.6IEC 61786-1 and IEC 61786-2
Notes & Queries

Common questions.

01

Typically in one of these situations: occupied space adjacent to or above a substation or major cable route; sensitive equipment — imaging, electron microscopy, metrology — near power plant; employee or tenant concern requiring a measured, documented answer. If none of these apply, the study is unlikely to be the right next step and we will say so.

02

To scope and run the work we need layout showing sources and adjacent occupied or equipment areas; loading conditions during the survey, since field strength scales with current; details of sensitive equipment nearby, with its susceptibility level if declared. Where any of it is missing we can establish it on site, which changes the scope rather than blocking the work.

03

Primarily ICNIRP guidelines, IEC 62110, IEEE C95.6, IEC 61786-1 and IEC 61786-2. The applicable framework depends on your connection agreement and jurisdiction, so we confirm which applies before measurement rather than after.

Ready to start the engagement?

Tell us about your site and the problem you are seeing. We come back with a fixed scope, a fixed fee, and a named lead engineer.