Introduction
- Isolated use. MS81-2021 rarely stands alone. You must cross-reference it with electrical, fire, and building codes.
- Ignoring the annexes. Informative annexes (e.g., Annex A – Rationale for Changes) are often considered part of the standard’s intent, even if not normative.
- Misinterpreting “shall” vs. “should”. In standards language, “shall” is mandatory; “should” is recommended. Many facilities treat “should” as optional and later fail audits.
- Using a printed version. Safety standards get amendments (corrections) frequently. If you printed the PDF on January 15, 2022, but an erratum was released on June 1, 2022, your printed copy is already outdated. Always reference the live PDF.
Design & Materials: The standard outlines strict material specifications (such as ductile iron or cast iron) to prevent corrosion and ensure structural integrity under high pressure.
: Drawings created after the enforcement of the latest standards follow a new classification system (classes f, m, or c). Old Drawings
Weaknesses / limitations
- Ambiguity in edge cases: Some clauses use imprecise wording (e.g., “acceptable level,” “reasonable effort”) that can cause differing interpretations.
- Regional specificity: If intended for one jurisdiction, certain regulatory references or measurement units may not map cleanly to other regions.
- Updates & versioning: If adopted late, users may still rely on superseded practices; the standard may lack a clear migration path from prior versions.
- Cost/complexity: Some test or documentation requirements add project overhead that smaller firms might find burdensome without clear cost–benefit justification.