Welding Fume Extraction Planner

Worked example

STATIC — not a live result

Regular indoor MIG/MAG on mild steel for 150 minutes at a fixed workpiece, with movable LEV available, people nearby and assessed mechanical ventilation. The planner issues a source-capture control route with ordered actions for a competent person to assess.

R-FUME-EX

Welding fume extraction planner

Planning estimate

Control route to assess

Entered assumptions

F-01ProcessMIG/MAG

F-02LocationIndoors

F-03FrequencyRegular — most shifts

F-04Task duration150 min

F-05WorkpieceFixed / large

F-06Source captureMovable LEV available

F-07People nearbyYes

F-08General ventilationMechanical, assessed

F-09MaterialMild steel

Ordered actions to assess

Treat exposure control as required: HSE states all welding fume can cause lung cancer, however small the amount of welding.
Plan movable LEV with the hood placed close to the arc and repositioned as work progresses — swing-arm hoods only capture when workers keep them in position.
Assess residual fume even with capture in place — where capture is incomplete, HSE expects RPE in addition to LEV.
Exclude unprotected people from the welding area, and check general ventilation clears fume where others work.
Record the assessment and maintain the controls: LEV needs thorough examination and testing, and RPE needs a management programme.

Planning support only — this route is a starting order for a competent assessment, not a completed one.

Method

M.2026-08-20.1

No numeric score is computed. The planner reads the nine entries against a fixed set of decision rules drawn from the HSE welding-fume guidance in the source register, then issues a control route to assess: ordered actions, the facts you selected, and any unresolved inputs.

Any welding process selection carries a control requirement — HSE states all welding fume can cause lung cancer.
An enclosed or restricted location, or an unresolved location, stops the automated route outright: a competent assessment is required before any equipment choice.
Outdoors, LEV is not treated as effective capture; HSE guidance calls for RPE and for people nearby to be considered.
Regular indoor work routes to source-capture engineering control: on-torch extraction is preferred for MIG when you say it is available, movable LEV carries a correctly-repositioned-hood action, and a movable workpiece can route to an extracted bench or booth.
Occasional work, less than weekly and under 60 minutes, surfaces HSE’s sporadic-welding route as something to assess — RPE plus good general ventilation — and is never presented as an exemption.
Where capture is unavailable or unknown, or residual fume remains, an RPE and competent-assessment action is added.
People nearby (or unknown) add an explicit exclusion, protection or ventilation action; coated or unknown material adds a contaminant assessment before work.

In the worked example, regular indoor MIG/MAG at a fixed workpiece with movable LEV routes to source-capture engineering control — the static card above shows the ordered actions exactly as the presenter issues them.

Limits & stop conditions

T-01

Decision support only: nothing here measures exposure, selects a specific RPE class or completes an assessment — a competent person does that.
STOP — an enclosed or restricted space, or an unresolved location, ends the automated route; the record says so instead of issuing actions.
Unknown entries never improve the route; they are listed on the record as unresolved inputs to close out.
The issued route is a starting order for a competent assessment, not a completed one.

Welding fume extraction planner

Worked example

Method

Limits & stop conditions

Source register