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Premier Security Ballistic & Blast Ltd
Attack, Blast and Gas Protection
Premier Security Ballistic & Blast Ltd provides gas tight and air tight doorsets, blast valves for protected ventilation, and attack resistant doorsets that can incorporate radio frequency and acoustic attenuation, for facilities where a single opening has to hold against more than one threat.
Most protected facilities are specified one threat at a time. The security consultant writes the forced entry requirement, the blast engineer writes the overpressure requirement, the mechanical engineer writes the containment and ventilation requirement, and the shielding specialist writes the attenuation requirement. Each is competent in isolation, and each stops at the face of the opening.
The openings are where those requirements collide. A door that satisfies four separate specifications is not four doors, and the interfaces between the requirements are exactly where performance is lost. This part of our offering exists to resolve them as one problem.
Gas Tight and Air Tight Doors
Gas tight and air tight doorsets provide sealed access where an environment must be held at a differential pressure, or where the migration of gas, vapour or airborne contamination between spaces must be prevented.
They are found in bio-hazard laboratories, nuclear and blast protected bunkers, water treatment facilities, hospitals, military buildings, universities and research establishments. In each case the door is protecting against a specific identified hazard, which may be radioactive, bio-hazardous or an industrial by-product, and the doorset is designed and specified to that requirement rather than selected from a catalogue.
Seal Selection
Seal material is the primary specification decision and is driven by what the seal has to resist and how often it is compressed.
| Material | Typical application |
|---|---|
| Neoprene | Frequently used air lock chambers, where the seal is cycled repeatedly and recovery matters more than chemical resistance |
| EPDM rubber | Environments requiring a seal against toxic chemicals, where chemical compatibility governs |
Locking and Access Control
Locking options range from conventional key operation through to specialist electro-mechanical access with auto deadlocking and electronic monitoring. On a gas tight doorset the locking system is not only a security decision: it determines the compressive force applied to the seal and therefore the leakage performance achieved, which is why it should be settled alongside the seal rather than after it.
Pressure Testing
Air permeability of a gas tight doorset is a measured property. Doors are mounted to a test chamber and pressurised continuously for one hour, then isolated from the pumping system and left connected to an airflow meter for a further hour to measure leakage, under both positive and negative pressure. Full details are on our testing and support page.
A gas tight door that has never been pressure tested is a gas tight door in name only. Leakage is the specification; everything else is the means of achieving it.
Blast Valves
A protected envelope still has to breathe. Where a facility requires substantial airflow but cannot accept an unprotected opening, blast valves provide ventilation that closes automatically under blast loading.
The valve is held open in normal operation. On the arrival of a blast wave it closes on impact, remains closed through the reverse pressure phase that follows, and returns to its open position once the event has passed. That second stage matters: the negative phase of a blast event is frequently what defeats protection designed only for the initial positive overpressure.
Valves are supplied as modules fitted into wall frames and can be installed vertically or horizontally, suiting both inlet and exhaust air. We provide pre-engineered units and tailor-made configurations, and because these projects are rarely standard, configurations can be developed around the specific airflow, opening geometry and threat level required. Valves can additionally be configured to provide electromagnetic pulse protection and debris protection within the same unit, which avoids stacking separate devices in a single duct run.
2 pressure phases. A blast event pushes and then pulls. Protection that only addresses the first is protection that fails on the second.
Attack Resistant Doors with RF Shielding
Some openings have to keep people out and signals in. A secure communications room, a government meeting space or a protected server hall may need a doorset that resists a determined forced entry attempt while also forming part of a continuous electromagnetic envelope, and often while attenuating speech as well.
We provide attack resistant doorsets that can incorporate radio frequency attenuation and acoustic performance alongside certified forced entry resistance. Locking is available in single and multi-point configurations, doors can be supplied inward or outward opening and in any colour, and optional extras include weather seals, cylinder guards and observation apertures. Most access control systems can be integrated, and electrically operated versions are fail secure.
Certified performance levels, tested locking configurations and permitted dimensional ranges are confirmed against the specific product selected at specification stage, and installation is carried out so that the certified rating is maintained.
Combined Performance Requires Combined Evidence
This is the most important principle on the page, and the one most often misunderstood in procurement.
Forced entry resistance, blast performance, fire resistance, gas tightness, radio frequency attenuation and acoustic attenuation are six separate properties. Each is verified under its own standard, by its own test method, against its own pass criteria. A doorset can be designed and tested to deliver several of them at once, and we regularly supply doors that do, but no one of them can be inferred from another.
- A door with a certified security rating is not thereby fire rated
- A fire rated door is not thereby gas tight
- A gas tight door is not thereby blast resistant
- An RF shielded door is not thereby attack resistant
- A door tested in one configuration is certified in that configuration, not in every variant of it
Where a doorset carries multiple performance claims, each should be supported by its own test evidence, and that evidence should name the tested product and the certifying body. We would encourage any specifier to ask for it explicitly, from any supplier, including us.
Premier Security's Certified Physical Protection
Alongside the shielding division, Premier Security supplies independently certified high security architectural products developed over more than 30 years.
- Forced entry resistance to LPS 1175, across SR2/B3, SR3/C5, SR4/D10 and SR5/E10, certified by LPCB
- Blast resistance to ISO 16933, with curtain walling certified up to EXV25
- Bullet resistance to EN 1522/1523 for complete assemblies, from FB2 to FB7, and EN 1063 for glazing, from BR2 to BR7, each with the applicable S or NS spall classification
- Fire performance to LPS 1056
- Hostile vehicle mitigation to ISO 22343-1:2023
Where a project requires certified physical protection alongside shielding or containment, those requirements are met through these ranges and coordinated with the shielding envelope from the outset rather than reconciled on site.
Sectors We Support
- Bio-hazard and containment laboratories
- Nuclear facilities and protected bunkers
- Defence establishments and military buildings
- Government estates and secure communications facilities
- Water treatment and critical national infrastructure
- Hospitals and healthcare estates
- Universities and research establishments
- Data centres and government and defence-adjacent compute facilities
Attack, Blast and Gas Protection FAQs
What is the difference between a gas tight door and an air tight door?
In practice the terms are used interchangeably, and both describe a doorset designed to limit air or gas migration across the opening to a measured leakage rate. The meaningful distinction is not the label but the specification: the differential pressure the door must hold, the substance the seal must resist, and the leakage rate that must be demonstrated by test.
Does a blast valve replace a blast door?
No. They address different openings. A blast door protects an access opening used by people. A blast valve protects a ventilation opening that must remain open in normal operation to allow airflow. A protected envelope typically needs both, along with treatment for every other penetration through the boundary.
Can one doorset provide security, blast, fire and RF performance together?
Yes, doorsets can be designed to deliver multiple performances, and combined requirement doors are common in defence and government projects. What cannot happen is inference between them. Each performance must be evidenced by its own test against its own standard, and a claim for one is never a claim for another. Ask for the test evidence behind each performance separately.
How is gas tightness verified?
By pressure testing. The doorset is mounted to a test chamber and held at a controlled test pressure for one hour, then isolated and monitored on an airflow meter for a further hour to measure leakage, under both positive and negative pressure. Testing is generally performed to the relevant European air permeability test method for windows and doors, or to customer specific requirements where a project demands it.
At what stage should these requirements be set?
Before the door schedule is issued, and ideally at RIBA Stage 2 or 3. Combined performance doorsets have longer lead times, larger structural openings and different frame fixing requirements than standard doors. Introducing a combined requirement after the openings are set almost always means either a compromised specification or a change to the structure.