| 1 | Product and material specification | Confirm the base material, tube dimensions, wall thickness, connection design, and whether the arm is hollow or solid. Check that the specification matches the intended water system and installation. | Approved product drawing and purchase specification; material grade should be stated rather than described only as “stainless” or “brass.” | Dimensioned drawing, material declaration, and a signed specification sheet for the quoted model. |
| 2 | Thread compatibility | Specify the thread standard and size at each connection. G 1/2 (BSPP) and 1/2-14 NPT are different thread forms and are not automatically interchangeable. | ISO 228-1 covers pipe threads where pressure-tight joints are not made on the threads; ASME B1.20.1 covers inch pipe threads, including NPT. | Thread callout on the drawing, thread gauge or inspection record, and a sample tested with the intended mating fitting. |
| 3 | Pressure and leakage performance | Check whether the complete shower arm assembly is tested for leakage and pressure under conditions appropriate to the destination market and the product design. | ASME A112.18.1/CSA B125.1 is a plumbing supply fittings standard used in North American markets; applicability depends on product scope and local requirements. | Test procedure, test conditions, dated results, and reports that identify the exact product or model tested. |
| 4 | Corrosion resistance and finish | Identify the finish type, coating layers, and intended environment. Finish appearance alone does not establish corrosion resistance or coating durability. | ASTM B456 specifies requirements for electrodeposited coatings of copper plus nickel and nickel plus chromium on specified substrates. | Finish specification, coating-thickness records where relevant, and test reports for the specified finish and substrate. |
| 5 | Drinking-water contact requirements | Determine whether wetted materials are subject to drinking-water contact rules in the destination market. Requirements depend on market, product scope, and materials. | NSF/ANSI/CAN 61 addresses health effects of drinking-water system components; it is not a universal requirement for every shower arm or market. | Applicable certification listing or test documentation that covers the relevant product, materials, and intended market. |
| 6 | Quality management | Review how the supplier controls incoming materials, production, inspection, nonconforming products, and corrective actions. | ISO 9001 specifies quality management system requirements. Certification indicates a certified management system scope, not automatic certification of every product. | Current certificate, issuing body details, scope, site address, and sample inspection or corrective-action records. |
| 7 | Customization capability | Agree on adjustable dimensions, bend angle, projection, connection type, finish, logo placement, and packaging before production. Confirm any tooling or sampling charges. | Custom dimensions and finishes are product-specific; there is no single standard that guarantees a supplier can provide every requested option. | Approved drawings, signed finish samples, tooling terms, sample approval record, and written change-control process. |
| 8 | Inspection and traceability | Define acceptance criteria for dimensions, threads, finish, leakage, packaging, and sampling. Clarify how production lots and test records are identified. | ISO 2859-1 provides sampling plans indexed by acceptance quality limit (AQL) for lot-by-lot inspection; the buyer and supplier must agree on its application. | Inspection plan, lot identification method, inspection reports, and agreed sampling level and acceptance criteria. |
| 9 | Export documentation | Confirm the exporter can prepare documents required by the transaction and destination, and that product descriptions and quantities match across documents. | Common shipping documents include a commercial invoice, packing list, and transport document. Exact customs and import requirements vary by destination. | Sample redacted export documents, packaging details, country-of-origin information, and confirmation of the agreed Incoterm. |
| 10 | Packaging and shipment readiness | Check protection against scratching, denting, moisture, and movement in transit. Validate carton dimensions, labeling, packing quantity, and pallet requirements. | Packaging and marking requirements depend on the buyer, carrier, destination, and applicable transport rules; wood packaging may be subject to ISPM 15 requirements. | Packaging specification, carton test or transit-test records where required, product labels, and pre-shipment packing photos. |
