🌿 Sampling of sea water for chemical and physical testing from tidal areas (estuaries), the coastal zone up to 5 km from the shore and the open sea — location of sampling points according to a mixing model derived from salinity, temperature, oxygen, turbidity or chlorophyll fluorescence, vertical and horizontal profiles, open-ended tube samplers on a non-metallic line, pumps and automatic samplers, frequency within the tidal cycle; not for microbiological and biological samples, PN-ISO 5667-9

Environment PN-ISO 5667-9

Overview

WHAT THE STANDARD COVERS. Scope from the PKN catalogue card of PN-ISO 5667-9:2005 (Polish version), in full (our translation): “Guidance is given on the principles for designing programmes and techniques of sampling and on the preservation and storage of sea water samples from tidal areas (e.g. estuaries, tidal inlets, coastal sea waters and the open sea). It does not apply to sampling for microbiological or biological analyses”. We read the text of the standard in the iTeh sample of ISO 5667-9:1992 (French version): from the foreword through the introduction and Clauses 1–4 up to and including 5.2.1.2. Outside the sample remains the whole rest of the standard after 5.2.1.2 — including 5.3, to which 4.2.5 refers on automatic samplers — and the annexes: A (normative) and B (informative), named in the foreword. The sample has no table of contents, so we do not know which clauses follow.

ACCORDING TO THE TEXT OF ISO 5667-9:1992 (Clauses 1–4, 5.1–5.2.1.2). The standard was prepared by ISO/TC 147 “Water quality”, subcommittee SC 6 “Sampling”; it belongs to the ISO 5667 series and is to be read together with ISO 5667-1 (sampling programmes), ISO 5667-2 (techniques) and ISO 5667-3 (preservation and handling of samples). Scope (1): principles for designing programmes, sampling, preservation and handling of sea water samples from tidal areas (e.g. estuaries, tidal inlets), coastal zones and the open sea; it does not apply to samples for microbiological and biological analyses (for microbiology — ISO 8199). Objectives (1.1–1.4): quality characterisation (variability in space and time, influence of climate, biology, water movement and man), quality control (long-term measurements at defined locations against objectives such as bathing, protection of aquatic life, desalination, cooling), special investigations (causes and effects of changes, pollution sources, fate of pollutants — with the reservation that mortality can have natural causes and gradual accumulation of pollutants often goes unnoticed) and effects of structures (dams, jetties, bridges, dykes, harbours, waste discharges). Definitions (3): spot sample, samples forming a vertical profile (a series at various depths at one location — several locations are needed to characterise the whole water body), samples forming a horizontal profile (at one depth at various locations; in a channel — along or across it, in coastal waters and the open sea — on a grid), composite sample. Containers (4.1): many substances occur in sea water at very low concentrations, so contamination and losses by adsorption must be prevented, taking into account the ionic strength, considerably higher than in other natural waters; where the sample may interact with the container — glass or other inert materials; fragile containers are avoided at sea. Equipment (4.2): below the surface, manual immersion of the container, opening and closing it once filled is sufficient; the bottle is rinsed several times with the water to be sampled; the operator wearing plastic gloves samples ahead of the platform in open water — e.g. from the bow of a boat drifting with the wind or current. Open and surface samplers are not recommended for sampling below the surface because the surface film may contain significant concentrations of certain compounds; the surface microlayer is sampled with special samplers, but in practice only qualitatively. Closed tube samplers are recommended for spot samples or series at a given depth; most are made of PVC and may contaminate — samplers lined internally with PTFE, “aged”, with silicone rubber or PTFE O-rings are recommended, without internal rubber tensioners and external metal springs. Types: air-displacement (depth limited by pressure and current — mainly estuaries) and open-ended (lowered on a hydrographic line, which for trace metals and hydrocarbons must be non-metallic; closed by a messenger, water pressure or electromagnetically; before closing the sampler is left for 5 min to “acclimatise”; the messenger must be plastic-coated); in strong currents or at great depth the line inclines, and the actual depth is calculated from the length of line paid out and its angle; near the bottom — special samplers. Peristaltic or centrifugal pumps with rotors that do not introduce contamination, with the tube on a non-metallic line at a distance from it, flushed before sampling — for chemically stable dissolved and suspended substances, not for gaseous and volatile compounds. Automatic samplers take samples at constant time intervals, often together with in situ probes and telemetry. Sampling locations (5.1): the distribution is set after a detailed preliminary survey at many points, so that reliable interpolation between them is possible; care must be taken that adjacent stations do not sample the same water mass — this happens when the distance between them does not exceed the distance travelled by the water in the tidal cycle; sampling from boats, ships, hovercraft, helicopters, and in a shallow estuary — from the shore, a jetty, dyke or bridge. Tidal areas (5.1.1): a preliminary “mixing model” from measurements of temperature, conductivity (salinity), oxygen, turbidity or chlorophyll fluorescence, e.g. by a longitudinal survey of salinity; then samples according to the heterogeneity found — in the horizontal profile e.g. every 2 salinity units (UNESCO, 1981), in the vertical — near the surface, at mid-depth and near the bottom; an effluent plume can be traced with fluorescent dyes, and the correlation of salinity with the concentration of a dissolved substance shows its gain, loss or conservative behaviour and the share of individual discharges. Coastal zone (5.1.2): bays, harbours and other waters up to 5 km from the shore — likewise a mixing model, and for some substances, e.g. nutrients, separate studies. Open sea (5.1.3): variability smaller but significant at current boundaries and in upwelling zones — profiles of salinity, temperature and density; in a homogeneous layer no more samples are taken than analysis and statistics require. Frequency (5.2): variability from seconds to years (season, rainfall, light, tides, plankton); for characterisation — under non-exceptional conditions, at the same tidal phase or over the whole cycle, for an instantaneous picture — quickly over the whole grid; with intermittent discharges — so as to capture periods of discharge and no discharge (5.2.1.1); for control — under non-exceptional conditions, in tidal and coastal zones several samples over the tidal cycle, at a frequency depending on the parameters determined, and occasional samples when conditions depart from normal (5.2.1.2).

STATUS (card as of 03.10.2026). The card of PN-ISO 5667-9:2005 (Polish version, published 04-11-2005, 15 pages, price group H) has no “Withdrawn” header: Health, Environment and Medicine Sector, KT 119 Water Quality — Basic Problems, ICS 13.060.10 and 13.060.45, “Introduces: ISO 5667-9:1992 [IDT]”; the card has no “Replaces” field. In the iTeh catalogue (read on 03.10.2026) ISO 5667-9:1992 has the status “Published” and stage 90.93 “International Standard confirmed” (completed 29.08.2026).

HOW MANY LABORATORIES AND IN WHAT FORM (copy of the accreditation scope database, data up to 17.09.2026, read on 03.10.2026). The number 5667-9 appears in 5 records at 5 laboratories: AB 177, AB 362, AB 646, AB 794, AB 1156 — everywhere “PN-ISO 5667-9:2005”. In the current PCA documents (read on 03.10.2026, issues from 17.02.2026 to 16.07.2026) the number appears in 5 items of the same 5 laboratories. The “Laboratories” tab (“PN-ISO 5667-9”) shows the same 5 laboratories — checked with the tab query on the production server labcoda.pl on 03.10.2026.

WHAT THE LABORATORIES TEST (items in PCA). All items are “sampling for chemical and physical testing” (at AB 646 “physical and chemical”). As a separate subject “sea water” — AB 646 (with temperature (-4–35) °C according to in-house instruction I-29) and AB 1156 (with temperature (0.0–40.0) °C according to PN-77/C-04584). At AB 362 a separate sampling item with PN-ISO 5667-9 for water, with temperature (0.0–50.0) °C. At AB 177 and AB 794 the standard stands in one cell together with the standards for sampling lakes and reservoirs (PN-ISO 5667-4), rivers and streams (PN-EN ISO 5667-6) and groundwater (PN-ISO 5667-11) — AB 177 excludes clauses of the river standard and the groundwater standard, AB 794 only of the groundwater standard; for the marine standard neither has exclusions. No item is suspended.

WHERE A SEEMINGLY CORRECT RESULT IS EASY. With equipment: according to the standard a PVC sampler is a potential source of contamination, and for trace metals and hydrocarbons the line must be non-metallic and the messenger plastic-coated (4.2.3) — contamination from these sources leaves no trace in the result; in choosing the container the standard requires taking into account the much higher ionic strength of sea water than of other waters (4.1); an open sampler passed through the surface film picks up compounds present there at high concentration (4.2.2). On closing: the standard requires leaving the sampler for 5 min before closing to “acclimatise” to the surroundings (4.2.3) — omitting this pause leaves no trace in the result. On depth: in a strong current the length of line is not the depth — it must be calculated from the angle (4.2.3). With a pump: the standard rules out pump sampling for gaseous and volatile compounds (4.2.4) — a result of such a determination from a pumped sample has no basis in the standard. In the plan: adjacent stations closer than the distance travelled by the water in the tidal cycle sample the same water mass, and samples from different tidal phases without correction of position do not give an instantaneous picture (5.1, 5.2.1.1).

WHAT WE DO NOT GIVE. We have not read the rest of 5.2, 5.3 and the following clauses or the annexes, so we do not give requirements on the duration of sampling or on preservation and storage of samples, which the PKN card names in the scope. Nor do we state whether and where the standard speaks of safety of work at sea. We do not give requirements of regulations on monitoring of marine and transitional waters — we have not read the texts of the acts for this entry.

Method principle

Sampling of sea water is planned after a preliminary survey of the mixing model of the water body (salinity, temperature, oxygen, turbidity or chlorophyll fluorescence), and stations are placed in vertical and horizontal profiles so that interpolation between them is possible and adjacent ones do not cover the same water mass. Samples are taken by manual immersion of the container, with open-ended tube samplers on a non-metallic line, with pumps or automatic samplers, made of materials that do not introduce contamination and do not adsorb substances present at very low concentrations, and the frequency is matched to the tidal cycle, seasons and the purpose of the programme.

Applications

• Sea waters of tidal areas (estuaries, tidal inlets), the coastal zone up to 5 km from the shore and the open sea — samples for chemical and physical testing (1, 5.1)
• Programmes of quality characterisation, quality control, special investigations (sources and fate of pollutants) and assessment of effects of structures (1.1–1.4)
• Does not apply to samples for microbiological and biological testing (1)
• Water and sea water — sampling for chemical and physical testing in the accreditation scopes of 5 laboratories in PCA

Key parameters

Standard

Standard number

PN-ISO 5667-9:2005

Title (PL)

Jakość wody — Pobieranie próbek — Część 9: Wytyczne dotyczące pobierania próbek wód morskich

Title (EN)

Water quality — Sampling — Part 9: Guidance on sampling from marine waters

Step-by-step procedure

1. Objective and preliminary survey

   Define the objective (characterisation, control, special investigations, effects of structures); preliminary survey at many points and mixing model. PN-ISO 5667-9:2005 current (PKN card as of 03.10.2026).

2. Location of stations

   Vertical and horizontal profiles according to heterogeneity; spacing greater than the distance travelled by the water in the tidal cycle; in the coastal zone up to 5 km — likewise.

3. Choice of equipment

   Manual immersion, tube sampler on a non-metallic line or pump (no gases or volatiles); inert materials, gloves, sampling ahead of the platform.

4. Sampling

   Rinsing the container with the water sampled; sampler 5 min before closing; with an inclined line, depth from the angle and length of line.

5. Frequency

   Under non-exceptional conditions, at the same tidal phase or over the whole cycle; with intermittent discharges — during and without discharge; occasional samples under unusual conditions.

Required equipment and apparatus

Health and safety (OHS)

• Sampling from boats, ships, hovercraft and helicopters requires rules of safe work on water — the part of the standard read does not contain them
• Fragile containers are not used at sea (4.1)
• Work with hydrographic lines and heavy samplers in strong currents — risk of injury and loss of equipment

Frequently asked questions