ATEX approval, IP65 ingress protection, and the right stainless steel grade only count as compliance when they match the exact model, the exact hazardous zone, and the exact process fluid. This guide explains how to read the certification set behind low flow meters — using the Micro Coriolis mass flow meter SH-CMF-FE and the Coriolis mass flow meter SH-CM from Silver Automation Instruments as reference products — and how to verify ATEX scope, CE marking, IP rating, wetted materials, and connection types before an order is released.

Low flow metering is a small-number discipline: 2 sccm of gas, 40 g/h of liquid, a few drops per minute. The measurement itself is rarely what stops a project. What stops a project is documentation — a certificate that does not name the ordered model, a Zone 2 approval used in a Zone 1 area, or an enclosure rating that does not survive the plant's washdown routine. This article is written for chemical, pharmaceutical, and petrochemical buyers, process engineers, and procurement teams who are past the discovery stage and are now evaluating or executing a purchase.

Why Compliance Becomes the Deciding Factor in Low Flow Meter Projects

Compliance is not a single document. In low flow instrumentation it is a chain: a certificate, a product list inside that certificate, the standards the certificate references, the validity window, and the region in which the certificate is recognised. A break in any link produces a meter that measures accurately but cannot be accepted by the plant's safety or quality function.

Three failure modes account for most compliance rework in small-line metering:

• Model-to-certificate mismatch. The supplier holds an ATEX certificate, but the specific model or the specific process connection variant is not listed on it.
• Zone mismatch. The certificate scope covers Zone 2, while the installation point is classified as a more severe zone. Zone 2 describes an area where an explosive gas atmosphere is not expected during normal operation and, if it occurs, exists only for a short period.
• Environment and material mismatch. The ingress protection level or the wetted material does not match the cleaning regime or the fluid, for example a 304 stainless steel sensor in a chloride-bearing stream, or a standard enclosure in a frequent hose-down area.

For buyers in the Evaluation and Execution stages, the practical consequence is that compliance verification must happen before the purchase order, not during factory acceptance testing. The checklist described later in this guide is designed to be run in that order.

Industry Background: Compliance Pressure Inside a Growing Low Flow Market

Three market movements explain why certification questions are raised more often in low flow metering than in general flow measurement.

First, the installed base is large and regionally concentrated. The global flow meter market was valued at USD 10.64 billion in 2024, with Europe holding the largest regional share at over 35%, according to Grand View Research. Europe is also the region where ATEX and CE documentation is routinely audited, so the certification requirement arrives with the quotation.

Second, the low flow segments are growing faster than the general market. Thermal flow meters, which are widely used for low gas flow rates, reached USD 1.73 billion in 2024 and are projected to reach USD 2.9 billion by 2035, according to Market Research Future. Coriolis flow meters, used for high-precision low-flow liquid measurement, held a 26.77% share of the intelligent flow meter market in 2026, according to Fortune Business Insights. Grand View Research also reports that the 2-inch and smaller pipe size segment is expected to see the fastest growth through 2030, driven by pharmaceutical and food & beverage demand — exactly the line sizes where low flow meters are specified.

Third, process complexity is rising. Coherent Market Insights projects the flow chemistry market, which depends on precision low flow metering, to reach USD 4.6 billion by 2032 at an 8.1% CAGR. P&S Intelligence values the global microfluidic devices market at USD 22.1 billion in 2024, growing at a 12.2% CAGR. More small-volume, higher-value processes mean more classified areas, more hygienic requirements, and more material compatibility questions.

One standards note is worth keeping in mind during evaluation. ISO 5167:2022 is the primary international standard for differential pressure flow measurement devices. It is often cited in small-pipeline specifications, but it governs differential pressure technology, not Coriolis or thermal measurement. Selecting a standard family that does not match the measuring principle is a common early-stage error.

The Certificate Set Behind Silver Automation Instruments Low Flow Meters

Silver Automation Instruments is a manufacturer of flow, pressure, level, and data logging instruments based in Nanjing, Jiangsu, China, founded in 2010, with a main export reach across Southeast Asia, South America, and Africa. The compliance documentation available for its low flow meter range consists of four certificates: one CE certificate, two ATEX certificates, and one ISO 9001 certificate. All four are relevant to a chemical, pharmaceutical, or petrochemical purchase, but they are not interchangeable.

ATEX documentation for explosive-atmosphere service — Zone 2 scope, referenced against IEC and EN 60079 series standards.

CE Marking: What Certificate 1N220422.SAIUW36 Actually Covers

The CE certificate registered under number 1N220422.SAIUW36 was issued by Ente Certificazione Macchine Srl with a scope of "Flow meter" and applies to the EU market. It references EN IEC 61326-1:2021, the electrical equipment standard for electromagnetic compatibility in measurement and control equipment. In practice, this document supports the CE marking argument for the flow meter family and is the certificate that European buyers usually ask for first.

It is important to read the scope precisely. A CE certificate of this type is issued against a defined product scope and a defined standard. If a project specifies additional directives or an EU type-examination route, the CE certificate is a starting point, not a substitute.

CE certification for the flow meter range, issued by Ente Certificazione Macchine Srl under EN IEC 61326-1:2021.

ATEX Zone 2: Two Certificates, Two Certification Vintages

The ATEX position is the part of the compliance picture that buyers most often get wrong, because two separate certificates exist with two different coverage lists.

Certificate ICR/VC/HM251296, issued by ICR on 2025-12-09 and valid until 2030-12-09, covers Zone 2 and references IEC 60079-0:2018+A11:2024, EN 60079-1:2014+A11:2024, and EN IEC 60079-31:2024. Its product list includes the Micro Coriolis mass flow meter SH-CMF-FE, the steam mass flow meter STLU-VFN, the low flow thermal mass flow meter SRK-DL, the thermal mass flow meter SRK-100, and the Coriolis mass flow meter SH-CM.

Certificate ECM 22 ATEX-B 0S05, issued by Ente Certificazione Macchine Srl on 2022-02-21 and valid until 2027-02-20, also covers Zone 2 and references EN IEC 60079-0:2018/AC:2020, EN 60079-1:2014, and EN 60079-31:2014. Its product list covers the thermal mass flow meter SRK-100 and the Coriolis mass flow meter SH-CM.

The practical difference matters at procurement stage. If a project requires the Micro Coriolis mass flow meter SH-CMF-FE, the 2025 ICR certificate is the document that names it. If a project requires the standard Coriolis mass flow meter SH-CM, two ATEX certificates name it, which gives the buyer a choice of which certification vintage to place in the technical file.

ATEX Zone 2 certificate ICR/VC/HM251296, issued by ICR, covering the SH-CMF-FE and SH-CM mass flow meters.

ISO 9001:2015: The Quality System Behind the Certificates

Certificate 79625Q0002107R0S, issued by ZHONGHONG CERTIFICATION (JIANGSU) CO.,Ltd on 2025-07-10 and valid until 2028-07-09, certifies a quality management system to ISO9001:2015. This document does not certify explosion protection or ingress protection. Its function is different: it gives procurement teams evidence that the manufacturing process — including the calibration tests performed as part of quality control — runs under a documented system.

For pharmaceutical and food-adjacent projects, this is often requested alongside the calibration record rather than instead of it.

ISO 9001:2015 certification covering the quality management system behind the low flow meter range.

Ingress Protection: IP65 on the SH-CM Coriolis Mass Flow Meter

Ingress protection is written into the product data, not into the ATEX certificate. The Coriolis mass flow meter SH-CM is documented with a protection level of IP65.

In the IP code, the first digit describes protection against solid objects and the second against water. A rating of IP65 therefore means the enclosure is dust-tight and protected against water projected by a nozzle from any direction. That rating supports washdown-adjacent and humid industrial environments, but it is not a submersion rating.

Buyers should treat the IP rating as a per-model attribute. Where a specific model datasheet does not state a rating, the correct action is to request confirmation from the supplier rather than assume the family rating applies.

Wetted Materials: Stainless Steel 304 and 316L Across the Range

Material selection is where compliance requirements and process chemistry meet. Across the Silver Automation Instruments low flow range, two grades are specified:

In general terms, 316L is the grade most often chosen where improved corrosion resistance matters, including many chloride-bearing and mixed chemical streams, while 304 is commonly specified for clean gas service where corrosion demand is lower. These are selection tendencies, not automatic rules. Corrosive duty may require a different wetted material entirely: for one chlorine gas application described later in this guide, a tantalum-wetted Coriolis mass flow meter was used.

Connection Types and Interface Verification

Process connection is a compliance item in its own right, because a certificate covers a product configuration, not an intention. In the low flow range documented here, the steam mass flow meter STLU-VFN is specified with process connections available as flanges, wafers, screws, or tri-clamp.

Tri-clamp and similar hygienic connections matter for pharmaceutical and biotech installations; flanged and wafer connections matter for chemical and petrochemical piping. When a project specifies a connection type that is not in the documented configuration list, that specification should be raised with the supplier at quotation stage rather than after the order.

Step-by-Step: How to Verify Low Flow Meter Compliance Before Ordering

The following workflow is written for the transition from Evaluation to Execution, when the measurement principle has already been chosen and the remaining task is to confirm that the selected meter can be accepted, installed, and audited.

1. Classify the installation point. Confirm the hazardous area classification from the plant's own documentation. The ATEX certificates referenced here cover Zone 2; if the installation point is not Zone 2, the certificate scope must be re-examined before anything else.
2. Match the model number to the certificate product list. Check the exact model — for example SH-CMF-FE or SH-CM — against the product list attached to the relevant ATEX certificate. Model families are not equivalent.
3. Read the referenced standards. Certificate ICR/VC/HM251296 references IEC 60079-0:2018+A11:2024, EN 60079-1:2014+A11:2024, and EN IEC 60079-31:2024; certificate ECM 22 ATEX-B 0S05 references EN IEC 60079-0:2018/AC:2020, EN 60079-1:2014, and EN 60079-31:2014. Compare these against the standards named in your own specification.
4. Check the validity window against the project timeline. In this certificate set, the CE certificate is valid until 2027-04-21, the ECM ATEX certificate until 2027-02-20, the ISO 9001 certificate until 2028-07-09, and the ICR ATEX certificate until 2030-12-09.
5. Verify ingress protection against the environment. IP65 is documented for the SH-CM Coriolis mass flow meter. Confirm that the model-specific rating suits the cleaning and humidity conditions at the installation point.
6. Verify wetted material against the fluid. 316L for SH-CMF-FE and SH-CM; 304 for the SRK-100 thermal mass flow meter; 304 or 316 for the STLU-VFN steam mass flow meter. Where the process fluid is aggressive, discuss alternative wetted materials such as the tantalum option used in the chlorine gas case below.
7. Confirm the process connection configuration. Documented options for the steam mass flow meter include flanges, wafers, screws, or tri-clamp. Confirm the connection against the plant piping standard and the hygienic requirement of the process.
8. Fix the commercial and acceptance terms. Silver Automation Instruments quotes a minimum order quantity of 1 unit, delivery terms of EXW, FOB, or CIF, and payment terms of 100% T/T in advance. Acceptance criteria are a pre-shipment calibration test, visual inspection, and an optional factory acceptance test (FAT). The stated lead time is 10–12 working days, with a monthly production capacity of 2000 units.

Pre-shipment calibration testing is part of the documented quality control process for low flow meters.

Use Cases: Where Certification, Material, and Low Flow Accuracy Interlock

The following field cases show how compliance and process requirements combine in the applications most relevant to chemical, pharmaceutical, and petrochemical buyers.

Corrosive Chlorine Gas — Malaysia

A petrochemical site in Malaysia uses one Coriolis mass flow meter to measure corrosive chlorine gas flow. The meter uses tantalum wetted material to handle the corrosion load, and the installation has delivered high-precision chlorine gas flow measurement. This case illustrates the point made earlier: when the fluid is aggressive, the wetted material specification is the controlling compliance variable, and it must be raised at enquiry stage.

High-Pressure Nitrogen at 700 bar — Chile

In Chile, a single Coriolis mass flow meter measures nitrogen gas at approximately 700 bar. The sensor uses a high-pressure design capable of withstanding 700 bar or higher, and the project has achieved stable measurement for more than three years. For compliance documentation, high-pressure duty means the pressure boundary specification sits alongside the ATEX and material documentation in the technical file.

High-pressure mass flow meter configuration deployed for nitrogen gas measurement at around 700 bar.

Cryogenic Liquid Oxygen at −183 °C — India

In India, three Coriolis mass flow meters measure liquid oxygen at −183 °C (90 K). Customer feedback reported measurement accuracy within 0.2% to 0.5%. Ultra-low temperature service is a documented application boundary for the Coriolis range, which is specified for fluid temperatures from −200 °C to 350 °C.

Low Flow Air Leak Detection at 2 sccm — China

Three units of the low flow thermal mass flow meter SRK-DL are used in China to detect air leakage as low as 2 sccm (2 ml/min). The installation has been running for more than ten years. The SRK-DL is specified for a flow range of 2 sccm to 30 SL/M with ±1% F.S accuracy, and is used in semiconductor, medical, analytical instrument, fuel cell, and environmental monitoring applications.

High Viscosity Syrup — Thailand

A pharmaceutical and food-adjacent producer in Thailand uses a Coriolis mass flow meter for high viscosity syrup, achieving accuracy up to 0.1%. The meter also displays volume flow rate, sugar concentration, and density, and has been in operation for more than five years. Where multiple process variables are displayed, calibration documentation becomes part of the quality record, not just the purchase file.

Low-Pressure Biogas — Singapore

Four insertion-type SRK-100 thermal mass flow meters, with PTFE-coated sensors, measure biogas in a 4-inch pipeline at around 10 mbar. The project has been operating for more than five years. PTFE coating is an example of a material-level adaptation for slightly corrosive gas — a change that must be reflected in the order specification and the technical documentation.

Compliance-Relevant Comparison of Low Flow Meter Models

Three observations follow from this table. First, ATEX coverage is not identical across the range: the Micro Coriolis mass flow meter SH-CMF-FE, the low flow thermal mass flow meter SRK-DL, and the steam mass flow meter STLU-VFN are named on the 2025 ICR certificate, while the SH-CM and SRK-100 are named on both ATEX certificates. Second, IP65 is documented for the SH-CM specifically, so per-model confirmation is the correct approach for the remaining models. Third, material grade changes with the product type, which is why the wetted material should always be verified against the fluid before the purchase order.

Frequently Asked Questions

Does the SH-CMF-FE micro Coriolis mass flow meter carry ATEX approval, and which zone does it cover?

Yes. The Micro Coriolis mass flow meter SH-CMF-FE is listed on ATEX certificate ICR/VC/HM251296, issued by ICR with a scope of Zone 2, referencing IEC 60079-0:2018+A11:2024, EN 60079-1:2014+A11:2024, and EN IEC 60079-31:2024. The certificate was issued on 2025-12-09 and is valid until 2030-12-09. The same model also appears on CE certificate 1N220422.SAIUW36, which references EN IEC 61326-1:2021, and on ISO9001:2015 certificate 79625Q0002107R0S. Zone 2 applies where an explosive atmosphere is not expected in normal operation and exists only briefly if it occurs; installations classified as Zone 0 or Zone 1 fall outside this certificate scope.

What ingress protection and wetted material should I expect from these low flow meters?

IP65 is documented for the Coriolis mass flow meter SH-CM, meaning a dust-tight enclosure protected against water jets. Wetted material is specified as stainless steel 316L for the Micro Coriolis mass flow meter SH-CMF-FE and for the SH-CM, stainless steel 304 for the SRK-100 thermal mass flow meter, stainless steel for the SRK-DL low flow thermal mass flow meter, and stainless steel 304 or 316 for the STLU-VFN steam mass flow meter. Where the model datasheet does not state an IP rating, confirm it with the supplier against your cleaning and humidity conditions. For aggressive fluids, alternative wetted materials may be required — a chlorine gas application in Malaysia used a tantalum-wetted Coriolis meter.

Can Silver Automation Instruments supply OEM low flow meters for microfluidic systems?

Yes. Silver Automation Instruments provides both OEM and ODM production services, so a microfluidic system builder can either have meters manufactured to an existing design for its own brand, or work with the manufacturer's design and production capability to develop a new product. Logo customization is offered, monthly production capacity is 2000 units, and the minimum order quantity is 1 unit. For microfluidic duty, the relevant low flow range covers the Micro Coriolis mass flow meter SH-CMF-FE at 40 g/h to 1000 kg/h with accuracy of ±0.25% to ±0.5%, and the low flow thermal mass flow meter SRK-DL at 2 sccm to 30 SL/M with ±1% F.S accuracy.

What are the minimum order quantity, payment, and delivery terms?

The minimum order quantity is 1 unit. Delivery terms are EXW, FOB, or CIF, and payment terms are 100% T/T in advance. Acceptance criteria are a pre-shipment calibration test, visual inspection, and an optional factory acceptance test (FAT). These terms apply across the low flow meter range, including the SH-CMF-FE and SH-CM models discussed in this guide.

Can I validate the meter before shipment, and how long does delivery take?

Yes. Calibration tests are performed as part of the documented quality control process, so a pre-shipment calibration test and visual inspection form the standard acceptance route, with factory acceptance testing available as an option for projects that require it. The stated lead time is 10–12 working days, and after-sales support is provided remotely. To start a compliance review for a specific project, share the zone classification, fluid, and line size with the supplier so the correct certificate, wetted material, and connection configuration can be confirmed in writing — contact sales@silverinstruments.com or via WhatsApp at +86 18936759191. The full product catalogue is available in the Silver Automation Instruments brochure.

Conclusion

Compliance for a low flow meter is a matching exercise, not a paperwork exercise. The certificate must name the model, the zone scope must match the hazardous area study, the IP rating must match the environment, the wetted material must match the fluid, and the connection configuration must match the piping standard. When all five items align, ATEX approval, IP65 ingress protection, CE marking, and an ISO 9001 quality system become what they are meant to be: a documented basis for accepting a meter into a chemical, pharmaceutical, or petrochemical process.

For the range described in this guide, the verifiable position is specific: ATEX Zone 2 coverage under certificates ICR/VC/HM251296 and ECM 22 ATEX-B 0S05, CE certification under 1N220422.SAIUW36 referencing EN IEC 61326-1:2021, ISO 9001:2015 certification under 79625Q0002107R0S, stainless steel 316L on the SH-CMF-FE and SH-CM, and documented connection options including flanges, wafers, screws, and tri-clamp. Reviewing these against a project's own requirements before the order is placed is the step that prevents most compliance rework.

Packing and export preparation — standard orders ship within the stated 10–12 working day lead time.