Marine Exposure Class Mix Design, Volume & Cost Estimator – Updated 2026 Prices
XS2 is the BS EN 206 / BS 8500 exposure class for concrete permanently submerged in seawater — subject to chloride attack without freeze-thaw cycling. Enter your element dimensions and project details to calculate the required concrete volume, BS 8500-compliant mix specification, material quantities, cover requirements, and estimated cost. Always confirm the final mix design with a concrete technologist and the structural engineer.
XS2 is one of the marine chloride exposure classes defined in BS EN 206:2013+A2:2021 (Concrete — Specification, Performance, Production and Conformity) and its complementary British Standard BS 8500-1:2015+A2:2019. The XS series covers concrete exposed to chlorides from seawater, recognising that chloride attack is the principal durability threat to reinforced concrete in marine environments. XS2 specifically describes concrete that is permanently submerged in seawater — below the lowest astronomical tide level — where the concrete is continuously saturated with chloride-laden water but is not subject to the additional mechanical and freeze-thaw stresses present in the tidal and splash zones.
The three marine chloride exposure classes under BS EN 206 are: XS1 (exposed to airborne salt but not direct contact with seawater — coastal structures within approximately 1km of the coast); XS2 (permanently submerged — foundations, piles, jetty understructure, culverts); and XS3 (tidal, splash, and spray zones — the most aggressive marine chloride environment, combining chloride ingress with cyclical wetting and drying, and in some locations freeze-thaw action). XS2 is considered less aggressive than XS3 because the permanently saturated condition, while promoting chloride diffusion, prevents the cyclical drying that accelerates chloride transport in XS3 exposures. However, XS2 remains a demanding durability environment requiring a carefully specified, high-quality concrete mix.
The critical durability mechanism in XS2 exposure is chloride-induced corrosion of reinforcement. Seawater contains approximately 19,000–20,000 mg/litre of chloride ions. These ions diffuse through the concrete cover, and once the chloride concentration at the reinforcement surface exceeds the critical threshold (the chloride threshold for depassivation of the steel), the passive oxide film protecting the steel breaks down and active corrosion begins. Expansive corrosion products crack and spall the cover concrete, leading to progressive structural deterioration. Preventing this requires: a sufficiently impermeable concrete (achieved through low water/binder ratio and the use of GGBS or PFA); adequate cover depth; and sufficient concrete quality (strength, compaction, and curing). BS 8500 sets minimum requirements for all three in its prescriptive approach to XS2 specification.
Under BS 8500-1:2015+A2:2019 Table A.3, the minimum concrete specification for XS2 exposure depends on the intended design service life (50 or 100 years) and the binder combination selected. The key requirements for a 100-year design life with CEM I + 50% GGBS (the most common UK specification for marine infrastructure) are:
The use of Ground Granulated Blast-furnace Slag (GGBS) as a partial replacement for Portland cement (CEM I) is strongly recommended — and in many cases mandated by BS 8500 — for XS2 concrete. GGBS provides three critical benefits for marine exposure:
Pulverised Fuel Ash (PFA) provides similar (though less pronounced) benefits to GGBS for chloride resistance and is also permitted under BS 8500 for XS2 exposure, typically at 25–35% replacement levels. At higher replacement levels (above approximately 35%), BS 8500 applies an efficiency factor (k-value) that effectively limits the durability credit given to PFA above this threshold.
The table below summarises the minimum concrete specification requirements for XS2 exposure class under BS 8500-1:2015+A2:2019 Table A.3 for 50-year and 100-year design service lives, by binder combination. All values are minimum requirements — actual mix designs should include appropriate margins and should be confirmed by a concrete technologist.
| Binder Combination | Design Life | Min. Strength Class | Max. w/b Ratio | Min. Binder (kg/m³) | Min. Nominal Cover (mm) | Notes |
|---|---|---|---|---|---|---|
| CEM I only (100% Portland) | 50 years | C35/45 | 0.40 | 360 | 50 | Not recommended; poor long-term chloride resistance; high embodied carbon |
| CEM I only (100% Portland) | 100 years | C40/50 | 0.35 | 380 | 65 | Very high binder content; significant heat of hydration; not preferred for marine |
| CEM I + 35% GGBS (IIB-S) | 50 years | C32/40 | 0.45 | 320 | 45 | Useful for thinner sections; less chloride benefit than 50% GGBS |
| CEM I + 35% GGBS (IIB-S) | 100 years | C35/45 | 0.40 | 340 | 60 | Adequate for many applications; consider upgrading to 50% GGBS for enhanced durability |
| CEM I + 50% GGBS (IIB-S) | 50 years | C28/35 | 0.45 | 320 | 40 | Most common UK XS2 specification; good balance of durability and economy |
| CEM I + 50% GGBS (IIB-S) | 100 years | C32/40 | 0.40 | 340 | 60 | Standard specification for major UK marine infrastructure 2026 |
| CEM I + 70% GGBS (IIIA) | 50 years | C25/30 | 0.50 | 300 | 35 | Very good chloride resistance; slow strength gain; extended curing essential |
| CEM I + 70% GGBS (IIIA) | 100 years | C28/35 | 0.45 | 320 | 50 | Excellent long-term chloride resistance; very low heat; used for mass marine pours |
| CEM I + 25% PFA (IIB-V) | 50 years | C32/40 | 0.45 | 320 | 45 | PFA provides moderate chloride resistance benefit; less effective than GGBS at equivalent levels |
| CEM I + 25% PFA (IIB-V) | 100 years | C35/45 | 0.40 | 340 | 60 | Acceptable for 100-year life; GGBS generally preferred for XS2 |
| CEM I + 35% PFA (IIB-V) | 100 years | C32/40 | 0.40 | 340 | 55 | Higher PFA replacement; similar durability to 35% GGBS but less widely specified |
| SRPC (Sulfate Resisting PC) | 50 years | C35/45 | 0.40 | 360 | 50 | Only where sulfate attack (XA class) also applies; does not improve chloride resistance |
Source: BS 8500-1:2015+A2:2019 Table A.3 and Concrete Society TR61. Nominal cover includes a 10mm deviation allowance (Δcdev) over the minimum structural cover (cmin,dur). All values are for reinforced concrete (RC); unreinforced concrete (PC) has different requirements. Confirm with structural engineer and concrete technologist for project-specific design.
| Mix Specification | Supply Method | Cost per m³ (excl. VAT, 2026) | Notes |
|---|---|---|---|
| C32/40, 50% GGBS, XS2, S3 | Ready-mix (truck) | £140–£190/m³ | Most common XS2 specification; includes GGBS addition; delivery extra |
| C35/45, 50% GGBS, XS2, S3 | Ready-mix (truck) | £155–£210/m³ | Higher strength class; lower w/b ratio; slightly higher cement content |
| C32/40, 70% GGBS, XS2, S3 | Ready-mix (truck) | £135–£185/m³ | Lower CEM I content reduces cost; excellent chloride resistance |
| C32/40, 50% GGBS, XS2, F5 (SCC) | Ready-mix / tremie | £165–£225/m³ | Self-compacting for tremie or congested reinforcement; higher binder content |
| C40/50, CEM I only, XS2, S3 | Ready-mix (truck) | £155–£215/m³ | Not recommended for XS2; high cost and poor durability vs GGBS alternative |
| XS2 compliant mix (any) | Offshore / remote site delivery | +£40–£120/m³ premium | Additional cost for barge, pump, or helicopter delivery; site-specific |
XS2 concrete and marine durability resources UK 2026: The Concrete Centre – Durability Guidance | Mineral Products Association (MPA) | BSI – BS 8500 / BS EN 206 | MPA Concrete – Exposure Class Guidance | CEMEX – Specialist Concrete Mixes
| Item / Consideration | Typical Cost / Impact (2026) | Notes |
|---|---|---|
| Ready-mix delivery (coastal / marine site) | £150–£500 per delivery | Higher than standard sites; road access to coastal sites often restricted; tidal windows may limit delivery times |
| Concrete pump hire (coastal) | £500–£1,200/day + per m³ | Often essential for marine pours; boom or line pump to point of placement; ensure pump mix suitability |
| Tremie pipe system (underwater pour) | £800–£3,000 mobilisation + £20–£40/m³ | Required for concrete placed below water; retarded mix essential; specialist contractor needed |
| Marine-grade stainless steel reinforcement | £3,500–£6,000/tonne | Grade 316 or duplex stainless; eliminates corrosion risk; specified for most demanding XS2/XS3 applications |
| Epoxy-coated reinforcement | £900–£1,400/tonne | Fusion-bonded epoxy coating; reduces chloride-induced corrosion risk at lower cost than stainless; check coating integrity after cutting |
| Cathodic protection system | £50–£200/m² of concrete surface | Impressed current or sacrificial anode systems; used in rehabilitation and in new construction for highest durability requirement |
| Concrete cube testing (per set of 6) | £100–£250 per set | Essential QA for marine structural concrete; test at 7, 28, and 56 days; use UKAS-accredited laboratory |
| Chloride diffusion testing (RCPT / NT BUILD 492) | £150–£400 per specimen | Rapid Chloride Permeability Test or NT Build 492 migration test; confirms mix achieves required permeability for XS2 |
| Concrete durability assessment / mix design review | £500–£2,000 | Specialist concrete technologist review of proposed mix against BS 8500 XS2 requirements; essential for major marine infrastructure |
| Tidal window working restrictions | Project-specific; significant programme and cost impact | Many marine concrete pours must be completed within a tidal window; requires precise planning and may require retarder admixture to extend workability |
| Coarse aggregate (marine / chloride-washed) | +£5–£15/tonne vs standard aggregate | Marine dredged aggregate must be washed to EN 12620 acid-soluble chloride limits (<0.01% for reinforced concrete) |
| Silica fume / microsilica addition | +£15–£40/m³ | 5–10% silica fume further reduces chloride diffusivity and permeability; used in highest-specification XS2/XS3 applications |
XS2 applies specifically to concrete that is permanently submerged below the lowest astronomical tide (LAT) in seawater or saline water. This includes: sub-sea pile shafts and pile toes; submerged foundations of piers, jetties, and offshore structures; culverts below LAT; and submerged harbour walls and caissons. Concrete in the tidal zone (between LAT and HAT) is classified XS3 — the more aggressive marine class. Above HAT within coastal salt spray range is XS1.
In XS2 (permanently wet) conditions, chloride transport is dominated by ionic diffusion — chloride ions move from the high-concentration seawater into the lower-concentration concrete pore solution along a concentration gradient. This is a slower process than the capillary absorption that drives chloride ingress in XS3 (wet-dry cycling). The chloride diffusion coefficient (D) of XS2 concrete must be low enough that the chloride threshold at the reinforcement is not reached within the design service life.
Concrete with 50% GGBS typically has a chloride diffusion coefficient approximately 5–10 times lower than equivalent 100% CEM I concrete tested at 28 days, and the difference increases with time as GGBS continues to hydrate. At 70% GGBS, the diffusion coefficient can be 10–20 times lower than CEM I. This dramatic reduction in permeability is why GGBS is the binder of choice for XS2 and XS3 marine concrete in UK practice.
The nominal cover to reinforcement for XS2 concrete with a 100-year design life is 60–75mm depending on the binder combination (per BS EN 1992-1-1 UK NA). This is significantly higher than covers required for non-marine exposure classes. The nominal cover includes a 10mm deviation allowance (Δcdev) over the minimum durability cover (cmin,dur). Achieving the specified cover consistently in marine construction requires careful spacer selection, placement inspection, and quality control.
The maximum water/binder ratio of 0.40 for XS2 100-year design life (with 50% GGBS) is significantly lower than domestic concrete mixes. This low w/b ratio is essential to achieve the low porosity and chloride diffusivity required for adequate durability. Achieving w/b ≤ 0.40 in practice requires careful water measurement, accounting for aggregate moisture content, and typically the use of a superplasticiser admixture to maintain workability at low water content.
For reinforced concrete in XS2 exposure, BS EN 206 requires a maximum chloride content of Cl 0.20 — meaning the total chloride content of the fresh concrete mix must not exceed 0.20% by mass of cement. This limits the use of marine-dredged aggregates unless they have been thoroughly washed to reduce chloride content below the applicable limits in BS EN 12620. Calcium chloride admixtures (chloride-based accelerators) must never be used in reinforced concrete.
Concrete placed underwater using a tremie pipe must have a highly fluid consistency (typically S4–F5) to flow from the pipe end without segregating, and must be retarded to maintain workability throughout the pour without the aid of vibration. Tremie concrete typically has a higher binder content than equivalent poured-in-formwork concrete (to maintain cohesion), a superplasticiser, and a retarding admixture calibrated to the anticipated pour duration and temperature. The tremie pipe must always be kept embedded in the fresh concrete — never lifted above the concrete surface during pouring.
GGBS concrete requires significantly longer and more consistent curing than 100% CEM I concrete to develop its chloride resistance. The Concrete Society recommends a minimum of 7 days wet curing for 50% GGBS XS2 concrete — extended to 14 days or more for 70% GGBS mixes or in cold weather. Premature drying of GGBS concrete before adequate hydration has occurred can result in a surface zone with poor chloride resistance, undermining the purpose of using GGBS in the first place. Curing compounds, wet hessian, and polythene sheeting are all effective methods.
Silica fume (microsilica), typically at 5–10% addition, further reduces chloride diffusivity and dramatically reduces the concrete's permeability. It is used in the most demanding marine applications — particularly where 100-year or longer service lives are required, or where the depth of concrete cover is limited by structural or architectural constraints. Silica fume significantly increases binder reactivity and heat of hydration (partially offsetting GGBS's low-heat benefit) and improves early strength gain. Always confirm silica fume compatibility with the GGBS content and admixture system.
XS2 marine concrete requires a rigorous QA programme including: concrete cube testing at 7, 28, and 56 days (56-day results are important for GGBS mixes which continue gaining strength); chloride diffusion testing (RCPT or NT Build 492 migration test) to confirm the mix achieves the required permeability; cover measurements using a covermeter before and after concrete placement; and concrete delivery ticket inspection to confirm every load conforms to the specified mix. Major marine infrastructure projects typically employ a third-party concrete inspector on site during all pours.
For the most demanding XS2 applications — particularly where concrete cover is limited, the structure is inaccessible for future maintenance, or where a very long service life (150+ years) is required — stainless steel reinforcement (Grade 316L or duplex 2205) eliminates the risk of chloride-induced corrosion entirely. The chloride threshold for stainless steel is orders of magnitude higher than for carbon steel. The cost premium (approximately £3,500–£6,000/tonne vs £600–£850/tonne for carbon steel) is often justified by whole-life cost analysis for critical marine infrastructure.
BS 8500 Table A.3 provides a prescriptive approach to XS2 specification — defining minimum mix requirements (strength, w/b ratio, binder content) that are deemed to provide adequate durability. Alternatively, a performance-based approach (BS EN 206 Clause 5.3.3) permits a custom mix design that demonstrates durability through testing (e.g. chloride diffusion testing) rather than prescriptive compliance. Performance-based specification is increasingly used for major marine infrastructure where a site-specific chloride diffusion model (such as the Life-365 or DuraCrete approach) is used to optimise the mix design for the specific exposure conditions and design life.
| Class | Description | Typical Locations | Min. Strength (100yr, 50% GGBS) | Max. w/b (100yr) | Min. Cover (100yr, nominal) | Key Durability Threat |
|---|---|---|---|---|---|---|
| XS1 | Exposed to airborne salt; no direct seawater contact | Coastal structures, buildings within ~1km of sea | C28/35 | 0.45 | 45mm | Chloride ingress from salt-laden air |
| XS2 | Permanently submerged in seawater | Sub-sea piles, submerged foundations, harbour walls below LAT | C32/40 | 0.40 | 60mm | Chloride diffusion through saturated concrete |
| XS3 | Tidal, splash, and spray zones | Intertidal piles, jetty decks, sea walls, breakwaters | C35/45 | 0.38 | 65–75mm | Chloride absorption + freeze-thaw + wetting/drying cycling |
| XC2 | Wet, rarely dry (non-marine) | Buried below-ground structures, water-retaining | C25/30 | 0.55 | 40mm | Carbonation-induced corrosion |
| XC3/XC4 | Moderate-high humidity / cyclic wet-dry | External structures not in XS classes | C30/37 | 0.50 | 45mm | Carbonation to reinforcement |
| XD2 | Wet, rarely dry – chlorides (non-marine) | Swimming pools, below-ground de-icing salt exposure | C32/40 | 0.45 | 50mm | Non-marine chloride ingress |
| XD3 | Cyclic wet-dry – chlorides (non-marine) | Bridge decks, car park slabs, road splash zone | C35/45 | 0.40 | 55mm | De-icing salt chloride ingress + freeze-thaw |
| XF4 | High water saturation + de-icing salt | Road surfaces, bridge decks in freeze-thaw zone | C35/45 | 0.40 | — | Freeze-thaw cycling with chloride; air entrainment required |
Values for 100-year design life with CEM I + 50% GGBS binder combination where applicable. Covers include 10mm Δcdev deviation allowance. Source: BS 8500-1:2015+A2:2019 and BS EN 1992-1-1 UK National Annex. Always confirm exposure class assignment with the structural engineer and concrete technologist — multiple exposure classes often apply simultaneously to a single element.
XS2 is one of the chloride-from-seawater exposure classes defined in BS EN 206 and BS 8500. It applies to reinforced or prestressed concrete that is permanently submerged in seawater — below the lowest astronomical tide level — where the concrete is continuously saturated with seawater containing approximately 19,000–20,000 mg/litre of chloride ions. XS2 is less aggressive than XS3 (tidal, splash, and spray zones) but more aggressive than XS1 (airborne salt only). Typical XS2 applications include sub-sea pile shafts, submerged harbour walls, underwater foundations, jetty pile toes, and any reinforced concrete structure below the permanent water line in a marine environment.
For a 100-year design service life — standard for major marine infrastructure — the recommended XS2 concrete specification using CEM I + 50% GGBS (the most common UK approach) is: minimum strength class C32/40; maximum water/binder ratio 0.40; minimum total binder content 340 kg/m³; and nominal cover to reinforcement 60mm minimum. In practice, most XS2 mixes for major infrastructure use 360–400 kg/m³ total binder to provide a margin above the minimum, a superplasticiser to achieve adequate workability at w/b ≤ 0.40, and 50–70% GGBS replacement to maximise chloride resistance. The mix must be specified as a designed mix to BS EN 206 / BS 8500 from a quality-certified concrete producer — site-mixed concrete is not appropriate for XS2 structural applications.
GGBS (Ground Granulated Blast-furnace Slag) is used in XS2 marine concrete primarily because it dramatically reduces chloride diffusivity — the rate at which chloride ions can penetrate through the concrete to reach the reinforcement. The denser, less porous microstructure produced when GGBS hydrates with calcium hydroxide from Portland cement hydration creates a concrete with a chloride diffusion coefficient approximately 5–10 times lower than equivalent 100% CEM I concrete. This directly increases the time before chlorides reach a critical concentration at the reinforcement surface, extending the corrosion-free service life. Additionally, GGBS reduces heat of hydration (beneficial for thick marine elements where thermal cracking is a risk), reduces embodied carbon by approximately 43% at 50% replacement, and under BS 8500 allows a lower minimum strength class and binder content than CEM I-only mixes for equivalent durability performance.
The nominal cover to reinforcement for XS2 concrete under the UK National Annex to BS EN 1992-1-1 (Eurocode 2) depends on the binder combination and design service life. For a 100-year design life with CEM I + 50% GGBS, the nominal cover is 60mm. With CEM I + 70% GGBS, it reduces to approximately 50mm. With 100% CEM I (not recommended), it increases to 65mm. These nominal values include a 10mm deviation allowance (Δcdev) over the minimum structural cover — so the minimum structural cover (cmin,dur) is 10mm less than the nominal cover shown. Achieving the specified cover consistently in marine concrete construction requires careful spacer installation and cover measurement before concrete placement.
XS2 and XS3 are both BS EN 206 marine chloride exposure classes, but they describe very different environments. XS2 (permanently submerged) describes concrete that is always below the water line — continuously saturated with seawater. In this condition, chloride transport is driven primarily by ionic diffusion, which is relatively slow. XS3 (tidal, splash, and spray) is significantly more aggressive — concrete in this zone alternately wets and dries as the tide rises and falls, and is subject to wave action and spray. The cyclical wetting and drying dramatically accelerates chloride ingress (through capillary absorption when dry, then locking in chlorides when wet), and in northern latitudes freeze-thaw cycling adds additional mechanical damage. For this reason, BS 8500 requires a higher minimum strength class, lower w/b ratio, and greater nominal cover for XS3 than for XS2. The tidal zone (between LAT and HAT) is always XS3; the permanently submerged zone is XS2.
Marine-dredged aggregates can be used in XS2 concrete provided they have been washed and processed to meet the chloride content limits of BS EN 12620. The maximum acid-soluble chloride content for aggregate used in reinforced concrete under BS EN 12620 is 0.01% by mass. Unwashed or inadequately washed marine aggregate may contain significantly higher chloride levels that could contribute to the concrete's chloride content, pushing it above the Cl 0.20 limit required for XS2 reinforced concrete. Always request a chloride test certificate from your aggregate supplier and confirm compliance before use. The ready-mix plant should routinely check aggregate chloride levels as part of their production control procedure.
Concrete placed below the water surface for XS2 applications must be placed using a tremie pipe — a steel tube of sufficient diameter (typically 150–250mm) that is lowered to the bottom of the pour and gradually raised as concrete is pumped or gravity-fed through it. The critical rule is that the pipe must always be embedded in the fresh concrete — if the pipe is lifted above the concrete surface, seawater can enter and contaminate or dilute the mix. The mix must be highly fluid (S4 or self-compacting/F5) to flow from the pipe end without vibration, and must be retarded to maintain workability throughout the pour. Tremie concrete typically requires a higher binder content and superplasticiser dosage than equivalent formed concrete. Alternative underwater placement methods include underwater skips and concrete pumping via sealed hose, but tremie remains the most common method for structural marine foundations.
XS2 concrete requires extended curing compared to non-marine concrete, particularly when GGBS is used. The minimum recommended curing periods are: 50% GGBS mix: minimum 7 days of wet curing (polythene sheeting, wet hessian, or ponded water); 70% GGBS mix: minimum 14 days wet curing. In cold weather (below 10°C), double the above periods. The importance of curing GGBS concrete cannot be overstated — GGBS hydration is strongly temperature-dependent and proceeds much more slowly than Portland cement hydration, particularly in the cold conditions typical of UK coastal construction. Inadequate curing of GGBS concrete can result in a surface zone with poor chloride resistance, directly undermining the primary purpose of specifying GGBS for marine durability.
For any significant XS2 marine infrastructure project, the involvement of a specialist concrete technologist or durability engineer is strongly recommended and for major projects is effectively essential. The concrete technologist will: confirm the correct exposure class designation for each element; specify the mix design requirements to BS 8500; review the ready-mix plant's proposed mix design and quality documentation; oversee the QA testing programme (cubes, chloride diffusion testing, cover measurements); and confirm that the as-built concrete conforms to the specification. For minor works (small repairs, isolated elements with limited consequences of failure), prescriptive compliance with BS 8500 Table A.3 by a competent structural engineer may be sufficient — but for major marine infrastructure with 100-year design life requirements, specialist durability input is non-negotiable.
XS2-compliant ready-mix concrete costs approximately £140–£190 per m³ for a standard C32/40, 50% GGBS, S3 consistency mix in South East England in 2026, plus delivery charges of £150–£500 depending on site accessibility. The premium over standard structural concrete (approximately £110–£155/m³ for C25/S3) reflects the higher binder content, GGBS addition, superplasticiser, and the additional quality assurance and documentation requirements for marine concrete. For remote or offshore sites, additional premiums of £40–£120/m³ apply for the logistics of concrete delivery by barge, pump, or other non-standard means. Tremie pours (underwater placement) cost an additional £20–£40/m³ in specialised equipment and labour. Total concrete costs for XS2 marine projects typically represent only a fraction of overall project costs — with access, tidal working, and structural complexity usually dominating the budget.
XS2 structural concrete requires a comprehensive testing programme to demonstrate conformity with the specification. Minimum requirements include: Compressive strength testing — minimum one set of six 150mm cubes per 50 m³ (or per day's pour if less), tested at 7 and 28 days (and 56 days for GGBS mixes), at a UKAS-accredited laboratory; Fresh concrete testing — slump or flow at point of delivery to confirm workability class; Delivery ticket inspection — every load must be accompanied by a BS EN 206 delivery ticket confirming the specified mix designation, binder type and content, w/b ratio, and batch reference; Chloride diffusion testing (RCPT or NT Build 492) — at mix design approval stage and periodically during production for major projects; and Cover measurement — covermeter survey after reinforcement fixing and before concrete placement. For prestressed concrete elements, additional requirements for chloride content of mixing water and aggregates apply.
Additional XS2 and marine concrete resources UK 2026: The Concrete Centre – Exposure Classes | BSI – BS 8500 / BS EN 206 | Mineral Products Association | Institution of Structural Engineers | Hanson REGEN GGBS | CEMEX UK – Marine Concrete