# Avalanche Safety — lean notes

Scope: the leaf "Avalanche Safety" covers transceivers/beacons, probes, shovels, and airbag packs (plus bundled rescue packages of the first three); no sibling catalog.json leaf under supplies>active covers these, so the register keeps all four as one bundle split by product_type.

## Seed
1. Equivalent of the knife-steel-hardness entry: airbag inflation mechanism (cartridge vs electric fan) — looks like a simple spec but is really one side of a cost/weight-vs-flyability trade-off.
2. A watchmaker-type persona would notice that a transceiver's headline "max range" is a best-case marketing number, while "search strip width" (often smaller, from the same spec sheet) is the real precision spec that sets how many passes a slope search needs — and that antenna count doesn't reliably predict it (Pieps dual-antenna beats BCA three-antenna on strip width).

## Sources
- [wiki_transceiver] https://en.wikipedia.org/wiki/Avalanche_transceiver — 457kHz international standard, antenna count — fetched excerpt: "457 kHz... frequency standard... adopted" / "digital transceiver must have at least two antennas, although most modern transceivers have three"
- [wiki_airbag] https://en.wikipedia.org/wiki/Avalanche_airbag — inflation mechanism, inverse segregation, inflated bag volume — fetched excerpt: "200-litre... battery-powered fan... inflate... in around 3.5 seconds"/"canisters... discharged" for flight
- [rei_safetygear] https://web.archive.org/web/20251107185140/https://www.rei.com/learn/expert-advice/avalanche-safety-gear.html — Big Three, cartridge vs fan — fetched excerpt: "Cartridge-style... refilled..."/"Fan-style... up to six times on a full charge"
- [rei_transceiver] https://web.archive.org/web/20260703225239/https://www.rei.com/learn/expert-advice/avalanche-transceiver.html — 3-antenna standard, multiple burial/marking, auto-revert, group check — fetched excerpt: "All modern transceivers use a 3-antenna design... industry standard"/"Most reputable brands offer multiple burial tracking even in their most basic models"/"Automatic revert to transmit mode... secondary avalanche"
- [rei_shovel] https://web.archive.org/web/20260508091158/https://www.rei.com/learn/expert-advice/snow-shovel.html — blade material, grip, hoe mode, shaft length — fetched excerpt: "aluminum predominates. Plastic shovels aren't suited..."/"T-grip... D-grip"/"switch the blade to a 90° angle... hoeing motion"/"Longer, extended shafts... better leverage"
- [wildsnow_shovels] https://wildsnow.com/26885/avalanche-rescue-shovels-overview-2019/ — blade material, extendable handle, hoe feature, blade dimensions, weight, saw — fetched excerpt: "Aluminum, not plastic."/"Extendable handle has become standard, if not mandatory"/"Ortovox Pro Alu... 29 x 22 cm... Weight 794 grams"/"BCA Dozer... 25.4 x 27.9 cm"/"BCA B1... 24.9 x 25.4 cm"/"BCA D2... 947 grams (with saw)"/"BCA-B1... 600 grams" (blade dimensions run 24.9x25.4 to 25.4x27.9cm on this page; 30.5x24.4 is pieps_shovel's figure, not wildsnow's)
- [bca_tracker_s] https://backcountryaccess.com/en-in/p/bca-tracker-s-avalanche-beacon-c2312001 — beacon spec numbers — fetched excerpt: "Max Range 50 meters Search Strip Width 55 meters" + "Three Antenna"
- [bca_tracker4] https://backcountryaccess.com/en-in/p/bca-tracker-4-avalanche-beacon-2027 — feature chart — fetched excerpt: "Motion-sensing auto revert X X" (blank for Tracker S) / "Signal Suppression (SS) and Big Picture (BP) modes" / "Mini USB port for downloadable software updates"
- [bca_probes_cat] https://backcountryaccess.com/en-in/c/rescue-gear/avalanche-probes/ — probe lengths/material/lock — fetched excerpt: "240 CM"/"270 CM"/"300 CM", "Stealth 240 Carbon Avalanche Probe", "Aluminum", "Quick-Lock system"
- [bca_airbags_cat] https://backcountryaccess.com/en-in/c/airbags-backpacks/avalanche-airbags/ — pack volume tiers — fetched excerpt: "BCA Float™ E2-15... E2-25... E2-35... E2-45 Avalanche Airbag"
- [pieps_proips] https://www.pieps.com/en/product/pro-ips/ — dual-antenna flagship spec, multi-burial/group check — fetched excerpt: "Maximum range (m): 70 Search strip width (m): 80... Dual Antenna Signal Processing"/"SCAN FUNCTION... VICTIM SELECTION"/"GROUP CHECK PRO-MODE"
- [pieps_jetforce25] https://www.pieps.com/en/product/jetforce-bt-25/ — fan deployments, pack volume, inflated bag volume — fetched excerpt: "rechargeable battery powers up to four inflations at –20 °C"/"Weight (g): 2.980 Volume (l): 25"/"170 liters: The Jetforce creates a breathing cavity"
- [pieps_iprobe300] https://www.pieps.com/en/product/iprobe-bt-plus-300/ — electronic probe spec — fetched excerpt: "automatically recognizes active transceivers during probing"/"Tubes: 7 Tube diameter (mm): 12.5"/"Safety Marker at 100cm and 150cm"
- [pieps_shovel] https://www.pieps.com/en/product/shovel-t825-pro/ — shovel spec — fetched excerpt: "Blade dimensions (cm): 30.5 x 24.4 x 4.5"/"Weight (g): 825"/"Integrated snow saw... Telescopic function"
- [pieps_home] https://www.pieps.com/en/ — probe material lines — fetched excerpt: "a particularly robust aluminum probe, a lightweight and reliable carbon probe... the smart iPROBE"
- [etsi_en300718] https://cdn.standards.iteh.ai/samples/47952/856433f551f64564a33898b99b00099a/ETSI-EN-300-718-1-V2-1-1-2018-01-.pdf — transceiver standard — fetched excerpt: "specifies technical characteristics and methods of measurements for avalanche beacons operating at 457 kHz"/"frequency error shall not exceed ±80 Hz at 457 kHz"
- [edelrid_en16716] https://edelrid.com/040-downloads/Normen_DE_EN%2016716_PDF.pdf — airbag standard EN 16716 — fetched excerpt: "fully inflated airbag must have a minimum volume of 150 l"/"fully inflated within 5 s... remain in this state for at least 3 min"/"-30°C and +50°C"
- [mammut_manual] https://www.manua.ls/mammut/removable-airbag-system-30/manual — EN 16716-compliant product, corroborates 150L/5s — fetched excerpt: "fill time of approximately 3 to 5 seconds and an inflated volume of 150 liters"/"complies with EN 16716:2017"
- [bca_dozer1tul] https://backcountryaccess.com/en-us/p/dozer-1t-ul-avalanche-shovel-2526 — shovel handle length — fetched excerpt: "Handle & Shaft Extended Length 23.25 in / 59 cm"

## Branches
- product_type=transceiver → then_ask antenna_count/search_strip_width/multiple_burial_resolution/auto_revert/group_check: supported by wiki_transceiver + rei_transceiver + bca_tracker4/pieps_proips, which all treat these as the beacon-specific comparison axes.
- product_type=probe → then_ask length/material/electronic_signal_detection: supported by bca_probes_cat (length/material) and pieps_iprobe300 (electronic detection as a distinct probe tier).
- product_type=shovel → then_ask blade_material/handle_grip/handle_extendable/hoe_mode/blade_area/weight/integrated_snow_saw: supported by rei_shovel and wildsnow_shovels covering all seven as real buying-guide axes with sourced numbers.
- product_type=airbag_pack → then_ask inflation_mechanism/pack_storage_volume/inflated_bag_volume: supported by wiki_airbag + rei_safetygear (mechanism) and bca_airbags_cat/pieps_jetforce25 (both volume numbers).
- airbag_inflation_mechanism skip_if product_type isn't airbag_pack: the facet is meaningless for the other three tools.
- product_type=rescue_package_bundle → then_ask the full transceiver+probe+shovel facet set, makes_irrelevant the three airbag facets: supported directly by rei_safetygear's "The big three essentials are also sold in packages that include the transceiver, probe and shovel together" (no airbag mentioned).

## Noise
- BCA Tracker feature-chart rows "Close proximity indicator", "Mute mode", "Temperature resistant LED display" — constant across Tracker 4/3+/S, not a decision point, left out.
- Pieps Pro IPS rows "IPS interference protection", "Inclinometer", "Ghost Signal Elimination", "Auto Antenna Switch", "Deep Burial Recognition", "Backup Mode" — brand-specific refinements of search_strip_width/multiple_burial_resolution/auto_revert already captured at the facet level; too granular and single-brand to model separately.
- "Bluetooth"/firmware-update connectivity row (BCA USB, Pieps Bluetooth) — convenience feature, not a rescue-outcome differentiator; left out of the facet budget.
- BCA/Pieps "Quick-Lock" probe locking mechanism — near-universal on current probes, no sourced alternative (e.g. twist-lock) found this run to contrast against; left out as a facet.
- Pieps shovel bullet features "special surface coating", "sharpened edges", "pronounced center bars", "rescue slide function", "non-slip tread grooves" — single-brand marketing detail within blade_material/hoe_mode already captured; left out.
- Airbag "Torso Length" sizing filter (BCA) — generic backpack-fit sizing, same as the price/brand exclusion test; left out.
- Airbag deployment handle shape/position, battery-level indicator, self-diagnosis — no sourced cross-brand variation found this run; left out.

## Corrections
- reference `kind` enum: changed `specialist_reviewer`→`specialist_review` (x3) and `enthusiast_wiki`→`enthusiast_community` (carried over from prior pass).
- expanded from an 8-facet stub (2 facets per tool beyond product_type) to 19 facets after the coverage test flagged multiple-burial handling, auto-revert, group check, electronic probes, and five sourced shovel specs (extendable handle, hoe mode, blade area, weight, integrated saw) as real spec-sheet/buyer-guide rows with no facet.
- added airbag_pack_storage_volume and airbag_inflated_bag_volume once a second brand source (pieps_jetforce25) corroborated BCA's own E2-15/25/35/45 liter tiers and Wikipedia's 200L inflated-bag figure.
- fixed cold_start_question for shovel_integrated_snow_saw: validator rejected the "Do you want..." preamble; reworded to "A built-in snow saw too, or not?"

## Corrections (2026-10-26)
- Added `rescue_package_bundle` branch (then_ask the transceiver+probe+shovel facets, makes_irrelevant the three airbag facets) and removed `rescue_package_bundle` from `airbag_inflation_mechanism`'s skip_if_known gate — rei_safetygear confirms bundles are beacon+probe+shovel only, no airbag.
- Added two judgements naming the governing safety standards: ETSI EN 300 718-1 (457kHz, ±80Hz) for transceivers and EN 16716 (150L min inflated volume, 5s inflation, -30°C/+50°C) for airbags.
- Fixed `airbag_inflated_bag_volume`'s range to 150-200L (EN 16716's 150L minimum + wiki_airbag's genuine 200L inflated figure), replacing the contradicted 170L post-deflation "breathing cavity" number.
- Added `shovel_handle_length` facet (59-80cm, pieps_shovel + new bca_dozer1tul source), wired into the shovel and rescue_package_bundle branches and into the other branches' makes_irrelevant lists.
- Folded blade structural reinforcement (ribs/raised sides) into `shovel_blade_material.why_experts_care`, per wildsnow's buyer-guide criterion, rather than adding a standalone facet for a single binary detail.
- Added vocabulary entries for "Airbag pack" and "Rescue package bundle", both used in the primary split with no prior plain-English definition.
- Corrected the wildsnow_shovels blade-dimension sourcing here and in category.json's reference: wildsnow's own range is 24.9x25.4cm to 25.4x27.9cm; 30.5x24.4cm is pieps_shovel's figure, not wildsnow's.
- Rejected: diversifying the single-source ranges (search strip width, probe length, shovel weight) — each endpoint already carries its own distinct brand source, satisfying the two-source-per-range rule; lean budget stops once the coverage test passes rather than hunting a third source per number.