LPS 1175 D10 (SR4) Security Rating: Certified Curtain Walling, Doorsets and Gates

LPS 1175 D10, the Issue 8 rating commonly compared with SR4, certifies that a complete product has resisted an experienced attacker with a professional cordless toolkit, including 18V disc grinders and reciprocating saws, for at least ten minutes. It is widely specified for data centres, utilities, high-value commercial sites and embassies. Premier Security Ballistic & Blast Ltd manufactures LPCB certified D10 curtain walling doorsets, screens and fixed windows, Ultimate High Security Curtain Walling 4 and Kraken 4 sliding gates, all listed on LPCB Red Book Live.

What Does LPS 1175 D10 Mean?

LPS 1175 is the Loss Prevention Standard for intruder resistant building components, published by the Loss Prevention Certification Board (LPCB), part of BRE Global. Every Issue 8 rating has two parts: the letter sets the tools the attacker can use, and the number sets the minimum delay in minutes the product must achieve.

At D10, the test team attacks the locked product with Category D tools and must not create a 400 mm x 225 mm opening, the minimum size a person can climb through, within ten minutes of working time. Any part of the assembly can be targeted, including the leaf, frame, glazing, infill panels, hinges, locks and fixings.

The Category D tool set

Category D is the point where power tools enter the test. It represents an experienced criminal with a professional cordless toolkit, prepared to make noise and work for a sustained period. The kit includes everything in Categories A to C plus:

• Categories A to C: hand tools, bolt cutters, a claw hammer, a cordless drill, an axe, a crowbar, a lump hammer, cold chisels and a gas torch
• Added at Category D: 18V cordless disc grinders, reciprocating saws, jigsaws, circular saws and sledgehammers

Power tools change the nature of the attack. A cordless disc grinder or reciprocating saw can cut through steel sections, bolts and locks that hand tools would struggle with, so a D10 product has to resist cutting as well as leverage and impact, and do it for twice as long as a C5 product.

D10 vs SR4: Issue 8 and Issue 7 Explained

LPS 1175 Issue 8 came into effect in 2019 and was the most substantial revision of the standard to date. It replaced the single SR1 to SR8 scale with a tool category letter (A to H) followed by a minimum delay in minutes (1, 3, 5, 10, 15 or 20). D10 is the Issue 8 classification commonly compared with the old SR4: an experienced attack with Category D tools, held off for at least ten minutes.

All of Premier Security's D10 products are certified under Issue 8, so their certificates show D10 and the products can be described as D10 (SR4) for comparison with older specifications.

Premier Security's D10 Certified Products

Premier Security holds LPCB certification for the following products at D10. Sizes are the certified structural openings shown on each certificate. Openings outside these ranges are not covered by the rating, so our technical team will confirm the certified configuration for every opening.

Where D10 Is Specified

D10 suits sites where the credible threat is an experienced attacker with power tools, or where the assets or operations inside justify a ten-minute delay. Typical applications include:

• Data centres
• Utilities and energy sites
• High-value commercial premises
• Industrial and logistics facilities
• Embassies and government buildings
• Military and defence sites

The right rating comes from a security risk assessment that weighs the asset value, the likely capability of an attacker and the time a response needs to arrive. In high-risk and critical infrastructure contexts, that assessment is typically informed by NPSA (National Protective Security Authority) guidance. Our technical team can review the assessment and recommend a rating for each opening.

Specifying a D10 Product: Checklist

• Confirm the certificate shows D10 under Issue 8 (both the letter and the number) and check the listing on Red Book Live
• Check the opening size falls within the certified structural opening, and note that the Jansen Façade D10 doorset is certified outward opening only
• Use only the locking systems listed on the certificate, including the minimum number of maglocks and the extra maglocks needed on leaves over 3 m
• Confirm the glazing and infill panels are within the certified options for that product
• Detail the fixings and substrate, as the frame to structure connection sits outside the certificate
• For screens and curtain walling, design the structural performance separately, as it is outside the scope of LPS 1175
• For Kraken 4 gates, allow for the 2.8 m minimum free-standing height and specify access control with at least 30,000 effective codes
• For maglocked doorsets and gates, plan an uninterrupted power supply if the rating must hold during a mains failure
• Remember that resistance of access control systems to non-mechanical attack is outside the scope of LPS 1175

Frequently Asked Questions: LPS 1175 D10 and SR4

Related Premier Security Resources

• LPS 1175 Security Ratings Explained: the full SR1 to SR8 and A1 to H20 guide
• LPS 1175 C5 / SR3 Rating Guide: the rating below D10, for commercial premises, schools and retail
• LPS 1175 SR2 / B3 Rating Guide: for communal and low-risk openings
• LPS 1175 for Data Centres: certified doors and windows for data centre security
• Security Curtain Walling: Ultimate High Security Curtain Walling from C5 to E10
• Jansen Security Doors: steel framed glazed door systems
• Vehicle Access Sliding Gates: certified cantilever sliding gates
• Contact Premier Security: technical consultation and project enquiries