> ## Documentation Index > Fetch the complete documentation index at: https://docs.orbit.devotel.io/llms.txt > Use this file to discover all available pages before exploring further. # Voice pre-send gate chain: the order outbound calls are evaluated > The fixed order of pre-send checks on the outbound voice dial path — emergency short-code, TCPA federal window, FCC AI-voice consent, fraud and DNO guards, per-country rate window, and STIR/SHAKEN attestation — with a precedence table, tenant-override answers, and how to read which gate fired. # Voice pre-send gate chain An outbound voice call passes a chain of pre-send checks before any SIP leaves the platform. This page is the single map of that chain: the **order** the gates evaluate in, which ones you can turn off, and how to read a rejection back to the exact gate that fired. It is a routing page — it maps gates to their deep pages rather than re-explaining them. The chain runs on the outbound-dial path itself. A campaign launch, a dialer send, an ad-hoc dashboard dial, and a customer-trunk origination all take the same checks in the same order. ## 1. The canonical chain — order of evaluation The gates fire in this order on every outbound voice call: 1. **Emergency short-code reject** — platform-global, no toggle. If the destination resolves to an emergency short code (911 / 112 / 999 / 000\), the call is refused first, before any other gate runs. → `422 EMERGENCY_CALLING_NOT_SUPPORTED`. Deep page: [Troubleshooting: voice destination blocks → Emergency short codes](/troubleshooting/voice-destination-blocks), code in the [error codes reference](/reference/error-codes). 2. **TCPA federal dialing window** for campaign/dialer US (+1) voice, and the **tenant opt-in quiet-hours gate** for ad-hoc dials. The federal 8 AM–9 PM recipient-local window is the one compliance control the platform owns outright: no opt-out, fail-closed. → `422 TCPA_FEDERAL_DIALING_WINDOW_BLOCKED` (federal), `TCPA_DIALING_WINDOW_BLOCKED` (your opt-in gate), `TCPA_STATE_DIALING_WINDOW_BLOCKED` (state overlay). Deep pages: [TCPA federal voice guard](/concepts/tcpa-federal-voice-guard), [US state calling windows](/compliance/state-calling-windows), [send gates → quiet hours](/compliance/send-gates). 3. **FCC AI-voice written-consent gate** — runs **after** the federal window and **before** any billing hold or media step. If the call is classified `synthetic` or `cloned` and no prior express written consent is on record, the call blocks. Human-voice calls short-circuit as no-ops. → `422 FCC_AI_VOICE_WRITTEN_CONSENT_REQUIRED`. Deep page: [FCC 24-17 — written consent for AI voices](/compliance/fcc-ai-voice-consent-guard). 4. **Fraud-velocity guard**, then the **DNO caller-id reject**. The fraud-velocity guard blocks premium-rate destination prefixes and enforces per-tenant rate and daily-spend caps. The DNO guard runs after the caller-id (`from`) is resolved and rejects a calling-party number that matches a Do-Not-Originate entry. → `VOICE_BLOCKED_DESTINATION` / `VOICE_DAILY_SPEND_CAP` / `VOICE_RATE_LIMITED` (fraud guard), `422 VOICE_DNO_BLOCKED` (DNO). Deep page: [Troubleshooting: voice destination blocks → DNO](/troubleshooting/voice-destination-blocks). 5. **Trunk caller-id reject** — on a customer SIP trunk INVITE, the presented caller-id must be in the trunk's allow-list or the org's DID list. → `VOICE_CALLER_ID_REJECTED` (403 on the trunk path). Deep page: [Troubleshooting: voice destination blocks → Trunk caller-id](/troubleshooting/voice-destination-blocks). 6. **Per-country rate window** — a per-destination-country sliding-window cap. → `429 VOICE_COUNTRY_RATE_LIMITED`. Deep page: [Troubleshooting: voice destination blocks → Per-country rate window](/troubleshooting/voice-destination-blocks). 7. **STIR/SHAKEN attestation assignment** — **not a gate.** The A/B/C attestation level is resolved at the same moment as the pre-send checks and stamped onto the call record for reporting. It never blocks or reroutes a call. Deep page: [STIR/SHAKEN attestation posture](/compliance/attestation). Order matters for triage: a call refused at step 1 never reached step 7\. When you read a rejection, the gate **nearest step 1 that fired** is the one to fix first — later gates never got a chance to run. ## 2. Precedence table — gate, trigger, code, can you turn it off | # | Gate | Trigger shape | Error code | Tenant overridable? | Documentation | | - | ---------------------------------- | -------------------------------------------------------------------------- | -------------------------------------------------------------------------- | ----------------------------------------------------- | -------------------------------------------------------------------------------------- | | 1 | Emergency short-code | Destination resolves to 911 / 112 / 999 / 000 | `422 EMERGENCY_CALLING_NOT_SUPPORTED` | **No** — platform-global, no toggle | [Error codes reference](/reference/error-codes) | | 2 | TCPA federal dialing window | Campaign/dialer voice to a +1 recipient outside 8 AM–9 PM recipient-local | `422 TCPA_FEDERAL_DIALING_WINDOW_BLOCKED` | **No** — the sole platform-global compliance gate | [TCPA federal voice guard](/concepts/tcpa-federal-voice-guard) | | 2 | Tenant opt-in quiet-hours gate | Ad-hoc dial outside your configured voice window | `TCPA_DIALING_WINDOW_BLOCKED` | **Yes** — per-channel toggle in quiet-hours settings | [Send gates → quiet hours](/compliance/send-gates) | | 2 | State mini-TCPA overlay | State statute window or banned day for the recipient's state | `TCPA_STATE_DIALING_WINDOW_BLOCKED` | **No** — composes with the federal floor | [US state calling windows](/compliance/state-calling-windows) | | 3 | FCC AI-voice written consent | `synthetic` or `cloned` voice classification, no written consent on record | `422 FCC_AI_VOICE_WRITTEN_CONSENT_REQUIRED` | **No** — fails closed on missing consent | [FCC 24-17 — written consent for AI voices](/compliance/fcc-ai-voice-consent-guard) | | 4 | Fraud-velocity guard | Premium-rate destination prefix, per-tenant rate/daily-spend cap | `VOICE_BLOCKED_DESTINATION`, `VOICE_DAILY_SPEND_CAP`, `VOICE_RATE_LIMITED` | **No** — technical safety, not tenant-tunable | — | | 4 | DNO caller-id reject | `from` matches a Do-Not-Originate entry/prefix | `422 VOICE_DNO_BLOCKED` | **Yes** — per-org DNO override in voice settings | [Troubleshooting → DNO](/troubleshooting/voice-destination-blocks) | | 5 | Trunk caller-id reject | INVITE caller-id outside trunk allow-list and org DID list | `VOICE_CALLER_ID_REJECTED` (403) | **Yes** — the trunk's `allowedCallerIds` list | [Troubleshooting → Trunk caller-id](/troubleshooting/voice-destination-blocks) | | 6 | Per-country rate window | Per-destination-country sliding-window cap exceeded | `429 VOICE_COUNTRY_RATE_LIMITED` | **Yes** — tenant-configured per-country window/limits | [Troubleshooting → Per-country rate window](/troubleshooting/voice-destination-blocks) | | 7 | STIR/SHAKEN attestation assignment | Resolved A/B/C level stamped onto the call | (none — not a gate) | **Yes** — your attestation policy; reporting only | [STIR/SHAKEN attestation posture](/compliance/attestation) | ## 3. Which gate fired — read the 422 body and the audit log Every gate writes its **own distinct error code** onto the rejection, so disambiguation is mechanical, not interpretive. **Read the response body.** The `error.code` field in the JSON body names the gate that fired. Match the code against the precedence table above. A refusal at step 2 returns a TCPA code; a refusal at step 6 returns `429 VOICE_COUNTRY_RATE_LIMITED`; the two never overlap. Codes with `FEDERAL` in the name belong to the platform's hard guard; codes without it belong to your own tenant-side configuration. For the FCC gate specifically, the 422 payload also carries a `reason` (`no_written_consent_on_record`, `tenant_consent_schema_missing`, or `consent_lookup_error`) and a hint describing the consent-row shape to add. **Cross-check in the audit log.** Each gate also writes an audit entry at the moment it blocks, so you can correlate a user's report against the recorded event. Filter your [audit log](/guides/audit-log) (`Settings → Audit log`) by: * The **recipient number** (redacted) and the **call path** (campaign, ad-hoc dial, trunk origination) to isolate the attempt. * The **machine event code** — e.g. `voice.fcc_ai_consent_blocked` for the AI-consent gate — so you can separate one gate's blocks from another even when two gates fired on the same recipient in one session. * The **error code** — every block event carries the same code the API returned, so the audit entry and the 422 body agree on which gate fired. The audit log is append-only, so the record survives whatever happens to the request upstream — a blocked call still leaves its gate's audit row even when the caller retries or abandons. **When the result looks wrong**, capture the full error body (code + `details`), the destination and presented caller-id in E.164, the call path, and your organization id before escalating — [Troubleshooting: voice destination blocks](/troubleshooting/voice-destination-blocks) ends with that capture checklist. ## 4. Where the FCC AI-voice consent gate fits The FCC AI-voice written-consent gate sits **after** the federal TCPA dialing-window guard and **before** the billing hold — internal order, fixed by the platform: 1. **After the federal window.** The federal 8 AM–9 PM recipient-local hard guard always runs first; the FCC gate layers on top of it and never relaxes its outputs. 2. **Before any billing hold, media room, or dispatch.** A blocked AI / cloned-voice call never burns a billing hold, never opens a media path, and never touches the disposition lock. Within the same step, the classifier resolves `human`, `synthetic`, or `cloned` from the call's request `metadata` (`voice_content_type` → `voice_cloned_model_id` → `voice_agent_id` / `agent_id` → `tts_text` / `tts_body`); a `human` verdict short-circuits the consent lookup entirely. The precedence table and worked examples live on the gate's own page: [FCC 24-17 — written consent for AI voices](/compliance/fcc-ai-voice-consent-guard). ## 5. Fail-open vs fail-closed — per gate The failure posture of each gate (what happens when the gate itself cannot resolve its input) is deliberate and asymmetric: | Gate | Posture | Why | | ------------------------------ | ------------------------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------- | | Emergency short-code | Block is unconditional once matched | The destination itself is the problem; no failure mode to degrade | | TCPA federal window | **Fail closed** — an unresolvable recipient timezone blocks the call | Without a timezone the platform cannot prove the dial is inside the federal window, and the statutory exposure is $500–$1,500 per call | | Tenant opt-in quiet-hours gate | **Fail open** — an unresolvable timezone defaults to allow (`skip`) | A false refusal on your own configuration is worse than a false pass for a gate you own | | FCC AI-voice consent | **Fail closed** — missing consent schema or a lookup error blocks | At the same statutory floor, a fail-open would silently treat AI voice as compliant whenever the database hiccups | | DNO caller-id reject | **Fail open** — a DB error on the org-settings lookup falls back to the env baseline | A transient database blip must not black-hole every outbound call on a gate whose list is usually empty | | BAA (HIPAA) send gate | **Fail closed** — a gate DB error keeps sends blocked | The gate guards PHI, so it cannot allow a transmission it cannot verify | The asymmetry rule is consistent: controls the platform owns at a statutory floor (federal window, FCC consent, BAA) fail closed, because a false pass is the expensive error. Controls you own (your quiet-hours gate, your DNO override) fail open, because a false refusal is the expensive error. The same split is the reason the federal window carries no `skip` toggle while your own quiet-hours gate ships with one. ## See also * [TCPA federal voice guard](/concepts/tcpa-federal-voice-guard) — the one hard federal dialing-window gate * [FCC 24-17 — written consent for AI voices](/compliance/fcc-ai-voice-consent-guard) — the AI/cloned-voice consent check and its ordering * [Troubleshooting: voice destination blocks](/troubleshooting/voice-destination-blocks) — per-code fixes for the non-TCPA pre-flight rejects * [Send gates](/compliance/send-gates) — quiet hours, DNC, RND, RMD, BAA, emergency stop * [US state calling windows](/compliance/state-calling-windows) — the mini-TCPA state overlay table * [STIR/SHAKEN attestation posture](/compliance/attestation) — the A/B/C posture that is resolved, not gated, at send time * [Audit log](/guides/audit-log) — where every gate's block event lives * [Error codes reference](/reference/error-codes) — the full catalog this page triages