The OSBR Handbook

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Data Protection ​

This is the standard the Quality Gate's Security lens holds work to whenever a system handles personal data — the data a user entrusts to us. It sits alongside the Security Policy (which keeps that data safe from attackers) and describes the other half of the duty: the user's own rights over their data — to know what they agreed to, to see it, to take it, to leave with it — and the discipline that makes those rights answerable years later rather than promised in prose. It builds on the Infrastructure Planning Policy (data residency, backups, durability) and the Database Guidelines (schema and history design).

This is an engineering standard: how we design schemas, record consent, keep history, and send mail so that personal data is handled correctly by construction. The user-facing Privacy Policy — the legal notice of what we collect and why — is the organisation-level Privacy Policy standard; this page is what the system must actually do so that policy is truthful. As everywhere in the handbook, deviations are allowed but must be deliberate and justified in the project's design notes.

Data protection is where OSBR's values become load-bearing. Be Nice: the user always knows what they agreed to and what we hold, and can retrieve both — and anyone who comes after us, human or AI, can see how a record reached its current state without having to guess. Be Kind: the user owns their data; we only ever hold it on loan, so leaving must be as easy as joining, we never sneak a material change past someone by burying it in "continued use," and we never quietly erase a fact someone may later depend on. Be Strong: we build the audit trail before we need it, so that under scrutiny — a regulator, a dispute, a breach, a corrupted write — the truth is already recorded, tamper-evident, and reconstructable. Humans and AI agents design and review these systems here as collaborators, held to one bar.

Silence is not consent, and the past is a fact, not a field. If we cannot show a clear affirmative act against a specific version, we do not have consent. If we overwrite state in place, we are choosing — usually without deciding to — that history is worthless. It rarely is.

How to read this policy ​

  • Requirement levels follow RFC 2119, as in the Coding Style Guide. MUST / MUST NOT are absolute. SHOULD / SHOULD NOT state a strong default overridable only with a documented reason. MAY marks a free choice.
  • Named practice. Where a rule adopts an external standard or legal regime, it is named inline and cited under References. OSBR's home regime is Malaysia's PDPA (Personal Data Protection Act 2010, as amended in 2024); its Japanese parent studio and international clients also bring Japan's APPI, the EU's GDPR, and CCPA/CPRA into scope, and these rest on the same core duties. We adopt the criteria — PDPA, APPI, GDPR, CCPA/CPRA, SQL:2011, the email authentication RFCs — and right-size them for an SME; we do not adopt the headcount behind a large organisation's compliance function. The organisation-level notice these controls make truthful is the Privacy Policy.

1. Goal ​

The goal of data protection at OSBR is that personal data is handled correctly by design, and every promise we make about it is one the system can actually keep. Concretely, for any personal data we hold, we can:

  • Prove consent — reconstruct, for that exact user against that exact wording at that exact moment, what they affirmatively agreed to.
  • Honour the user's rights — let them see all their data, take a portable copy, and delete their account and data completely, as first-class product features and not back-office favours.
  • Reconstruct the past — answer "what did this record look like then?" because state transitions were recorded as history, not overwritten into silence.
  • Hold only what we should — collect the minimum, retain it for a documented period, and keep it where it is legally allowed to live.
  • Reach the inbox with restraint — send only mail a recipient expected and can act on, without damaging the reputation every other message depends on.

These capabilities are almost impossible to retrofit. They MUST be designed into the very first user-data model, because a schema that never planned for deletion, history, or consent versioning cannot grow them later — the history you need has already been overwritten by the time you need it.

2. Responsibility ​

  • Whoever designs the first user-data schema owns the shape of protection. Define deletion semantics and cascade behaviour, the retention period and category of each field, and the history structure for every stateful record — all at schema time, before the first migration ships. "Add history/deletion later" is a design defect, not a backlog item.
  • Every developer touching user data owns minimization. Collect only what the feature uses; do not add a column, log line, or third-party sync that widens what we hold without a reason recorded in the design notes. Write state transitions as appends, never as destructive updates.
  • The PR author who introduces an email trigger owns justifying it, classifying it, and confirming authentication and (where required) unsubscribe controls are in place before it can send in production.
  • The reviewer treats data-protection surface as reviewable: an unexplained send_email(...), a schema with no answer for "where does the old value go?", or a consent record with no version is a change that needs an owner and a reason — refused the same way code without a security review is refused.
  • Legal owns the wording of each ToS / Privacy Policy version, classifies every change as material or non-material with a recorded rationale, and sets the retention floor for records the law requires us to keep.
  • The project's technical owner ensures export, deletion, retention, and history are on the roadmap from v1, and audits actual retention against the published privacy policy at least quarterly.
  • AI agents are first-class contributors here and held to exactly the same bar; the human who merges an agent's schema, migration, or consent flow owns it.

Privacy is everyone's job, not a compliance team's — this is Cavoukian's principle of protection embedded into design rather than bolted on afterwards.

3. Practices ​

3-1. Design data protection into the first schema ​

Export, deletion, retention, minimization, consent versioning, and change history MUST be decided when the first user-data model is designed, not deferred. For every table holding personal data, the design notes MUST answer, before the first migration ships: what category each field is, its retention period, what happens to it on account deletion (hard delete, anonymise, or retain under a lawful exception), and where else the data flows. A schema with no answer for "what happens to this row when the user leaves?" is not finished.

3-2. If a record holds state, history is a requirement — not an enhancement ​

For any record that carries status, state, a mutable classification, a price, a policy version, or any field whose previous value could later be asked about, a change-history structure MUST be designed in from the start.

  • The design MUST make it possible to answer, for any record: what its state was at an arbitrary past instant, and what sequence of changes produced the current state.
  • Each recorded change SHOULD capture at minimum the entity identifier, the new state (or delta), a valid-from timestamp, the actor / cause, and — where the history feeds audit — enough context to explain why it changed.
  • "We'll add history when we need it" MUST be treated as a design defect: by the time you need it, the history you need has already been overwritten. If history is genuinely not required for a record, that decision MUST be recorded in a schema comment or design note, so it is a choice and not an omission.

3-3. Choose a history structure that fits the record ​

There is more than one well-established way to keep history. Engineering MUST choose deliberately from these (or a documented equivalent) rather than default to overwrite because it is less code today. All are appropriate; the wrong choice is none.

StructureKeepsBest whenAnchor
Append-only / immutable audit logOne immutable row per change (who/what/when), separate from the live rowYou need a tamper-evident trail alongside a normal mutable tableWORM / audit-log discipline
System-versioned temporal tableEvery row version with [valid-from, valid-to] system time, queryable "AS OF" a past instantThe database can own history transparently and you want point-in-time SQLSQL:2011 system-versioned tables
Bi-temporalTwo timelines — valid time (when the fact was true) and transaction time (when we recorded it)The real-world effective date differs from when we learned it (back-dated corrections, retroactive consent)SQL:2011 bi-temporal
Slowly Changing Dimension (Type 2)A new row per change with effective/expiry dates and a "current" flagAnalytical / warehouse dimensions reporting over historical attribute valuesKimball SCD Type 2
Event SourcingThe full sequence of state-changing events; current state is a derived projectionState is inherently a sequence of business events and the event log is the source of truthFowler / Greg Young Event Sourcing

Whichever is chosen, the previous value MUST remain retrievable after a change. A change that leaves no recoverable prior state is an overwrite, whatever it is called. Corrections SHOULD be new records that supersede, not edits that erase.

3-4. Derive "current", don't destroy "past" ​

The current state of a stateful record MUST be derivable from its history, not maintained by destroying the history.

  • "Current" is a projection / replay over the events, or the row with the latest valid-from (or is_current = true) — computed, not carved out by deletion.
  • A denormalised current-state column or table is permitted as an optimisation, but it MUST be reproducible from the history and MUST NOT be the only place the fact lives.
  • Withdrawals, reversals, and cancellations MUST be recorded as new entries (a cancelled event, a superseding row), never as deletion of the prior entry. That something was active and then cancelled is itself history worth keeping.

3-5. Make history queryable, not just retained ​

Retained history no one can query is a liability, not an asset — it costs storage and answers nothing.

  • Each history structure MUST carry the temporal join keys needed to reconstruct a point in time: a stable entity id plus the time bounds (valid-from/valid-to, effective/expiry dates, or event sequence + timestamp).
  • Point-in-time reconstruction ("state AS OF date D") SHOULD be a documented, tested query — not a one-off archaeology exercise when a dispute lands.
  • Where the database offers it natively (SQL:2011 FOR SYSTEM_TIME AS OF, or engine equivalents), prefer the native mechanism over hand-rolled history tables: less code, and harder to get subtly wrong.

3-6. Data minimization ​

The least data we can hold is the safest data — data we never collected can never leak, never needs exporting, and never needs deleting.

  • Collect only fields the feature actually uses (PDPA General Principle; the APPI's purpose-of-use limitation; GDPR Art. 5(1)(c)). Do not collect "just in case."
  • Prefer not storing personal data at all where a design allows it — derive rather than store, reference rather than copy.
  • Logs, analytics, and error reports are personal data when they carry user identifiers: minimize and set retention on them too, consistent with the Security Policy's treatment of logs as protected assets.

3-7. Documented retention, audited against the running system ​

Retention MUST be a decision on the record, not an accident of "we never delete anything" (PDPA Retention Principle; the APPI's retention limits; GDPR Art. 5(1)(e), storage limitation).

  • Each category of personal data MUST have a documented retention period and a reason. "Indefinite" is a choice that must be justified, not a default.
  • Retention SHOULD be enforced automatically — a scheduled job that deletes or anonymises data past its period — not left to manual cleanup that never happens.
  • Retention periods MUST be reflected truthfully in the user-facing privacy policy and audited against the running system at least quarterly. If the database keeps data longer than the policy promises, one of the two is wrong — fix it.
  • History (§3-2) is bounded by two independent floors: keep at least as long as law and audit require (consent, financial, personal-data-change records), and keep no longer than minimization allows for personal data. Neither "keep everything forever" nor "overwrite immediately" is automatically correct; design the window to satisfy both.

3-8. Self-service data export (portability) ​

A user MUST be able to export their own data themselves, without emailing support and without a developer running a query (PDPA Access Principle and the data-portability right added by the 2024 Amendment; the APPI's 開示 access right; GDPR Art. 20).

  • Export MUST be portable and machine-readable — JSON or CSV, documented schema, UTF-8 — per the Art. 20 standard of "structured, commonly used and machine-readable."
  • Export SHOULD cover all data tied to the user — content they created, settings, retained activity — matching the access right of GDPR Art. 15, not just their profile.
  • Export SHOULD be self-service in the product UI. Large exports MAY be generated asynchronously and delivered via a time-limited, authenticated link.
  • The export path MUST authenticate the requester as the data subject — an unauthenticated export endpoint is a data-exfiltration endpoint. A portable export is the difference between a user choosing to stay and a user trapped into staying; make the door visible.

3-9. Complete account and data deletion (erasure) ​

A user MUST be able to delete their account and have their personal data actually deleted (PDPA Access Principle and the right to withdraw consent; the APPI's 利用停止・消去 cease-use/erasure right; GDPR Art. 17; CCPA/CPRA right to delete).

  • Deletion semantics and cascade MUST be defined at schema time (§3-1): for every table, decide up front whether the row is hard-deleted, anonymised, or retained under a lawful exception, and wire the foreign-key cascade / cleanup job to match.
  • Deletion MUST propagate to all copies: primary store, caches, search indexes, analytics, and any third-party processor the data was shared with. Enumerate these at design time — a copy you forgot about is a copy you did not delete.
  • Backups are the documented exception: personal data MAY persist in encrypted backups until they age out on normal rotation, provided the window is documented and the data is not restored into live use.
  • Where full erasure is impossible because a lawful obligation requires a record (e.g. financial/transaction records), anonymise rather than retain identifiable data, and record which exception applies.
  • Deletion SHOULD be self-service, with a clear confirmation and a stated completion timeframe. A short, cancellable, disclosed grace period (to guard against account takeover or misclicks) is acceptable.

3-10. Data subject request (DSR) workflow ​

Even with self-service, some access/deletion/portability requests arrive by other channels. Have a defined path for them.

  • There MUST be a known, documented way to receive and fulfil an access, deletion, or portability request, with a named owner.
  • Requests SHOULD be fulfilled within the statutory window (GDPR: one month; CCPA/CPRA: 45 days), and the requester's identity MUST be verified before data is handed over or destroyed.
  • Wherever possible the DSR workflow SHOULD reuse the same export and deletion machinery as the self-service features — one code path, not a fragile manual side channel.

3-11. Data residency and sovereignty ​

"Data sovereignty" also means honouring where the data is legally allowed to live — the PDPA's cross-border transfer rule (under the 2024 Amendment, transfer only to a place with substantially similar or an adequate level of protection, or on another permitted ground such as consent), the APPI's cross-border-provision rule, and the GDPR's Chapter V transfer safeguards.

  • Know and document which region personal data is stored and processed in, and keep it consistent with client and legal requirements — this extends the residency note in the Infrastructure Planning Policy.
  • When a client or jurisdiction requires data to stay in a region, that constraint MUST be reflected in the infrastructure, not just promised in prose.

3-12. Version every legal document with a persistent identifier ​

Each ToS and Privacy Policy MUST carry a persistent, immutable version identifier. A published version is frozen — never edited in place; a change produces a new version.

  • Each version MUST record a stable version id (e.g. privacy-policy@2026-07-15 or a monotonic v7), its effective date, the full text (or a content hash), and the classification of the change relative to the previous version (§3-14).
  • Superseded versions MUST remain retrievable forever: a user who consented to v5 MUST be able to retrieve the exact v5 text they saw.
  • The identifier MUST be the join key between the consent event (§3-13) and the document text. A consent record pointing at "the Privacy Policy" with no version is not a valid record — the PDPA Notice and Choice Principle and GDPR Art. 7(1) put the burden on us to demonstrate consent, which is impossible for wording we can no longer reproduce.

3-13. Record each consent as an immutable event ​

Every act of consent MUST be written to an append-only, immutable audit trail as a discrete event — a specific application of the history discipline in §3-2 to §3-5. The event is a fact about the past; it is never updated or deleted.

Each consent event MUST capture at minimum:

  • User — a stable subject identifier.
  • Policy type — e.g. terms-of-service, privacy-policy, cookie-consent, or a specific processing purpose.
  • Policy version — the persistent identifier from §3-12 (which exact wording was shown and agreed to).
  • Timestamp — a trusted, timezone-explicit UTC timestamp of the affirmative act.
  • Consent action — granted or withdrawn (withdrawal is a new event, never a deletion of the grant).
  • Method / context — how consent was captured (checkbox on signup, re-consent modal) and, where practical, the collection point, so the record shows a clear affirmative action.

Rules:

  • Events MUST be immutable; corrections are appended, never rewritten. The store SHOULD be append-only / WORM-style (hash-chained or write-once) so tampering is detectable. The current consent state of a user is derived by replaying their event stream (§3-4), not stored as an overwritable flag.
  • Withdrawal MUST be as easy as granting (PDPA right to withdraw consent; GDPR Art. 7(3)) and MUST itself be recorded as an event.
  • The consent request MUST be clearly distinguishable from other matters — not buried inside unrelated ToS acceptance (GDPR Art. 7(2)). This is how Consent Management Platforms operate under the IAB TCF: consent encoded per-purpose and per-vendor against a versioned specification, not a single opaque yes.

3-14. Classify changes: material vs non-material ​

Every new version MUST be classified by Legal before publication, with the rationale recorded alongside the version.

  • Non-material change — wording clarifications, typo fixes, restructuring, contact-detail updates: anything that does not alter what data is collected, the purposes, legal basis, recipients, retention, user rights, or cross-border transfers. Non-material changes MUST be notified to users but do not require fresh consent.
  • Material change — any change to the scope or substance of processing: new categories of personal data, new purposes, new recipients or sharing, new international transfers, changed retention, changed legal basis, or any expansion of what the user is agreeing to. A material change invalidates prior consent for the changed scope and MUST trigger re-consent (§3-15).

When in doubt, classify as material. The cost of over-classifying is one extra prompt; the cost of under-classifying is processing personal data without a valid legal basis. Be Kind — err toward asking again.

3-15. Force re-consent on material changes — never rely on "continued use" ​

On a material change, OSBR MUST obtain fresh, affirmative consent against the new version before continuing to process personal data under the new scope.

  • OSBR MUST block or limit access to force re-consent — e.g. an interstitial the user must actively act on. Access to the changed processing is gated until a new consent event (§3-13) is recorded against the new version.
  • OSBR MUST NOT treat continued use, silence, inactivity, or a pre-ticked box as acceptance. Consent requires a clear affirmative act (GDPR Recital 32; Art. 4(11) — freely given, specific, informed, unambiguous). This is the same principle the ePrivacy Directive applies to cookies: prior, informed, affirmative consent, not opt-out-by-continuing.
  • The re-consent flow MUST show, or clearly link to, what changed, so consent is informed.
  • Gating SHOULD be proportionate: limit access to the affected feature or processing, not the user's own data or account. A user who declines MUST retain the ability to access and export their existing data (§3-8) and to withdraw.
  • For non-material changes, notice is sufficient and MUST still be logged.

3-16. Notice at collection ​

At the point personal data is first collected, OSBR MUST present a notice at collection identifying the categories of data and the purposes, and link to the current Privacy Policy version (the PDPA Notice and Choice Principle; the APPI's purpose-of-use notice; CCPA/CPRA notice-at-collection; the informed limb of GDPR consent). The version shown at collection MUST match the version recorded in the consent event.

3-17. Justify and review every email trigger ​

An email trigger is any code path that sends a message to a person. Each new or changed trigger MUST be described in the PR that introduces it: what event fires it, who receives it, why it needs to exist, and how often it can fire per recipient. A trigger that cannot be justified in a sentence should not ship — reviewers treat an unexplained send_email(...) the way they treat an unexplained network call.

3-18. Classify transactional vs marketing ​

Every trigger MUST be classified as transactional or marketing / notification, because the classification determines the legal and consent rules that apply.

  • Transactional — a message sent in direct response to an action or relationship the recipient initiated: password resets, receipts, security alerts, booking confirmations, account notices. These generally do not require prior opt-in but MUST still identify the sender honestly and carry no marketing content, or they lose transactional status.
  • Marketing / notification — anything promoting a product, feature, re-engagement, digest, or optional update. These require consent and unsubscribe controls (§3-20, §3-21).

The primary purpose of a message, not its label, decides classification (the CAN-SPAM "primary purpose" test): a "receipt" padded with promotions is a marketing message. When a message mixes purposes, the stricter rule wins.

3-19. Authenticate the domain before the first production send ​

The sending domain MUST have SPF, DKIM, and DMARC configured and verified before any production email is sent from it — not after deliverability problems appear. Unauthenticated mail is filtered, spoofable, and increasingly rejected.

  • SPF — publish the sending service's hosts in a DNS TXT record so receivers can verify the envelope sender is authorised.
  • DKIM — sign outgoing mail with a domain key so receivers can verify it was not altered and genuinely came from the domain.
  • DMARC — publish a policy telling receivers what to do when SPF/DKIM fail and where to send aggregate reports. Start at p=none to observe, then move to p=quarantine / p=reject once aligned.
  • BIMI (SHOULD, once DMARC is enforced) — publish a verified brand logo; requires an enforced DMARC policy and, for most providers, a Verified Mark Certificate.

Bulk senders MUST additionally meet the Google & Yahoo 2024 bulk-sender requirements: authenticate with SPF and DKIM, publish a DMARC policy, keep reported spam rates below the 0.3% threshold, send from aligned domains, and provide one-click unsubscribe (RFC 8058) honoured within two days.

3-20. Send through a managed service ​

Production email MUST go through a managed email service provider (ESP) — never a self-operated SMTP server or a raw library talking directly to recipient MX hosts. Managed providers give us authenticated sending, reputation monitoring, and bounce/complaint handling a hand-rolled sender does not. Bounces and complaints MUST feed a suppression list so we stop mailing addresses that hard-bounce or complain; ignoring them is the fastest way to lose sender reputation and get all our mail — including transactional — filtered.

3-21. Unsubscribe and preference management before any marketing send ​

No marketing or notification email may be sent in production until unsubscribe and preference management are in place. Every such message MUST include a clear, working unsubscribe mechanism that takes effect promptly and requires no login or reply. This is both an OSBR courtesy and a hard legal requirement in every market we operate in:

  • CAN-SPAM (US) — a visible, working opt-out honoured within 10 business days, honest headers and subject lines, and a physical postal address.
  • 特定電子メール法 (Japan) — an opt-in regime: advertising email may be sent only to recipients who consented in advance, with consent records kept, sender identification present, and an opt-out path in every message.
  • GDPR (EU/EEA) — marketing to individuals requires a freely given, specific, informed, unambiguous opt-in, records proving it, and withdrawal as easy as it was given (§3-13).

Where these regimes overlap for a recipient, apply the strictest: default to opt-in, keep consent records, and make opting out trivial.

3-22. Protect deliverability and sender reputation as a shared asset ​

Sender reputation is domain-wide: a noisy marketing trigger degrades delivery of password resets and receipts too. Send only wanted mail, keep volume and cadence steady rather than spiky, warm up new sending domains/IPs, monitor bounce and complaint rates against provider thresholds, and remove addresses that bounce or complain. Reputation is earned slowly and lost in a single bad send.

4. Design-time checklist ​

Before the first user-data migration ships, the design notes SHOULD answer:

  • [ ] What personal data does this model hold, and what category is each field?
  • [ ] What is the retention period for each, and why? Does the privacy policy's stated retention match what the schema actually does?
  • [ ] On account deletion, what happens to each table — hard delete, anonymise, or retain under which exception? Is the cascade wired?
  • [ ] Where else does this data flow (cache, index, analytics, third parties), and how is each cleaned on deletion?
  • [ ] How does a user export this data themselves, in a machine-readable format?
  • [ ] For every field that holds state / status / a mutable classification: is a history structure identified (§3-3), or is "no history required" recorded as a deliberate decision?
  • [ ] Is the previous value retrievable after any change, "current" derivable from history, and are withdrawals/cancellations recorded as new entries?
  • [ ] Does the history carry the temporal keys to answer "state AS OF a past instant," and does retention satisfy both the legal floor and the minimisation ceiling?
  • [ ] For consent: is every record joined to a persistent policy version, written append-only, and captured as a clear affirmative act?

If personal-data state can be overwritten with no recoverable prior value, or consent cannot be tied to an exact version, the design is not ready.

References ​

Privacy law. The organisation-level notice these controls uphold is the Privacy Policy.

Malaysia

  • Personal Data Protection Act 2010 (Act 709) and the seven Personal Data Protection Principles — General, Notice and Choice, Disclosure, Security, Retention, Data Integrity, Access — Personal Data Protection Commissioner / JPDP — https://www.pdp.gov.my/
  • Personal Data Protection (Amendment) Act 2024 (Act A1727) — mandatory breach notification, Data Protection Officer duty, data portability, cross-border transfer to jurisdictions with substantially similar / adequate protection, and "data user" → "data controller" — https://www.pdp.gov.my/

Japan

  • 個人情報保護法 (Act on the Protection of Personal Information, APPI) — Personal Information Protection Commission (PPC) — purpose-of-use specification, cross-border-provision rule, and 開示・訂正・利用停止 rights — https://www.ppc.go.jp/en/legal/
  • 特定電子メール法 — 特定電子メールの送信の適正化等に関する法律 (Japan) — opt-in regime for advertising email.

EU / US / international

Privacy engineering frameworks

History & temporal patterns

  • Martin Fowler — Event Sourcing — https://martinfowler.com/eaaDev/EventSourcing.html
  • Greg Young — Event Sourcing / CQRS — the event log as authoritative source of truth, read models derived from it.
  • Martin Fowler — Temporal Patterns (Audit Log, Effectivity, bi-temporal model) — https://martinfowler.com/eaaDev/timeNarrative.html
  • SQL:2011 (ISO/IEC 9075:2011) — system-versioned temporal tables & bi-temporal data; FOR SYSTEM_TIME AS OF point-in-time queries.
  • Ralph Kimball — Slowly Changing Dimensions, Type 2 (The Data Warehouse Toolkit).
  • Append-only / immutable audit log (WORM) — write-once, tamper-evident change records kept alongside the live table.

Email authentication & deliverability

  • SPF — RFC 7208, Sender Policy Framework (SPF) for Authorizing Use of Domains in Email, Version 1.
  • DKIM — RFC 6376, DomainKeys Identified Mail (DKIM) Signatures.
  • DMARC — RFC 7489, Domain-based Message Authentication, Reporting, and Conformance.
  • One-click unsubscribe — RFC 8058, Signaling One-Click Functionality for List Email Headers.
  • BIMI — Brand Indicators for Message Identification (AuthIndicators Working Group; requires enforced DMARC).
  • Google — Email sender guidelines (2024 bulk-sender requirements); Yahoo — Sender requirements & recommendations (2024).

Related OSBR standards