Understanding SCIF & SAPF Security — ICD 705, UL 2050, RED/BLACK

01 The basics

A SCIF is a result, not a product.

A Sensitive Compartmented Information Facility is an area an Accrediting Official has accredited for Sensitive Compartmented Information. Walls, doors, alarms, access control, acoustics and procedures are all evidence — and nothing is “ICD 705 certified” until the facility itself is accredited against its approved design.

Physical

The perimeter resists and shows evidence of penetration; doors, locks and penetrations meet the Tech Spec; speech does not leave the room.

Evidence As-builts, penetration details, photo record, door schedule, acoustic test data

Technical

Intrusion detection, access control, telecommunications and emanations risks are controlled — and proven by test.

Evidence UL 2050 certificate, IDS acceptance tests, encryption certificates, telecom baseline, CTTA review

Procedural

People run the space correctly every day — entry, visitors, combinations, end-of-day checks and emergencies.

Evidence SOP, emergency plan, Construction Security Plan, SF 701/702 checks

Four ways classified information is protected

Start Here module

Attribute	SCIF	SAPF	NISPOM open storage area	GSA-approved container
Protects	SCI	Special Access Program information	Collateral classified (contractor)	Collateral classified; SCI when inside a closed-storage SCIF
Governing documents	ICD 705, ICS 705-1/-2, IC Tech Spec; DoDM 5105.21 in DoD	DoDM 5205.07 (17 Jan 2025), built to equivalent Tech Spec criteria	32 CFR 117.15; 32 CFR 2001.53 & 2001.43	32 CFR 2001.43; DoD Lock Program specs
Who approves	IC element Accrediting Official (DIA for most DoD & DoD contractors)	SAPF Accrediting Official (SAPF-AO)	DCSA approves the space and the IDS before installation	Container must be GSA-approved; supplemental controls per 2001.43
IDS installation	UL 2050 Extent 3 (Tech Spec 7.A.2.b)	UL 2050 Extent 3 (DCSA SAP checklist)	Extent 3 baseline; Extent 5 only with CSA approval	No IDS sensors on the container itself
Alarm response (TS/SCI)	Closed storage 15 min; open storage 15 min with SID, 5 min without	Same as SCIF	TS open storage 15 min with SID, 5 min without	TS: 2-hour checks, or IDS with 15-min response, or SID + FF-L-2740 lock

Published baselines; many items are left to AO or CSA determination, and exceeding a standard requires a waiver. A DCSA-approved open storage area is not a SCIF, and moving SAP into a SCIF (or SCI into a SAPF) requires a co-use agreement first.

02 Interactive SCIF Explorer

Walk through a SCIF suite, one requirement at a time.

Select any numbered point to see what it is, the numbers that matter and a common mistake that fails inspections. Turn on X-ray to see wall layers and hidden cabling, or press Tour.

03 Security-in-Depth & nested access

Detection starts long before the SCIF wall.

Security-in-Depth (SID) is the credit a SCIF earns for the protection around it. The IC Tech Spec lists primary means such as these — and SID is mandatory outside the U.S. It can change alarm response times and construction, but only when the AO documents it.

Installation or compound (military, embassy, U.S. Government or contractor) with a dedicated U.S. response force
Controlled building with separate access control, alarms and elevator controls
Alarmed, access-controlled office space surrounding the SCIF
Fenced compound with access-controlled vehicle or pedestrian gates

The one-way rule. Higher access may pass into lower areas; lower never passes into higher. Clearance is not access — need-to-know is decided separately — and UFC 4-010-05 adds that entry into a lower security area cannot be through a higher one.

Each boundary is controlled independently. Inside a SCIF, compartmented areas get their own access control — but no independent alarm system and no spin-dial locks (Tech Spec 2.C.4); the SCIF’s IDS covers them.

Lab 01 Access control

Higher can go lower. Lower can’t go higher.

Every boundary is controlled on its own. A credential that opens an outer door never opens an inner one, peer compartments don’t open each other, and a clearance is not the same thing as access.

1 Pick a credential Visitorescorted · no clearance Building badgetenant employee Secret collateralcleared · on area list SCI indoctrinatedno compartment briefings SCI + Compartment Abriefed into A SCI + Compartment Bbriefed into B

2 Try a door

You are: on the street

Pick a credential, then try a door.

Start outside on the street. Doors must be passed in order, one boundary at a time.

Clearance ≠ access

Getting through a door takes the right clearance, formal access to that program, and a need-to-know. IDS and access control codes go only to SCI-indoctrinated people with a need to know.

Two technologies at the SCIF

An automated access control system must use at least two technologies (badge, PIN, biometric). It isn’t approved for securing an unoccupied SCIF: that’s the combination lock plus an armed IDS.

Compartmented areas

A compartmented area separates compartments or programs inside a SCIF. The AO approves it with the CA Program Manager’s concurrence. No spin-dial combination locks go on CA doors, and no independent alarm system is installed in a CA (Tech Spec 2.C.4).

Conceptual model

Anti-passback and separate alarm areas for the open storage area and the SCIF are shown to illustrate layered control. They’re site-configured features, not quoted requirements (whether both areas share one panel is an AO/CSA decision); your AO-approved design and SOP set the real rules.

04 Accreditation roadmap

Paper first. Then drywall.

SCIF projects commonly stumble on sequence: contracts awarded before the Construction Security Plan is approved, penetrations added after the TEMPEST review, walls closed before the photo record. Step through who produces — and who approves — each deliverable.

Lab 02 Accreditation

From sponsor to accreditation

Six phases, who produces what, who signs, and where projects usually go wrong. Use the arrow keys to move between phases.

Phase 2 of 6

Planning and pre-design

Decide what kind of SCIF this is and document the risk. Those choices drive wall type, alarm response, acoustics and TEMPEST review.

Deliverables

Concept approval (DoD SCIF)
Risk assessment and Security-in-Depth documentation
Pre-Construction Checklist
TEMPEST Checklist / addendum submitted during planning for the initial CTTA review

Who produces

Command or sponsor (concept request)
AO and SSM (risk assessment)
Project team and SSM (checklists)

Who approves

Service CSA / senior intelligence official (DoD concept approval)
AO; the CTTA reviews TEMPEST inputs

Integrator / GC tasks

Profile the SCIF: closed vs. open storage, secure working area, continuous operations, SID available?
Map discussion rooms and amplified-audio rooms to Sound Group 3 or 4
List every system crossing the perimeter: power, fire alarm, sprinkler, HVAC, IDS, ACS, CCTV, phone, LAN, fiber

Typical traps

Exceeding a standard “to be safe” without a waiver; any waiver removes mandatory reciprocity
Planning RF shielding late; retrofits cost significantly more
Assuming SID and a 15-minute response for open storage

Phase 3 of 6

Design

Turn the profile into drawings, a Construction Security Plan and a Fixed Facility Checklist, with the CTTA’s countermeasure recommendations built in.

Deliverables

Design concept and final design drawings: wall types, door schedule, penetration schedule
Construction Security Plan (CSP)
Fixed Facility Checklist (FFC), pre-construction sections as the AO requires
TEMPEST Countermeasures Review recommendations incorporated

Who produces

Architect-engineer / designer of record (drawings)
SSM, in consultation with the AO (CSP)
SSO / SSM with A-E and integrator input (FFC)
CTTA (countermeasure recommendations)

Who approves

AO approves the design concept, CSP and final design before construction starts

Integrator / GC tasks

UL 2050 Extent 3 IDS design; PCU and sensor cabling inside the perimeter
UL 634 Level II high-security switch plus motion on every perimeter door
Access control with two technologies; fail-secure UL 1034 strikes coordinated with FF-L-2890 hardware
Single, labeled cable entry point; RED/BLACK per the CTTA
Early life-safety review with the AHJ: egress, delayed egress, rated acoustic doors

Typical traps

“Build to ICD 705” instead of building to the approved drawings
Handling SCIF drawings like ordinary construction documents
Discussion or VTC rooms designed to Sound Group 3

Phase 4 of 6

Procurement and construction

No contract award without an approved CSP. Then build with site security, surveillance as the AO requires, and a photo record of everything that gets covered.

Deliverables

Approved CSP in hand before award
SSM periodic inspection reports; construction surveillance technician (CST) logs where the AO requires CSTs
Photographic record of penetrations, doors and wall assemblies
Field change log with SSM / AO concurrence

Who produces

General contractor and trades
SSM (inspections); CSTs and cleared escorts as required

Who approves

AO (CSP, deviations); the SSM reports CSP violations to the AO within 3 business days

Integrator / GC tasks

U.S. companies using U.S. citizens (U.S. persons allowed with mitigations); IDS installed by U.S. citizens
Long-lead buyout: STC-rated door assemblies, FF-L-2890 / FF-L-2740 hardware, duct silencers
Pre-cover hold point: inspect and photograph in-wall and above-ceiling work before board closes
Staggered joints, sealant top and bottom, finish true floor to true ceiling

Typical traps

Awarding before the CSP is approved
Perimeter walls that stop at the drop ceiling
Untracked field changes and no photo record of concealed work
Adding a penetration after the shield test

Phase 5 of 6

Testing and inspection

Prove it works, then prove it on paper. Inspectors can’t see inside a finished wall, so the test data and documents carry the case.

Deliverables

IDS acceptance test results and UL 2050 certificate
Acoustic verification: audio or instrumented test per the AO
TEMPEST / RF testing where required; TSCM as required
Final FFC and TEMPEST addendum with no “TBD” items; as-builts, penetration log, photos

Who produces

Integrator (IDS tests, certificate, spec sheets, encryption certificate)
Acoustic and shielding test providers
USG TSCM team
SSO / SSM assemble the package

Who approves

AO or designee inspects before accreditation

Integrator / GC tasks

Motion walk test: alarm on at least 3 of every 4 trials
High-security switch alarms before the door opens past its own thickness
Tamper tests on every cover; verify 24 hours of backup power
Deliver IDS spec sheets, zone map and test records

Typical traps

Missing IDS paperwork (UL 2050 certificate, NIST encryption certificate, test results)
Unresolved TBD items on the final FFC
IDS not UL 2050 certificated when the AO expects it

Phase 6 of 6

Accreditation and operations

“Accreditation is the beginning of a life-cycle process”: continuous monitoring, periodic re-evaluation and documentation reviews.

Deliverables

Letter of accreditation and SCIF repository entry
Standard operating procedures and emergency plan (plus a catastrophic failure plan in DoD)
IDS and access control records; semi-annual IDS test records
Re-evaluation at least every 5 years; FFC page changes when systems change

Who produces

SSO / CSSO (SOPs, plans, self-inspections)
Integrator (maintenance, testing)

Who approves

AO issues accreditation; the CSA ensures periodic re-evaluations happen

Integrator / GC tasks

Semi-annual IDS testing
Start repairs within 4 hours of a trouble signal
Maintenance by TOP SECRET-cleared or escorted technicians
Keep false alarms to 1 or fewer per 30 days per IDS partition

Typical traps

Major modifications or storage-mode changes trigger re-accreditation
Bringing SAP into a SCIF without a co-use agreement
Treating a waiver as free: it removes the SCIF from mandatory reciprocal use

Phase 1 of 6

05 Perimeter, penetrations & acoustics

True floor to true ceiling — and nothing sneaks through.

The perimeter has two jobs: resist forced entry to the degree the storage mode requires, and show visual evidence of any surreptitious penetration. Every duct, pipe and conduit that crosses it is a designed exception.

Lab 03 Perimeter construction

Tech Spec wall types, layer by layer

The IC Tech Spec (Chapter 3.C, Figures 1–3) gives three perimeter wall details. Wall A is the standard; Walls B and C add a forced-entry layer for open storage without Security-in-Depth.

Serves

Closed storage
Secure Working Area
Continuous operation
Open storage with SID

Designed for Sound Group 3 (STC 45).

Every wall: finished and painted from true floor to true ceiling, so any cut or patch is visible on inspection.

1
⅝″ gypsum wallboard, 1 layer
Uncontrolled side. The wall uses three layers of ⅝″ GWB in total: one outside, two on the controlled side.
2
Studs and track
3⅝″-wide 16-gauge metal studs or wood 2×4s on a 16″ o.c. layout (the figure note reads “no less than 16″ on center”). 16-gauge continuous track top and bottom, anchors at 32″ o.c. maximum, bedded in a continuous bead of acoustical sealant.
3
Acoustic fill
3½″ (89 mm) sound attenuation material, fastened to prevent sliding.
4–5
⅝″ GWB, 2 layers
Controlled (SCIF) side, mounted so seams don’t align. Top and bottom sealed with acoustic sealant where the wall meets the slab.

Serves

Open storage without SID

Same GWB, stud, track, fill and sealant details as Wall A, plus a forced-entry layer.

Every wall: finished and painted from true floor to true ceiling, so any cut or patch is visible on inspection.

1
⅝″ gypsum wallboard, 1 layer
Uncontrolled side.
2–3
Studs, track and acoustic fill
Same as Wall A: 16-gauge studs, 16-gauge continuous track with anchors at 32″ o.c. maximum in acoustical sealant, 3½″ fastened acoustic fill.
4
Expanded metal
¾″ mesh, #9 (10-gauge) expanded metal affixed to the interior side of all SCIF perimeter wall studs. Spot-welded every 6″ along each vertical stud and at ceiling and floor; hardened screws with 1″ washers or hardened clips may be used instead of welding.
5–6
⅝″ GWB, 2 layers
Controlled side, staggered joints, finished and painted true floor to true ceiling.

Serves

Open storage without SID

Still three layers of GWB, but two go on the uncontrolled side and one covers the plywood.

Every wall: finished and painted from true floor to true ceiling, so any cut or patch is visible on inspection.

1–2
⅝″ gypsum wallboard, 2 layers
Uncontrolled side.
3–4
Studs, track and acoustic fill
16-gauge studs (the plywood fastens to them), 16-gauge continuous track with anchors at 32″ o.c. maximum in acoustical sealant, 3½″ fastened acoustic fill.
5
½″ plywood (minimum)
Affixed 8′ vertical by 4′ horizontal to 16-gauge studs with glue and #10 steel tapping screws at 12″ o.c. Must be fire-retardant treated in buildings required to be noncombustible (UFC 3-4.1).
6
⅝″ GWB, 1 layer
Controlled side, over the plywood. Finished and painted true floor to true ceiling.

Existing masonry

An existing brick, concrete or block wall equal to the perimeter standard may be used, pending AO approval.

Going to STC 50

UFC 4-010-05 associates STC 50 with four GWB layers (two each side) and allows one layer of factory-laminated GWB meeting ASTM C1766 to enhance attenuation.

Security detail, not a fire assembly

The Tech Spec figures aren’t rated assemblies. UFC tells designers to make them comply with the building code. RF foil or foil-backed GWB goes in only when the CTTA recommends it.

96 sq in

Ducts & vents

Openings over 96 sq in that penetrate the perimeter get permanently fixed ½-in steel bars 6 in on center (or approved baffles) — not required if one dimension is under 6 in — plus an inspection port.

1 entry

Single point of utility entry

Utilities should enter at one designed location. Other areas’ utilities do not transit the SCIF unless mitigated with AO approval.

0 open

Spare conduit

Unused conduit is acoustically filled and capped. An open pipe is an open microphone.

CTTA

Metallic penetrations

Dielectric breaks, grounding and filtering are built exactly as the CTTA’s review and the drawings specify.

Lab 04 Acoustics

How much does the wall let through?

SCIF acoustic protection keeps classified conversations from being overheard outside. The Tech Spec expresses it as Sound Groups tied to a wall’s Sound Transmission Class (STC). Slide the rating and watch what reaches the hallway.

Wall rating

STC 45

Sound Group 3 · 4550 · Sound Group 4

Room use

Discussion unamplifiedVTC / amplified audio

Meets the Sound Group 3 target for a discussion room.

Sound Group 3

STC 45 or better · field: NIC 40

Meets

“Loud speech from within the SCIF can be faintly heard but not understood outside the SCIF. Normal speech is unintelligible with the unaided human ear.”

Default for the SCIF perimeter.

Sound Group 4

STC 50 or better · field: NIC 45

Below

“Very loud sounds within the SCIF, such as loud singing, brass music, or a radio at full volume, can be heard with the human ear faintly or not at all outside the SCIF.”

Conference rooms, VTC and other rooms with amplified audio.

Plain English At STC 45 the wall meets Sound Group 3: loud speech may be faintly heard outside but not understood. It isn’t rated for amplified audio.

The lab number isn’t the field result

STC comes from lab tests (ASTM E90). At accreditation, walls and openings are checked in place, by audio test or instrumented test to NIC 40 (Sound Group 3) or NIC 45 (Sound Group 4) per ASTM E336. The AO decides which.

Buy 5 points of margin

Flanking paths (ducts, door gaps, back boxes, deck flutes, unsealed track) pull field performance below component ratings. UFC 4-010-05 asks for lab-tested assemblies of no less than STC 50 for Sound Group 3 and STC 55 for Sound Group 4.

Rooms change use

A room built to Sound Group 3 that later gets VTC needs Sound Group 4. Some practitioners design every discussion area to Sound Group 4 to avoid a retrofit.

Perimeter & vaults Penetrations & life safety Acoustics & sound masking

06 Intrusion detection & UL 2050

What “Extent 3” actually means.

Most confusion around SCIF alarms comes from mixing up mercantile burglar-alarm certificates with the UL 2050 National Industrial Security Systems program. A SCIF needs the latter.

“Installation shall comply with an Extent 3 installation as referenced in UL 2050.”
IC Tech Spec, paragraph 7.A.2.b

An extent is UL’s designation for the amount of alarm protection installed for an area, room or container.
Extent 3 is the baseline for closed areas and SCIFs; Extent 5 — which 32 CFR 117.15(d)(4)(ii) describes as a level of protection “based on patrolling employees and CSA approval of security-in-depth” — needs prior government approval.
Systems developed and used by the U.S. Government don’t need UL certification, but must still meet the Extent 3 installation requirements.
Full extent definitions live in the licensed UL 681 and UL 2050 texts — ask for the certificate and verify it in UL’s directory.

12 numbers every IDS installer should know

Extent 3UL 2050 installation level
Level IIUL 634 high-security switch on perimeter doors
UL 639Motion sensors — HSS and motion on every perimeter door
≤ 30 sEntry delay at the primary door
24 hUninterruptible backup power
≤ 1 / 30 dFalse alarms per IDS partition
15 minResponse force, closed storage
15 / 5 minOpen storage with / without SID
60 minSCI-indoctrinated person on site (or AO-approved time)
4 hService start after a trouble signal
6 moRecurring (semiannual) IDS test
3 of 4Motion walk-test trials that must alarm

IC Tech Spec Ch. 7 and 3.H. Some items allow an AO-approved alternative — get it in writing.

Lab 05 Alarm response

The clock starts at the alarm

How fast someone must respond depends on how the SCIF stores material and whether Security-in-Depth covers it. Press play to run a scaled simulation of every clock from the same moment.

Simulation speed

1 min = 1 s1 min = 0.1 s

Since alarm 0:00:00

Response force

Closed storage

Response force on site within 15 minutes of the alarm.

Ready

Tech Spec 3.H(a)

Open storage, with Security-in-Depth

Within 15 minutes of alarm annunciation when the area is covered by AO-accepted SID.

Ready

Tech Spec 3.H(b)

Open storage, without SID

A five-minute alarm response when there’s no Security-in-Depth.

Ready

Tech Spec 3.H(b)

Follow-up

SCI-indoctrinated person on site

Arrives within 60 minutes per UL 2050, or the AO-approved time, then inspects, finds the cause and resets the IDS before the response force leaves.

Ready

Tech Spec 7.C.1

Service technician starts repairs

Within 4 hours of a trouble signal or service request. Until it’s fixed, SCI-indoctrinated staff occupy the SCIF around the clock unless the AO approves alternate procedures.

Ready

Tech Spec 7.C.2

An alarm is an intrusion until resolved

The response force protects the SCIF under a written support agreement until SCI-indoctrinated personnel arrive.

SID is documented, not assumed

The 15-minute open-storage clock depends on the AO accepting SID. If that layer changes (lobby access control removed, a new tenant mix, a moved fence line), the SCIF may need a 5-minute response. Take it to the AO.

Continuous operation

Tech Spec 3.H doesn’t state a separate IDS response time for continuous-operation SCIFs. Get the AO’s determination in writing.

Intrusion Detection & UL 2050 module Vetting a UL 2050 alarm company

07 Access control & door hardware

The reader opens the door. The lock secures the SCIF.

Access control manages who enters during duty hours. When the room is empty, the FF-L-2740B combination lock and the armed IDS protect it. Design the door as one stack, not a pile of parts.

Primary entrance stack (public-level concept). Exit-only doors use FF-L-2890 exit hardware with no outside trim and are alarmed 24/7.

01
Two technologies at the door
Automated entry uses at least two technologies; DoD design criteria call for a card reader with keypad at the primary entrance. Readers outside the SCIF are tamper-protected.
02
Head-end inside
ACS head-end in the SCIF or in an alarmed area controlled at the SECRET level; no cloud or building-wide server in unsecured space without AO approval.
03
Encrypt what leaves
Reader and panel lines that leave the SCIF are encrypted (FIPS 140 validated) or protected by an AO-approved method.
04
The lock still locks
ACS is not approved to secure an unoccupied SCIF. When empty: FF-L-2740B lock closed and IDS armed; secondary-door ACS shut off.
05
Fail-secure strikes
Electric strikes are UL 1034, fail-secure, and coordinated with the FF-L-2890 hardware the combination lock mounts on.
06
No cameras inside
Entrance cameras supplement access control only; no cameras inside or viewing into the perimeter, and never aimed at keypads or displays.

Platform spotlight

Hirsch — high-security access control built for federal entrances

Hirsch (Hirsch Group, formerly Vitaprotech; previously part of Identiv) describes itself as a long-time provider of high-security access control to the U.S. federal government, and its Velocity platform is the one we lead with for secure entrances. What the Hirsch datasheets state, and what the public record shows when you check them:

Velocity — specify the APL build

Hirsch's security management software — from single high-secure rooms to multi-building campuses; Alarm Viewer and Who's Inside views; PIV/CAC/TWIC validation via VCCS. Hirsch ships 3.9, but GSA APL #10103 approves Velocity 3.8.6 with VCCS 3.8.5, CCM/CCMx 8.3.00.73 and SNIB3 4.02.1554 — and Hirsch's own 3.9 release notes point federal customers to that same stack. An APL update is in GSA's test queue. Specify the APL build on federal work, and confirm the build and part numbers at quote.

Mx controllers

UL 294 and UL 1076 listed; two-person rule, occupancy counting, door interlocking, anti-passback. On cryptography, ask for a certificate number: the Mx datasheet claims FIPS 140-3 with TLS v1.3, other current Hirsch datasheets describe the same SNIB3 as FIPS 140-2, and NIST's CMVP list shows no validated module for Hirsch or Identiv.

Alarm line modules

High-security line supervision and alarm masking; supervision measured 100 times per second; SBMS-L2HSS contact meets UL 634 Level 2.

TS ScramblePad

Keypad digits re-scramble on every use with viewing restrictors — protects the PIN that SCIF entrances depend on. UL 294; GSA APL per Hirsch.

Manufacturer claims, not accreditation approvals. No product is “ICD 705 certified.” Final system design, IDS/ACS integration and door hardware are subject to approval by the Accrediting Official / Cognizant Security Authority, and the CTTA where TEMPEST applies. Read the full Hirsch sections.

08 RED/BLACK, EMI filters & shield penetrations

Signals leak along anything that conducts.

Many SCIFs are not RF-shielded — shielding and other TEMPEST countermeasures are required only when the Certified TEMPEST Technical Authority (CTTA) says so. But any project that processes classified information needs RED/BLACK discipline, and every installer needs to understand how a penetration is made without creating a leak.

RED

Unencrypted classified

Equipment, wiring and signals that carry classified information in the clear. Controlled by the CTTA’s countermeasures — separation, filtering, fiber and inspectable space.

BLACK

Encrypted or unclassified

Signals that are encrypted or never classified — the unclassified LAN, building systems, telephones. Kept from coupling with RED.

Why no distances here? Current RED/BLACK installation guidance (CNSSAM TEMPEST/1-13) is a controlled document. Separation and treatment for any facility are set by its CTTA — this site teaches the concepts, never the numbers.

Lab 06 Penetrations & filters

Short answer: at the penetration, and either face. MIL-HDBK-1195 §2.8 puts filters “at the conductor penetration locations, either inside or out, depending usually on available access or space.” Nothing in that section prefers one face over the other for a filter mounted at the penetration. What is not a free choice is everything else. Any wire crossing an RF shield carries RF straight through it, so the filter only works if its case is bonded into the shield and the unfiltered conductors stop there: dirty conductors terminate on the unprotected side, and only filtered conductors carry on into the room. That part is a rule about conductors, not boxes. Both faces are drawn below — switch between them and watch what does and does not change. A filter that cannot sit at the penetration is a different case with its own rules — see “If it can’t go at the penetration” below.

Lab 07 RF physics

Waveguide-beyond-cutoff calculator

A bonded metal tube passes air, water or fiber, yet RF well below the tube’s cutoff frequency dies away exponentially along its length. The opening size sets the cutoff; the length sets how much attenuation you get below it.

Educational estimate — your CTTA/shielding engineer sets requirements. This is ideal-tube theory; the shield vendor’s tested design governs.

Cutoff frequency f_c: 6.92 GHz; Below this, the tube won’t propagate
Attenuation at f: 158 dB; Theoretical, ideal tube
Low-frequency limit: 160 dB; When f ≪ f_c
Length ratio L/D: 5.0; ≈ 32 dB per diameter (circular)

Theoretical attenuation vs frequency Log frequency axis

below cutoff: attenuatesat or above cutoff: propagatesfrequency of concern

Show the math

Circular, TE₁₁ f_c = 1.841·c / (π·D) = c / (1.706·D)

Rectangular, TE₁₀ f_c = c / (2·a) a = widest inside dimension

Filled with a dielectric f_c ÷ √ε_r water, ε_r ≈ 80 → about 9× lower

Attenuation below cutoff α = (2π/λ_c)·√(1 − (f/f_c)²) Np per unit length; A = 8.686·α·L dB

For f ≪ f_c A ≈ 32 × L/D (circular) · A ≈ 27.3 × L/a (rectangular)

Never put a conductor through a waveguide

A wire, metallic cable or fiber with a steel strength member turns the tube into a coaxial line. A coax has no cutoff, so this math stops applying.

Theory vs. the real thing

Real limits come from the weld or bond, not the math. Measured honeycomb panels come in far lower than ideal-cell theory: Tech-Etch reports 40–75 dB for ⅛″ cells ½″ deep (chem film), 60–105 dB cross-cell, 100 kHz–10 GHz.

Water is simplified here

The water setting treats ε_r as a constant 80 and ignores the water’s own losses. Sprinkler and water waveguides must be engineered for the fluid.

Presets Pipe and conduit sizes are nominal; use the measured inside diameter. Hexagonal cells are modeled as circles of the cell size. Preset lengths are example geometry, not requirements.

For installers

Never fasten through the shield.

A single drywall screw through foil or steel shielding is a hidden leak. Mounting a door contact above a shielded door, running cable to a device or hanging a raceway all have a method that leaves the shield intact.

Z- or L-bracket
Mount the high-security switch to the door frame or header on the protected side with the switch maker’s bracket and spacers — never field-drill a shielded frame for a concealed switch.
Strut standoff
Unistrut-type standoffs fastened where the shield designer allows keep device weight off the shield.
Furred chase
A furred or secondary stud wall inside the shield becomes the device and cable chase; fasteners go into the furring, not the shield.
Surface raceway
Route surface conduit or raceway to the penetration panel. Build each penetration exactly as the shield designer details it.
Made a hole?
Stop. Report it. The shielding vendor repairs it and the enclosure is retested as the vendor and CTTA direct — any later penetration means review, then retest.

RED/BLACK, TEMPEST & EMI filters RF shielding & installer methods

09 PEDs, wireless detection & telecom

The vestibule is detection’s best chance.

A vestibule gives detection its best chance: a known person, a closed space and a few seconds of dwell before the inner door opens. Detection feeds the access control interlock — and egress is never blocked.

1
Lockers outside
Devices stored in lockers outside the primary entrance; signage lists prohibited items.
2
Outer door
Credential grants entry; the interlock keeps the inner door locked while the outer door is open.
3
Dwell & detect
RF detector evaluates the zone; optional ferrous or metal screening.
4
Clean or detected
Clean: inner reader enabled — card plus PIN still required. Detected: inner grant inhibited, local alert, event to the SCI-indoctrinated monitor.
5
Inside
Sensor network (if fielded) keeps listening; approved medical devices per AO approval.

What RF detection can’t see

Powered-off devices emit nothing.
Airplane mode can still leave Wi-Fi and Bluetooth on.
Randomized addresses make MAC allow-lists unreliable.
The honest claim is “detects transmitting devices.”

Telephones & speakers

Unclassified phones: TSG-6 (CNSSI 5006) approved instruments or disconnect devices.
Phone systems: TSG-2 (CNSSI 5002); VoIP: CNSSI 5000.
Paging and notification speakers: no audio back-feed.

Cameras

Entrance cameras supplement access control only.
No cameras inside or looking into the perimeter.
Never capture keypads, PINs or displays.

PEDs, wireless detection, telecom & CCTV

10 History

More than eighty years of keeping signals in the room.

From a wartime cipher machine that leaked plain text to today’s ICD 705 Tech Spec. Older documents are listed so you can recognize legacy citations — not so anyone designs to them.

WWII
Bell 131-B2
The Bell Telephone 131-B2 cipher mixer is found to leak plain text as electrical spikes — the problem later code-named TEMPEST.
1951
CIA rediscovery
Plain text recovered "about a quarter mile down the signal line."
30 Oct 1964
NSA 65-6
Early NSA shielded-enclosure specification.
15 Nov 1972
NSA 73-2A
NSA specification later listed as superseded on the undated NSA 89-02 draft shielded-enclosure specification.
1 Feb 1982
NACSIM 5000
"TEMPEST Fundamentals" defines RED and BLACK.
1985
van Eck
Public paper on video-display eavesdropping brings emanations into open research.
24 Oct 1994
NSA 94-106
"Specification for Shielded Enclosures" — released on FOIA appeal in December 2000. Historical.
12 Dec 1995
NSTISSAM TEMPEST/2-95
"RED/BLACK Installation Guidance." Historical \u2014 superseded, with its Feb 2000 addendum, by CNSSAM TEMPEST/1-13 (17 Jan 2014).
May 2004
CNSSI 7000
TEMPEST Countermeasures for Facilities (successor to NSTISSI 7000). Not public.
26 May 2010
ICD 705
Signed; rescinds DCID 6/9 and restructures IC facility standards.
17 Jan 2014
CNSSAM TEMPEST/1-13
Current RED/BLACK installation guidance (date per public listings) — controlled; your CTTA applies it.
26 Jul 2021
Tech Spec v1.5.1
Current published IC Technical Specifications for SCIF construction.
17 Jan 2025
DoDM 5205.07
Consolidated SAP Security Manual; Volume 3 (physical security) cancelled.
7 Apr 2025
UL 2050 Edition 6
Current edition of the National Industrial Security Systems standard.

History of TEMPEST & shielding specs

11 Inspection killers

Twelve mistakes that stop accreditation.

Tap a card to see the fix. The full list — 25 killers plus traps by system — is in the knowledge base.

All traps & common failures Playbooks: real-world scenarios

12 Free downloads

Take it to the project meeting.

Public-level primers, a field guide for GCs and installers, an editable readiness questionnaire and a briefing deck. No sign-up.

Educational material. Do not add classified information, CUI or facility addresses to these documents, and share completed questionnaires only through channels your security officer approves.

Technician training portal

The design-level curriculum lives behind the login.

LA CCTV Supply technicians and authorized project staff sign in with their existing CRM credentials for requirement-by-requirement design training, submittal workbooks and knowledge checks.

Sign in to the portal Authorized personnel only.

Design requirements by system
Chapter-by-chapter Tech Spec requirements mapped to IDS, ACS, CCTV, cabling and door hardware submittals.
Submittal & FFC workbook
How the integrator's drawings, battery calculations and test records feed the Fixed Facility Checklist.
RED/BLACK design lab
Applying CTTA countermeasures in cable plant, power and equipment layouts.
Shielded-space installation
Mounting, routing and hold-point procedures with photo checklists.
UL 2050 commissioning
Acceptance testing, walk tests, records and certificate coordination.
Knowledge checks
Scenario quizzes with per-answer explanations and sources.

FAQ

Quick answers.

Short versions. Each links into the knowledge base for the cited detail.

Open SCIF Answers

What is a SCIF?

A Sensitive Compartmented Information Facility is an accredited area where Sensitive Compartmented Information (SCI) is stored, used, discussed or processed. It is a combination of construction, security systems and procedures that an Accrediting Official has accredited against ICD 705 and the IC Technical Specifications — not a product you can buy.

What is the difference between a SCIF and a SAPF?

A SCIF protects SCI and is accredited under ICD 705 by an Intelligence Community element's Accrediting Official. A SAPF protects Special Access Program information and is accredited by a SAPF Accrediting Official under DoDM 5205.07 (consolidated 17 January 2025), using construction criteria equivalent to the IC Tech Spec. Using one for the other's information requires a co-use agreement.

What does "UL 2050 Extent 3" mean?

The IC Tech Spec (7.A.2.b) requires the intrusion detection installation to "comply with an Extent 3 installation as referenced in UL 2050." An extent describes how much alarm protection is installed for an area; UL's form allows Extent 3 for closed areas, and Extent 5 only with prior government approval. The full extent definitions are in the licensed UL standards.

How fast must a response force arrive after a SCIF alarm?

Inside the U.S., within 15 minutes for closed storage. For open storage, 15 minutes when AO-accepted Security-in-Depth exists and 5 minutes without it (Tech Spec 3.H). Overseas SCIFs and continuous-operation SCIFs have different or AO-set times, so confirm with your AO.

Does every SCIF need RF shielding?

No. Shielding and other TEMPEST countermeasures are required only when the Certified TEMPEST Technical Authority (CTTA) determines they are needed after a TEMPEST countermeasure review. SCIFs that process classified information still need RED/BLACK installation discipline.

Which side of the shield does an EMI filter go on?

At the penetration, and either face. MIL-HDBK-1195 §2.8 puts filters “at the conductor penetration locations, either inside or out, depending usually on available access or space,” with no TEMPEST preference between the two faces. What is not a free choice is the conductors and the bond: the case is bonded metal-to-metal into the shield plane so it closes the hole it occupies; the unfiltered LINE conductors terminate on the unprotected side and never cross, and only the filtered LOAD conductors continue into the room. So it is a rule about conductors, not boxes. The sentences that follow in §2.8 open a different case — a filter mounted remotely from the shield — and it is that case that requires continuous metal conduit, puts TEMPEST conduit runs inside the enclosure, and requires a controlled access area when the remote filter sits outside. The clean-side penetration detail follows the project specification — welded pipe on most government work, a compressed RF gasket on many commercial rooms. And all of this is the shielded-enclosure case: at a non-shielded SCIF perimeter there is no shield plane to bond into, and the grounding and bonding detail comes from the CTTA, the engineer of record and the drawings.

Can access control secure an empty SCIF?

No. When the SCIF is unoccupied it is secured by the FF-L-2740B combination lock and the armed intrusion detection system. Access control manages entry during duty hours, and access control on secondary doors is shut off when the SCIF is empty.

Is there such a thing as an "ICD 705 certified" product?

No. Products may carry listings such as UL 294, UL 634 or UL 639, or appear on the GSA FIPS 201 APL, but the facility is what gets accredited — by the AO, against the approved design.

A SCIF is a result, not a product.

Physical

Technical

Procedural

Four ways classified information is protected

Walk through a SCIF suite, one requirement at a time.

Detection starts long before the SCIF wall.

Paper first. Then drywall.

Deliverables

Who produces

Who approves

Integrator / GC tasks

Typical traps

Deliverables

Who produces

Who approves

Integrator / GC tasks

Typical traps

Deliverables

Who produces

Who approves

Integrator / GC tasks

Typical traps

Deliverables

Who produces

Who approves

Integrator / GC tasks

Typical traps

Deliverables

Who produces

Who approves

Integrator / GC tasks

Typical traps

Deliverables

Who produces

Who approves

Integrator / GC tasks

Typical traps

True floor to true ceiling — and nothing sneaks through.

Ducts & vents

Single point of utility entry

Spare conduit

Metallic penetrations

What “Extent 3” actually means.

12 numbers every IDS installer should know

Closed storage

Open storage, with Security-in-Depth

Open storage, without SID

SCI-indoctrinated person on site

Service technician starts repairs

The reader opens the door. The lock secures the SCIF.

Two technologies at the door

Head-end inside

Encrypt what leaves

The lock still locks

Fail-secure strikes

No cameras inside

Hirsch — high-security access control built for federal entrances

Velocity — specify the APL build

Mx controllers

Alarm line modules

TS ScramblePad

Signals leak along anything that conducts.

Unencrypted classified

Encrypted or unclassified

Never fasten through the shield.

Z- or L-bracket

Strut standoff

Furred chase

Surface raceway

Made a hole?

The vestibule is detection’s best chance.

Lockers outside

Outer door

Dwell & detect

Clean or detected

Inside

What RF detection can’t see

Telephones & speakers

Cameras