Forced entry resistant glazing — buying time, not invulnerability.
ASTM F1233 and the newer ASTM F3561 systems standard, UFGS 08 34 01, and what "forced entry resistant" actually means when the drawings call for it. Written for Florida school, courthouse, and federal work.
ASTM F1233 — the security glazing test.
ASTM F1233 is the Standard Test Method for Security Glazing Materials and Systems — it tests forced-entry resistance, not just ballistic performance, though ballistic attack is one of several attack sequences it covers. A test lab subjects a glazing sample to defined attack sequences — including blunt and sharp tool attack, repeated impact, and in some classes ballistic fire followed by tool attack — for a specified time window. The assembly passes a given classification if it isn't breached within that window.
That's the key conceptual shift from a ballistic-only spec: F1233 measures delay time, not a pass/fail stopping event. The classification system includes multiple grades tied to different attack combinations and durations, similar in structure to UL 752's tiered levels but testing a different failure mode — sustained physical breach attempts rather than a single projectile event.
ASTM F3561 — testing the "shoot-then-smash" pattern.
ASTM F3561 is a newer (2021+) standard written specifically to address an attack pattern documented in active-shooter incidents: an attacker shoots the glazing to weaken it, then physically smashes through to reach a door handle or force entry. F1233 tests glazing materials against defined attack sequences; F3561 goes a step further and tests the entire installed system — glass, frame, fasteners, and anchoring — together, exactly as it would be built.
The F3561 test sequence: the assembly is first subjected to a defined shot grouping, then struck with a 100-pound pendulum impactor dropped from increasing heights until breach or a defined performance threshold. Because it tests glass, frame, and anchorage as one unit, F3561 results don't transfer if any part of the installed system changes from what was tested — the same system-dependency issue that runs through every ballistic and forced-entry standard on this site.
F3561 is increasingly referenced in school security and active-shooter mitigation specs, precisely because it targets that specific attack sequence rather than a generic ballistic or forced-entry threat in isolation.
UFGS 08 34 01 — Forced Entry Resistant Components.
UFGS 08 34 01 is the DoD Unified Facilities Guide Specification for Forced Entry Resistant Components — one of the boilerplate spec sections primes and subs actually bid against on federal work, hosted on the Whole Building Design Guide (WBDG). It's the federal-project counterpart to a commercial architect writing a security-glazing spec section: it references the applicable ASTM test methods, sets submittal and testing documentation requirements, and defines the acceptance criteria a delivered assembly has to meet.
Seeing UFGS 08 34 01 called out on a federal Div 08 spec means the reviewing agency wants a tested, documented forced-entry assembly — not a field-built approximation. The submittal chain looks similar to AT/FP blast work: sealed test data for the specific assembly configuration, a mock-up where required, and field QC documentation tying the installed product back to the tested one.
The references you'll see on a forced-entry Div 08 spec.
Forced-entry glazing buys time. It does not make an opening invulnerable.
Every forced-entry classification under F1233 and F3561 is expressed in terms of time and attack sequence, not an absolute barrier claim. A given classification means the tested assembly resisted a defined attack for a defined duration — long enough, in the design intent, for a lockdown to take effect, for law enforcement to respond, or for occupants to evacuate or shelter. It does not mean the opening cannot eventually be breached with enough time, force, or the wrong tool.
This matters for how the assembly gets specified and how ACG talks about it with owners: forced-entry glazing is one layer in a broader security design — door hardware, lockdown procedure, sightlines, response time — not a standalone guarantee. Selling it as anything more than a delay mechanism sets an unrealistic expectation the glazing was never tested to meet.
Where forced-entry glazing shows up.
- Schools — main-entry vestibules and classroom-door sidelites are the most common application. School security hardening is an active area of interest for Florida districts; ACG prices to whatever forced-entry classification and testing standard (F1233, F3561, or both) is called out in the project-specific spec. We don't make claims about what any particular Florida statute mandates — that's a district-and-engineer determination, and the controlling requirement is always the project spec, not a general assumption about school security law.
- Courthouses — public entrances, security screening vestibules, and holding-area glazing.
- Federal facilities — per UFGS 08 34 01 on DoD projects, and comparable agency-specific spec sections elsewhere in federal work.
- Pharmacies — narcotics storage areas and after-hours service points, often combined with a UL 752 ballistic rating at the same opening.
Retrofit is a different scope than new construction.
New-construction forced-entry glazing gets designed into the opening from the start — frame, anchorage, and glazing selected together against the spec'd classification. Retrofit work (adding forced-entry glazing to an existing school or public building) has a different set of constraints: the existing frame and wall assembly weren't necessarily built to carry a heavier, tested forced-entry system, and F3561-type systems ratings depend on the frame and anchoring being part of the tested configuration. Retrofitting the glass alone into an untested existing frame does not carry the rating forward — this has to be evaluated opening by opening, not assumed.
Common Div 08 spec traps on forced-entry scopes.
Glass swapped into an untested frame
F1233 and especially F3561 rate a tested system, not a glass makeup. Retrofitting rated glass into an existing, untested frame doesn't transfer the classification — flag this before pricing a retrofit.
F1233 classification cited without the attack type
F1233 has multiple classification grades tied to different attack sequences (tool, ballistic, combination). "F1233-rated" alone doesn't specify which — confirm the exact classification and attack type before bid.
F1233 vs. F3561 confusion
Some specs reference F1233 when the actual design intent is the shoot-then-smash scenario F3561 addresses. Worth raising with the design team if the use case (e.g., active-shooter mitigation) points to F3561.
Door hardware not upgraded with the glazing
A forced-entry rated lite in a door with standard hinges and a standard strike defeats the point — hardware has to match the assembly's rated resistance, not just the glass.
No statutory claims assumed
We price to the spec in front of us. We don't represent that a given assembly satisfies any specific state school-security statute — that determination belongs to the district's engineer of record.
What we do about it
We flag each of these in writing at the RFI stage on any forced-entry scope we price — before we quote, not after award.
Essential-facility experience, stated plainly.
ACG prices forced-entry resistant glazing scopes to project-specified references — F1233, F3561, or UFGS 08 34 01 on federal work — as a Division 08 subcontractor, coordinating glass, frame, and anchorage as the single tested system the classification depends on. Our verified public-sector past performance is essential-facility work — the Haines City Public Safety Complex & EOC (25,443 SF, GC Pirtle Construction, completed 2025), the Cudjoe Key fire station for Monroe County, and the Martin County Fire Training facility. Laminated impact assemblies, Risk Category IV design pressures, and the documentation chain that comes with institutional owners.
Forced-entry glazing questions specifiers ask.
What is ASTM F1233?
ASTM F1233 is the Standard Test Method for Security Glazing Materials and Systems. It tests forced-entry resistance by subjecting a glazing sample to defined attack sequences — tool attack, repeated impact, and in some classifications ballistic fire followed by tool attack — for a specified time window. The assembly passes a given classification if it isn't breached within that window; the result is expressed as a delay time, not a simple pass/fail stopping event.
What is ASTM F3561 and how is it different from F1233?
ASTM F3561 is a newer systems-level standard that tests glazing, frame, fasteners, and anchoring together, exactly as installed, against a "shoot-then-smash" attack: a defined shot grouping followed by a 100-pound pendulum impactor dropped from increasing heights. F1233 tests glazing materials against forced-entry attack sequences; F3561 specifically targets the active-shooter tactic of weakening glass with gunfire, then physically breaching it.
What is UFGS 08 34 01?
UFGS 08 34 01 is the DoD Unified Facilities Guide Specification for Forced Entry Resistant Components, hosted on the Whole Building Design Guide (WBDG). It's the federal boilerplate spec section referencing ASTM test methods and defining submittal, testing, and acceptance requirements for forced-entry glazing scopes on DoD construction.
Does forced-entry glazing make an opening impenetrable?
No, and no test standard claims that. Every F1233 and F3561 classification is a delay-time rating — the assembly resisted a defined attack sequence for a defined duration in testing. It buys time for lockdown, response, or evacuation; it does not mean the opening can never be breached given enough time, force, or the wrong tool. Forced-entry glazing is one layer in a broader security design, not a standalone guarantee.
Can existing school windows be retrofitted with forced-entry glazing?
Sometimes, but the rating depends on the whole system — glass, frame, and anchorage — not the glass alone, especially under F3561. Retrofitting rated glass into an existing, untested frame does not automatically carry the classification forward. Each opening needs evaluation by the engineer of record to confirm the existing frame and wall can support a tested forced-entry configuration, or whether frame replacement is required.
Does ACG price forced-entry resistant glazing scopes?
Yes. ACG prices and installs forced-entry resistant glazing systems to project-specified references — ASTM F1233, ASTM F3561, or UFGS 08 34 01 on federal work — as a Division 08 subcontractor. ACG's verified public-sector past performance is essential-facility work — the Haines City Public Safety Complex & EOC, the Cudjoe Key fire station (Monroe County), and the Martin County Fire Training facility. FL CGC #1531993.
Related pages
Sending a forced-entry glazing scope to bid?
Send Division 08 to [email protected]. We read it against the specified F1233 / F3561 classification, check frame and anchorage against the tested configuration, and surface any bid-stage risks in writing before we quote.