# Equipment service report

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### CLIENT

Braithe Estuary Partnership Estuary House, Vardenne Quay Braithe BR3 4LN

| Job reference | KAL-ESR-4471 |
|---|---|
| Date of visit | 29 January 2026 |
| Engineer | R. Tarbert |
| Instrument | Kestrel 400 turbidity analyser |
| Location | Vardenne Quay pumping station |
| Service interval | Twelve months |

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### Reported fault

Intermittent baseline noise on channel 2, reported by the Partnership on 21 January. The analyser had been running without attention since the annual service in January 2025.

### Work carried out

The flow cell was removed, stripped and cleaned, and the pump tubing set replaced. The optical window was found to be lightly fouled on the inner face; it was cleaned rather than replaced, and should be inspected again at the next visit. The analyser was recalibrated against the two-point standards and left running on channel 2 for an hour before the site was handed back. The completed worksheet is bound in as page 2 of this report.

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Kirkhollow Analytical Laboratories Ltd

Service worksheet

| Job reference | KAL-ESR-4471 |
|---|---|
| Instrument serial | GK-2214-77 |
| Engineer | R. Tarbert |
| Date | 29-January 2026 |

READINGS

CHECKS AND

Flow cell condition on arrival Flow cell pressure after service Zero drift over 30 minutes

Span recovery against standard Lamp hours at service Result

Calibration certificate SR-4471/2 Analyser left in service on channel 2. Optical window to be inspected at the next visit.

TIME ON SITE

+

Arrived

Left

Chargeable time

Next service due

RECEIVED BY

| Name | M. Cairney |
|---|---|
| Position | Duty operator, Vardenne Quay |
| Date | 29 January 2026 |

FIELD SERVICE

Fouled, inner face 2.4 bar 0.003 mg/l 99.4 per cent 8,140 Pass

29 January 2026, 09:15

29 January 2026, 13:40

4 hours 25 minutes

January 2027

~~.

Engineer's signature

Service worksheet KAL-ESR-4471

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## Parts fitted

### Part

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Pump tubing set

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Flow cell O-ring, 12 mm

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Inlet filter, 40 micron

### Code Quantity

PT-114 1 OR-0912 2 IF-4004 1

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## Declaration

The work described in this report was carried out to the standard set out in the service agreement. The analyser was left in service and calibrated. The next annual service falls due in January 2027.

| Engineer | R. Tarbert |
|---|---|
| Countersigned | Dr A. J. Prosser |
| Report issued | 2 February 2026 |