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SRS Tool — Shock Response Spectrum Analyser (view source)

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= Appendix SRS Limit Curves — Normative Reference =
This page documents all predefined SRS limit curves available in the SRS Tool.
Each curve is identified by a '''confidence level''' tag shown next to its name in the interface.
== Confidence level indicators ==
{| class="wikitable" style="width:100%"
! Tag !! Meaning !! What to expect
|-
| style="background:#e8f5e9; color:#1b5e20; font-weight:bold; text-align:center;" | [normative]
| Curve taken '''directly from the published standard''' as an SRS specification.
| Breakpoints are faithful to the document. Use for compliance testing.
|-
| style="background:#fff3e0; color:#e65100; font-weight:bold; text-align:center;" | [approximate]
| Standard defines a '''time-domain waveform''' (half-sine, sawtooth…), '''not''' an SRS.
| The SRS envelope is computed from the pulse shape. For exact results, import the waveform and run compute_srs() on it.
|-
| style="background:#fce4ec; color:#880e4f; font-weight:bold; text-align:center;" | [indicative]
| Levels depend on '''mounting position, equipment mass or mission profile''', or the exact document version was not available.
| Use as a first-pass estimate only. Always verify with the applicable programme document.
|}
All curves use '''Q = 10''' (damping ζ = 5 %) and acceleration units (g).
Between breakpoints, interpolation is '''log-log linear''' (constant dB/octave slope).
----
== Space / Launcher ==
=== NASA GEVS — Protoflight, 2500 g (GSFC-STD-7000B) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#e8f5e9; color:#1b5e20;" | [normative]
|-
| '''Reference''' || NASA GSFC-STD-7000B Rev B (2013)
|-
| '''Application''' || Hardware mounted on primary structure
|}
'''Description:''' Protoflight SRS for hardware mounted on primary structure. The curve rises at +9 dB/oct from 20 Hz, reaching a flat plateau of 2 500 g above 100 Hz. Breakpoints are faithful to the published standard.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 20 || 224
|-
| 100 || 2 500
|-
| 10 000 || 2 500
|}
----
=== NASA GEVS — Protoflight, 1 000 g (GSFC-STD-7000B) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#e8f5e9; color:#1b5e20;" | [normative]
|-
| '''Reference''' || NASA GSFC-STD-7000B Rev B (2013)
|-
| '''Application''' || Hardware mounted on a panel or bracket
|}
'''Description:''' Lower protoflight level for panel- or bracket-mounted hardware. Same +9 dB/oct slope, plateau at 1 000 g. Choose between 2 500 g and 1 000 g based on the mounting position specified in the programme's MTP/ATP.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 20 || 89
|-
| 100 || 1 000
|-
| 10 000 || 1 000
|}
----
=== NASA GEVS — Qualification, 3 750 g (GSFC-STD-7000B) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#e8f5e9; color:#1b5e20;" | [normative]
|-
| '''Reference''' || NASA GSFC-STD-7000B Rev B (2013)
|-
| '''Application''' || Qualification test (1.5 × protoflight 2 500 g level)
|}
'''Description:''' Qualification SRS = 1.5 × protoflight 2 500 g level, per GSFC-STD-7000B. Applied when a dedicated qualification unit is available (as opposed to protoflight testing, which tests the flight unit at a lower margin).
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 20 || 335
|-
| 100 || 3 750
|-
| 10 000 || 3 750
|}
----
=== Ariane 5 — Equipment Bay, Component Level ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || Ariane 5 User's Manual Issue 5 Rev 2 (2016), Annex 2
|-
| '''Application''' || Satellite equipment bay, component level
|}
'''Description:''' Representative SRS at the equipment bay for Ariane 5 missions. Covers separation events (SYLDA, VEB, fairing jettison, etc.). Actual levels depend on satellite integration position — contact Arianespace for flight-specific requirements.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 100 || 100
|-
| 2 000 || 2 000
|-
| 10 000 || 2 000
|}
----
=== Ariane 6 — Component Level ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || Ariane 6 User's Manual Issue 1 Rev 0 (2020)
|-
| '''Application''' || Component level, all payload positions
|}
'''Description:''' Component-level SRS for Ariane 6 missions. Slightly lower than Ariane 5 thanks to the improved fairing and dispenser design. Contact Arianespace for actual flight requirements.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 100 || 80
|-
| 2 000 || 1 600
|-
| 10 000 || 1 600
|}
----
=== VEGA-C — Component Level ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || VEGA-C User's Manual Issue 0 Rev 1 (2022)
|-
| '''Application''' || Small satellite missions, component level
|}
'''Description:''' Component-level SRS for VEGA-C missions. Contact Avio / ESA for actual flight requirements.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 100 || 60
|-
| 2 000 || 1 200
|-
| 10 000 || 1 200
|}
----
=== ECSS-E-ST-10-03C — Protoqualification (représentatif) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || ECSS-E-ST-10-03C (2012)
|-
| '''Application''' || European space programmes, proto-qualification
|}
'''Description:''' Representative proto-qualification SRS for European space programmes. ECSS-E-ST-10-03C defines the methodology and test flow, not a universal level. Actual levels must come from the programme's System Verification Plan (SVP).
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 20 || 50
|-
| 100 || 500
|-
| 2 000 || 2 000
|-
| 10 000 || 2 000
|}
----
== Military / Pyroshock — MIL-STD-810H Method 517 ==
Method 517 (Pyroshock) is one of the few military standards that defines SRS limits '''directly''' — all three curves below are therefore '''[normative]'''.
=== MIL-STD-810H Meth.517 — Near-field (< 0.5 m) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#e8f5e9; color:#1b5e20;" | [normative]
|-
| '''Reference''' || MIL-STD-810H, Method 517.2, Table 517.2-IV
|-
| '''Application''' || Equipment < 0.5 m from the pyrotechnic source
|}
'''Description:''' Pyroshock near-field SRS. Rises at +9 dB/oct from 100 Hz, reaching a flat plateau of 10 000 g above 3 000 Hz. This is the most severe of the three field classifications.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 100 || 61
|-
| 3 000 || 10 000
|-
| 10 000 || 10 000
|}
----
=== MIL-STD-810H Meth.517 — Mid-field (0.5–1.5 m) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#e8f5e9; color:#1b5e20;" | [normative]
|-
| '''Reference''' || MIL-STD-810H, Method 517.2, Table 517.2-IV
|-
| '''Application''' || Equipment 0.5–1.5 m from the pyrotechnic source
|}
'''Description:''' Pyroshock mid-field SRS. Same +9 dB/oct slope, plateau at 1 000 g above 3 000 Hz. 10× lower than near-field (20 dB).
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 100 || 6
|-
| 3 000 || 1 000
|-
| 10 000 || 1 000
|}
----
=== MIL-STD-810H Meth.517 — Far-field (> 1.5 m) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#e8f5e9; color:#1b5e20;" | [normative]
|-
| '''Reference''' || MIL-STD-810H, Method 517.2, Table 517.2-IV
|-
| '''Application''' || Equipment > 1.5 m from the pyrotechnic source
|}
'''Description:''' Pyroshock far-field SRS. Plateau at 100 g above 3 000 Hz. 100× lower than near-field (40 dB).
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 100 || 0.6
|-
| 3 000 || 100
|-
| 10 000 || 100
|}
----
== Military / Mechanical Shock — MIL-STD-810H Method 516 ==
Method 516 defines '''time-domain waveforms''' (half-sine, sawtooth), not SRS limits directly. The SRS envelopes below are computed from those pulses and are therefore '''[approximate]'''. For exact compliance, import the waveform into the SRS Tool and compute the SRS directly.
=== MIL-STD-810H Meth.516.8 — Functional, 40 g half-sine ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || MIL-STD-810H, Method 516.8, Procedure I
|-
| '''Waveform''' || 40 g / 11 ms half-sine
|}
'''Description:''' Functional shock — equipment must operate normally before and after. The standard defines a 40 g, 11 ms half-sine pulse. The SRS envelope peaks near 1/(2τ) ≈ 45 Hz at 2×A = 80 g and flattens to the peak amplitude above.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 80
|-
| 45 || 80
|-
| 200 || 40
|-
| 2 000 || 40
|}
----
=== MIL-STD-810H Meth.516.8 — Crash Hazard, 40 g sawtooth ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || MIL-STD-810H, Method 516.8, Procedure V
|-
| '''Waveform''' || 40 g / 11 ms terminal sawtooth
|}
'''Description:''' Crash hazard — equipment must not become a hazard during a crash. The terminal sawtooth waveform has a broader SRS plateau than a half-sine of the same amplitude.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 60
|-
| 100 || 60
|-
| 500 || 40
|-
| 2 000 || 40
|}
----
=== MIL-STD-810H Meth.516.8 — Bench Handling, 15 g half-sine ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || MIL-STD-810H, Method 516.8, Procedure VI
|-
| '''Waveform''' || 15 g / 11 ms half-sine
|}
'''Description:''' Bench handling — simulates drops and knocks during handling and maintenance. Lower level than functional shock.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 30
|-
| 45 || 30
|-
| 200 || 15
|-
| 2 000 || 15
|}
----
== Military / Naval — MIL-S-901D ==
MIL-S-901D specifies a physical '''machine test''' (Lightweight Shock Machine or floating barge), not an SRS limit. The curves below are '''[indicative]''' envelopes representative of the machine output.
=== MIL-S-901D — Grade A (lightweight, < 136 kg) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || MIL-S-901D (1989), Grade A
|-
| '''Application''' || US Navy — lightweight equipment (< 136 kg)
|}
'''Description:''' High-energy naval shock test for lightweight equipment. Uses the Lightweight Shock Machine (LWSM). Representative SRS envelope of the machine output.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 20 || 100
|-
| 100 || 500
|-
| 2 000 || 2 000
|-
| 10 000 || 2 000
|}
----
=== MIL-S-901D — Grade B (mediumweight, 136–2 268 kg) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || MIL-S-901D (1989), Grade B
|-
| '''Application''' || US Navy — medium-weight equipment (136–2 268 kg)
|}
'''Description:''' Naval shock using the floating barge platform. Lower levels than Grade A due to the larger test article mass and different test rig.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 20 || 50
|-
| 100 || 250
|-
| 2 000 || 1 000
|-
| 10 000 || 1 000
|}
----
== Aviation — RTCA DO-160G Section 7 ==
DO-160G Section 7 defines '''time-domain shock pulses''', not SRS limits. All three curves are '''[approximate]''' envelopes computed from those pulses.
=== DO-160G Sect.7 — Cat. B, Operational (6 g half-sine) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || RTCA DO-160G, Section 7, Category B
|-
| '''Waveform''' || 6 g / 11 ms half-sine
|}
'''Description:''' Aircraft operational shock — in-service turbulence, hard landings, taxiing. The least severe DO-160G shock category.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 12
|-
| 45 || 12
|-
| 200 || 6
|-
| 2 000 || 6
|}
----
=== DO-160G Sect.7 — Cat. C, Bench Handling (15 g half-sine) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || RTCA DO-160G, Section 7, Category C
|-
| '''Waveform''' || 15 g / 11 ms half-sine
|}
'''Description:''' Bench handling shock for avionics — drops, knocks during maintenance. Matches MIL-STD-810H Procedure VI levels.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 30
|-
| 45 || 30
|-
| 200 || 15
|-
| 2 000 || 15
|}
----
=== DO-160G Sect.7 — Cat. D, Crash (20 g) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || RTCA DO-160G, Section 7, Category D
|-
| '''Waveform''' || 20 g equivalent crash pulse
|}
'''Description:''' Crash / emergency landing survivability requirement. Equipment must not create a hazard to occupants during a crash sequence.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 40
|-
| 45 || 40
|-
| 200 || 20
|-
| 2 000 || 20
|}
----
== European Defence ==
=== DEF STAN 00-35 Pt.3 — Category M (Mechanical) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || DEF STAN 00-35 Part 3 Issue 4, Category M
|-
| '''Application''' || UK defence — general mechanical shock
|}
'''Description:''' UK Ministry of Defence standard for general mechanical shock environments. Levels depend on the platform category. Always verify against the Test Schedule (TS) applicable to the programme.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 10 || 25
|-
| 100 || 250
|-
| 2 000 || 1 000
|-
| 10 000 || 1 000
|}
----
=== DEF STAN 00-35 Pt.3 — Category P (Pyrotechnic) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || DEF STAN 00-35 Part 3 Issue 4, Category P
|-
| '''Application''' || UK defence — aircraft store separation (pyrotechnic)
|}
'''Description:''' Pyrotechnic shock for aircraft-delivered stores (bombs, missiles). More severe than Category M. Verify against the applicable Test Schedule.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 100 || 100
|-
| 1 000 || 2 000
|-
| 10 000 || 2 000
|}
----
=== GAM EG-13 — Choc sévère (pyrotechnique) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || DGA GAM EG-13 (2002), Tableau 3, Choc sévère
|-
| '''Application''' || French DGA — severe pyrotechnic shock environment
|}
'''Description:''' French DGA (Direction Générale de l'Armement) standard for severe shock, typically from pyrotechnic devices (ejection seats, weapon release). Verify exact levels in Table 3 of the applicable programme document.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 20 || 40
|-
| 100 || 200
|-
| 1 000 || 2 000
|-
| 10 000 || 2 000
|}
----
=== GAM EG-13 — Choc modéré (mécanique) ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || DGA GAM EG-13 (2002), Tableau 3, Choc modéré
|-
| '''Application''' || French DGA — moderate mechanical shock environment
|}
'''Description:''' French DGA standard for moderate mechanical shock (vehicle impacts, transport drops). Significantly lower levels than the pyrotechnic environment.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 10 || 20
|-
| 100 || 100
|-
| 1 000 || 500
|-
| 5 000 || 500
|}
----
== NATO — STANAG 4370 / AECTP 201 ==
=== STANAG 4370 AECTP 201 — Meth.417 Pyroshock ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fce4ec; color:#880e4f;" | [indicative]
|-
| '''Reference''' || STANAG 4370 AECTP 201, Method 417 (Ed.3, 2009)
|-
| '''Application''' || NATO — pyroshock, severity level 3 (severe platform)
|}
'''Description:''' NATO standardised pyroshock test method (SRS method). The curve shown is representative of severity level 3 (severe platform shock). Actual levels must be drawn from the applicable NATO programme documents.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 100 || 50
|-
| 1 000 || 2 000
|-
| 10 000 || 2 000
|}
----
=== STANAG 4370 AECTP 201 — Meth.403 Mechanical Shock ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || STANAG 4370 AECTP 201, Method 403 (Ed.3, 2009)
|-
| '''Waveform''' || Half-sine pulse, severity level 3
|}
'''Description:''' NATO mechanical shock — Method 403 defines time-domain pulses (half-sine), not SRS directly. The curve shown is an SRS envelope computed from the severity level 3 half-sine waveform.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 50
|-
| 50 || 50
|-
| 500 || 25
|-
| 2 000 || 25
|}
----
== Industrial — IEC 60068-2-27 ==
IEC 60068-2-27 (Test Ea) defines '''half-sine time-domain pulses''', not SRS limits. All curves are '''[approximate]'''.
=== IEC 60068-2-27 — Test Ea, 15 g / 11 ms half-sine ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || IEC 60068-2-27 Ed.3 (2008), Test Ea — 15 g / 11 ms
|-
| '''Application''' || General industrial equipment — standard shock level
|}
'''Description:''' Standard environmental test shock (Test Ea). Widely used for industrial and commercial equipment qualification. 15 g / 11 ms half-sine is the most common combination.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 30
|-
| 45 || 30
|-
| 200 || 15
|-
| 2 000 || 15
|}
----
=== IEC 60068-2-27 — Test Ea, 50 g / 11 ms half-sine ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || IEC 60068-2-27 Ed.3 (2008), Test Ea — 50 g / 11 ms (severe)
|-
| '''Application''' || Industrial equipment — severe shock level
|}
'''Description:''' Severe industrial shock. Used for rugged equipment or harsh installation environments.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 100
|-
| 45 || 100
|-
| 200 || 50
|-
| 2 000 || 50
|}
----
=== IEC 60068-2-27 — Test Ea, 100 g / 6 ms half-sine ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || IEC 60068-2-27 Ed.3 (2008), Test Ea — 100 g / 6 ms
|-
| '''Application''' || Industrial equipment — harsh shock level
|}
'''Description:''' Harsh shock level — short duration (6 ms) shifts the SRS peak to ~83 Hz. Used for equipment exposed to impacts, sudden accelerations, or harsh transport.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 5 || 200
|-
| 83 || 200
|-
| 500 || 100
|-
| 2 000 || 100
|}
----
== Railway — IEC 61373 ==
IEC 61373 defines '''time-domain shock pulses''' for railway equipment. All curves are '''[approximate]'''.
=== IEC 61373 Cat.1 Class B — Railway, Vehicle Body ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || IEC 61373 Ed.2 (2010), Category 1 Class B
|-
| '''Application''' || Equipment mounted on the vehicle body (interior)
|}
'''Description:''' Functional shock for body-mounted railway equipment. IEC 61373 defines a 3 g / 30 ms half-sine. The long duration (30 ms) places the SRS peak at only ~16 Hz — the lowest peak frequency of all curves in the library.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 2 || 6
|-
| 16 || 6
|-
| 200 || 3
|-
| 2 000 || 3
|}
----
=== IEC 61373 Cat.1 Class A — Railway, Bogie-Mounted ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || IEC 61373 Ed.2 (2010), Category 1 Class A
|-
| '''Application''' || Equipment mounted on the bogie (running gear)
|}
'''Description:''' Bogie-mounted equipment is directly exposed to rail irregularities and rail joints. Significantly higher levels than Class B (vehicle body). IEC 61373 defines a time-domain pulse, not an SRS.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 2 || 15
|-
| 16 || 15
|-
| 200 || 8
|-
| 2 000 || 8
|}
----
=== IEC 61373 Cat.2 — Railway, Under-Body Mounted ===
{| class="wikitable"
! Field !! Value
|-
| '''Tag''' || style="background:#fff3e0; color:#e65100;" | [approximate]
|-
| '''Reference''' || IEC 61373 Ed.2 (2010), Category 2
|-
| '''Application''' || Under-body mounted equipment, axle box area
|}
'''Description:''' Most severe shock category in IEC 61373. Under-body equipment (including axle-box area) is exposed to the highest shock levels on a railway vehicle.
{| class="wikitable" style="text-align:center;"
! Frequency (Hz) !! Level (g)
|-
| 2 || 50
|-
| 16 || 50
|-
| 200 || 25
|-
| 2 000 || 25
|}
----
== Summary table ==
{| class="wikitable sortable" style="width:100%; font-size:90%;"
! Standard !! Sector !! Tag !! Peak level !! Freq. range
|-
| NASA GEVS 2500 g || Space || style="background:#e8f5e9; color:#1b5e20;" | normative || 2 500 g || 20–10 000 Hz
|-
| NASA GEVS 1000 g || Space || style="background:#e8f5e9; color:#1b5e20;" | normative || 1 000 g || 20–10 000 Hz
|-
| NASA GEVS 3750 g (Qual.) || Space || style="background:#e8f5e9; color:#1b5e20;" | normative || 3 750 g || 20–10 000 Hz
|-
| Ariane 5 Equipment Bay || Space || style="background:#fce4ec; color:#880e4f;" | indicative || 2 000 g || 100–10 000 Hz
|-
| Ariane 6 || Space || style="background:#fce4ec; color:#880e4f;" | indicative || 1 600 g || 100–10 000 Hz
|-
| VEGA-C || Space || style="background:#fce4ec; color:#880e4f;" | indicative || 1 200 g || 100–10 000 Hz
|-
| ECSS-E-ST-10-03C Protoqual. || Space || style="background:#fce4ec; color:#880e4f;" | indicative || 2 000 g || 20–10 000 Hz
|-
| MIL-STD-810H M517 Near-field || Military / Pyro || style="background:#e8f5e9; color:#1b5e20;" | normative || 10 000 g || 100–10 000 Hz
|-
| MIL-STD-810H M517 Mid-field || Military / Pyro || style="background:#e8f5e9; color:#1b5e20;" | normative || 1 000 g || 100–10 000 Hz
|-
| MIL-STD-810H M517 Far-field || Military / Pyro || style="background:#e8f5e9; color:#1b5e20;" | normative || 100 g || 100–10 000 Hz
|-
| MIL-STD-810H M516 Functional 40 g || Military / Mech || style="background:#fff3e0; color:#e65100;" | approximate || 80 g (2×A) || 5–2 000 Hz
|-
| MIL-STD-810H M516 Crash 40 g || Military / Mech || style="background:#fff3e0; color:#e65100;" | approximate || 60 g || 5–2 000 Hz
|-
| MIL-STD-810H M516 Bench 15 g || Military / Mech || style="background:#fff3e0; color:#e65100;" | approximate || 30 g || 5–2 000 Hz
|-
| MIL-S-901D Grade A || Military / Naval || style="background:#fce4ec; color:#880e4f;" | indicative || 2 000 g || 20–10 000 Hz
|-
| MIL-S-901D Grade B || Military / Naval || style="background:#fce4ec; color:#880e4f;" | indicative || 1 000 g || 20–10 000 Hz
|-
| DO-160G Cat. B 6 g || Aviation || style="background:#fff3e0; color:#e65100;" | approximate || 12 g || 5–2 000 Hz
|-
| DO-160G Cat. C 15 g || Aviation || style="background:#fff3e0; color:#e65100;" | approximate || 30 g || 5–2 000 Hz
|-
| DO-160G Cat. D 20 g || Aviation || style="background:#fff3e0; color:#e65100;" | approximate || 40 g || 5–2 000 Hz
|-
| DEF STAN 00-35 Cat. M || European Defence || style="background:#fce4ec; color:#880e4f;" | indicative || 1 000 g || 10–10 000 Hz
|-
| DEF STAN 00-35 Cat. P || European Defence || style="background:#fce4ec; color:#880e4f;" | indicative || 2 000 g || 100–10 000 Hz
|-
| GAM EG-13 Choc sévère || European Defence (DGA) || style="background:#fce4ec; color:#880e4f;" | indicative || 2 000 g || 20–10 000 Hz
|-
| GAM EG-13 Choc modéré || European Defence (DGA) || style="background:#fce4ec; color:#880e4f;" | indicative || 500 g || 10–5 000 Hz
|-
| STANAG 4370 AECTP-201 M417 || NATO || style="background:#fce4ec; color:#880e4f;" | indicative || 2 000 g || 100–10 000 Hz
|-
| STANAG 4370 AECTP-201 M403 || NATO || style="background:#fff3e0; color:#e65100;" | approximate || 50 g || 5–2 000 Hz
|-
| IEC 60068-2-27 15 g / 11 ms || Industrial || style="background:#fff3e0; color:#e65100;" | approximate || 30 g || 5–2 000 Hz
|-
| IEC 60068-2-27 50 g / 11 ms || Industrial || style="background:#fff3e0; color:#e65100;" | approximate || 100 g || 5–2 000 Hz
|-
| IEC 60068-2-27 100 g / 6 ms || Industrial || style="background:#fff3e0; color:#e65100;" | approximate || 200 g || 5–2 000 Hz
|-
| IEC 61373 Cat.1 Class B || Railway || style="background:#fff3e0; color:#e65100;" | approximate || 6 g || 2–2 000 Hz
|-
| IEC 61373 Cat.1 Class A || Railway || style="background:#fff3e0; color:#e65100;" | approximate || 15 g || 2–2 000 Hz
|-
| IEC 61373 Cat.2 Under-body || Railway || style="background:#fff3e0; color:#e65100;" | approximate || 50 g || 2–2 000 Hz
|}
----
== How the SRS Tool uses these curves ==
# Select a curve in the '''Pass/Fail''' tab.
# The tool interpolates the curve at the same frequency resolution as the measured SRS using log-log linear interpolation.
# Margin is computed point-by-point: '''Margin (dB) = 20 × log₁₀(limit / SRS)'''
** Positive margin → SRS is below the limit ('''PASS''' at that frequency)
** Negative margin → SRS exceeds the limit ('''FAIL''' at that frequency)
# The overall result is PASS only if the margin is positive at '''all''' frequencies.
== Adding a custom curve ==
You can import your own limit curve via a two-column CSV file (frequency Hz, level g) using the '''Load CSV''' button in the Pass/Fail tab. The SRS Tool applies the same log-log interpolation as built-in curves.
[[Category:SRS Tool]]
[[Category:Test Standards]]


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