Why a factory needs task-level lux readings
A manufacturing floor might contain a dozen different visual tasks: loading raw material, operating a press, assembling sub-components, reading gauges, inspecting finishes and packing. Each needs a different amount of light, and getting it wrong has a direct cost in rework, rejects and accidents. A factory lighting survey measures every task area individually, so you know whether the operator at the end of line three has the light they need, not just what the hall averages.
Your legal starting point is regulation 8 of the Workplace (Health, Safety and Welfare) Regulations 1992. HSE guidance HSG38 Lighting at work sets out minimum average and minimum measured values by type of work, and also warns about stroboscopic effects where lighting flicker can make rotating machinery appear stationary. BS EN 12464-1:2021 provides the task-specific values that most manufacturers, auditors and insurers now work to.
Factory tasks and typical target values
Values vary by industry within BS EN 12464-1:2021, so the right figure for your plant depends on the processes involved. The table shows the kind of progression the standard uses.
| Type of task | Typical Em (lux) |
|---|---|
| Rough work, material handling, forging | 200 |
| General machine work, welding | 300 |
| Medium assembly | 300 to 500 |
| Precision machining, grinding, fine assembly | 500 to 750 |
| Detailed inspection and colour checking | 750 to 1000 |
| Dispatch packing | 300 |
| Plant rooms and switchgear | 200 |
Where products are colour-critical, such as printing, textiles, coatings or food grading, colour rendering is as important as lux, and we record the lamp type and condition alongside the reading. Use the required lux lookup to check a specific process.
What we look at on the production floor
- Machine and workstation task areas, measured at the working height of each machine rather than a generic desk height.
- Assembly benches and lines, including shadowing from overhead guards, gantries and the operator's own body.
- Quality control and inspection stations, where higher values and good uniformity are needed.
- Walkways and marked pedestrian routes through production, at floor level.
- Control panels, gauges and HMI screens, checked for readability and glare.
- Stroboscopic risk: we flag where rotating machinery sits under lighting that should be checked for flicker.
- Food production areas, noting fitting types and whether lighting suits hygiene and inspection needs.
Who asks for a factory lighting report
Factory lighting surveys are typically commissioned by H&S and operations managers reviewing risk assessments, by quality managers investigating defect rates, by insurers following a claim or risk visit, and by customers and certification bodies auditing suppliers. HSE inspectors may ask how you know lighting is adequate after an incident, and a dated survey is the clearest answer. If productivity is the concern, read our piece on whether poor lighting affects productivity.
How the visit works
- We review your process list and layout before the visit and agree which tasks need individual measurement.
- The engineer follows your site induction, PPE and permit rules, and works around running production.
- Readings are taken at each task area and on a grid across general production and circulation.
- Daylight is recorded separately or excluded, and we can return on a night shift where operations run around the clock.
Deliverables
- Task-by-task results with the BS EN 12464-1:2021 value applied and a pass, marginal or fail status.
- Uniformity figures for each zone and a plan showing measurement positions.
- Notes on lamp failures, dirty fittings, obstruction and flicker risk.
- Prioritised recommendations, starting with low-cost fixes such as cleaning and local task lighting.
Report turnaround is confirmed when you book.
Factory lighting surveys across London and the South East
We survey manufacturing sites across London, Hertfordshire, Essex, Kent, Surrey, Berkshire, Buckinghamshire, Bedfordshire, Cambridgeshire, Suffolk and Norfolk, from small workshops to multi-hall production plants.
Price
Factory and industrial lux surveys start from £320. Price depends on floor area, the number of distinct tasks and shift timing; multi-site programmes are priced on application. Every price is confirmed before booking. See pricing or the cost calculator.
Book a factory lighting survey
Send us your site address, approximate floor area and a short description of the processes, and we will come back with a price and survey date. Book your factory survey.
Frequently asked questions
What lux level does a factory need?
It depends on the task. BS EN 12464-1:2021 ranges from around 200 lux for rough work to 750 lux or more for precision assembly and detailed inspection, so we measure each task area separately.
Do you check for stroboscopic effects on machinery?
We flag areas where rotating machinery sits under lighting that could produce a stroboscopic effect, which HSE guidance HSG38 highlights as a hazard, and recommend follow-up where needed.
Can you survey during production?
Yes. We follow your induction, PPE and permit rules and work around running lines, including on night shifts if your plant operates around the clock.
Is a factory lighting survey useful for supplier audits?
Yes. A dated report showing measured lux at each task against BS EN 12464-1:2021 is clear evidence for customer audits, certification bodies and insurers.