00-ZA-E-85135_0

COMPANY / PLANT LOCATION BRASS FERTILIZER / NIGERIA PROJECT Early Work for EPC for Ammonia, Urea Methanol Project

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DOCUMENT TITLE

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FIREPROOFING CRITERIA

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FIREPROOFING CRITERIA

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Issued for Review - IFR Description

V.Provenzano Prepared

L.Tullio Checked

V.Provenzano Approved

23/10/2014 Date

This document is prepared by Saipem SpA for Brass Fertilizer. It contains proprietary and confidential information of Saipem and/or of the Technologies Licensors who will safeguard their rights according to the civil and criminal provisions of the law. It shall neither be disclosed to third parties nor used for purposes other than those for which it has been disclosed.

COMPANY / PLANT LOCATION BRASS FERTILIZER / NIGERIA PROJECT Early Work for EPC for Ammonia, Urea Methanol Project DOCUMENT TITLE FIREPROOFING CRITERIA

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CONTENTS SCOPE

3

1

DEFINITIONS

4

1.1

4

Abbreviations

2

PROJECT IDENTIFICATION

5

3

REFERENCES

5

3.1

PROJECT Documents

5

3.2

Nigerian laws and regulations

5

3.3

International Codes and Standards:

5

4

_____

5

6

DEFINITION AND GENERAL REQUIREMENTS

6

4.1

Hazardous fluids

6

4.2

Source of hazard

6

4.3

Fireproofing zone

7

4.4

Protection time

7

4.5

Standard reference curves

8

STRUCTURES, EQUIPMENT AND COMPONENT TO BE FIREPROOFED

10

5.1

General considerations

10

5.2

Steel supports and supporting structures

10

5.3

Steel supports for piping (piperacks and other supporting structures)

11

5.4

Air Coolers supporting structures

11

5.5

Furnace and boiler support structures

12

5.6

Supports for compressors considered sources of hazard

12

5.7

Electrical, instrumentation and control systems

12

5.8

Emergency shut-off valves

12

5.9

Hot surfaces

13

5.10 Insulated equipment

13

5.11 Requirements for Buildings 5.11.1 Fire and Smoke Stopping System

13 14

SELECTION OF FIREPROOFING MATERIALS

22

6.1

General considerations

22

6.2

Protective materials

23

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SCOPE The purpose of this document is to define the reference criteria for the definition of requirements for the application of passive fire protection (fireproofing). According to CONTRACT (Ref. [1.]), passive fire protection of the plant will be designed following CONTRACTOR’s standard. In case of fire, fireproofing is used to protect structures/items, the collapse of which could cause a dangerous increase in the severity of the accident. The fireproofing criteria detailed in this document refer to accidental scenarios resulting in a severe pool fire developing. The main substance handled in the Ammonia and Urea Process units is ammonia, for which the following is remarked: •

Ammonia has a very narrow flammability range;

•

Ammonia is extremely difficult to ignite;

•

International standards define flammable fluids as easily to ignite; international fluid classification standards classify ammonia ignitability as extremely low;

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Based on the above, ammonia shall not be taken into account for fireproofing purposes. The criteria defined in this document should be regarded as the minimum requirements to ensure a uniform safety level in all projects. Both the identification of hazard sources and the size of fireproofing zones are therefore beyond the considerations related to risk analysis, so neither the probability of an event nor the presence of systems to reduce it’s effects (e.g. elimination of flanged connections, removal/confinement of spilt flammable fluids, blocking leaks, etc.) are taken into account This document does not consider the following: •

Cold/heat insulation for process or storage purposes;

•

Protection against accidental spillage of cryogenic liquids (“cold-splash”), which is necessary to avoid weakening the metal structures that could be hit;

•

Offshore plants;

•

Pipelines for the transport of hazardous fluids (outside plant battery limits).

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DEFINITIONS COMPANY

Brass Fertilizer

CONTRACTOR

Saipem S.p.A.

CONTRACT

Contract agreement entered between COMPANY and CONTRACTOR

PROJECT

Early Work for EPC for Ammonia, Urea and Methanol Project

VENDOR

Entity that provides equipment and related services part of the WORK according to the CONTRACTOR purchase order.

WORKS

Plant to be supplied, as well as the installation Related Services to be carried out by CONTRACTOR under the CONTRACT

Abbreviations API

American petroleum Institute

ASTM

American Society for Testing and Materials

BDV

Blow down valve

ESDV

Emergency Shut down valve

EDP

Emergency Depressurization Plant

F&G

Fire and Gas

HAC

Hazardous Area Classification

HSE

Health, Safety and Environmental Department

NBC

National Building Code

NFPA

National Fire Protection Association

UL

Underwriters laboratories

UNI

Ente Italiano Normalizzazione

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PROJECT IDENTIFICATION Brass Fertilizer Company Limited (COMPANY), a Nigerian company, is in the process of developing a state of art fertilizer project at Brass Island in the state of Bayelsa, Nigeria. The Plant comprises the Inside Battery Limits (ISBL), the Outside Battery Limits (OSBL) units and other facilities, including the utilities and the off-site facilities necessary for the operation of a 2,200 MTPD Ammonia Plant, a 3,850 MTPD Urea & Granulation Plant and a 5,000 MTPD Methanol Plant.

3

REFERENCES 3.1

_____

3.2

PROJECT Documents [1.]

Early Work for Ammonia, Urea and Methanol Project NIGERIA PROPOSAL 14GM033/1

[2.]

00-ZA-E-09022 - Basic Engineering Design Data (BEDD)

[3.]

00-ZA-E-09710 - Project HSE Requirements

[4.]

00-ZA-E-85010 - F&G Detection criteria

[5.]

00-ZA-E-85135 - Fireproofing criteria

[6.]

00-ZA-E-85570 - Active Fire Protection Systems design basis

[7.]

Brass Fertilizer Urea And Assessment – Dec. 2013

Plant

Environmental

Impact

Nigerian laws and regulations [8.]

3.3

Methanol

National Building Code - 2006

International Codes and Standards: [9.]

Contractor “Design Practice - Fireproofing” PRG.AF.FPR.0004, April 2011

[10.] NFPA 325, “Fire Hazard Properties of Flammable Liquids, Gases, and Volatile Solids”, 1994 [11.] UL 1709, “Standard for Rapid Rise Tests of Protection Materials for Structural Steel”, 2007 [12.] ASTM E 1529, “Standard Test Methods for Determining Effects of Large Hydrocarbon Pool Fires on Structural Members and Assemblies”, 2010 [13.] API 6FA, “Fire Test for Valves”, 1999 [14.] UNI 9503, " Analytical fire resistance assessment of steel structural elements", 2007 _____________________________



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DEFINITION AND GENERAL REQUIREMENTS 4.1

Hazardous fluids In order to identify potential hazard sources, the following fluids are defined as “hazardous” for fireproofing purposes: a.

Flammable liquids (liquids with a flash point of less than 55°C).

b.

Combustible liquids (flash point of 55°C or higher) operating at temperatures above their flash point, or within 8°C below their flash point.

c.

Flammable liquids, processed at temperatures greater than 315°C or greater than their auto-ignition temperature.

d.

Pyrophoric liquids (materials that spontaneously ignite upon contact with air).

For the determination of the chemical-physical properties of the substances necessary for the classification, reference can be made to the data sources listed in Ref. [10.].

_____ 4.2

Source of hazard Any equipment containing hazardous fluids as defined in section 4.1, within the limits established in the following paragraph, is defined as a “source of hazard”, since it could generate a sustained fire. The following types of equipment containing/processing hazardous fluids are normally identified as sources of hazard: •

Equipment with hazardous fluids ≥5,5t;

•

Pumps with flow rates ≥45m3/h;

•

Process heaters/furnaces (pipe side).

Compressors for flammable gases having power rating ≥150kW due to the risks associated with the amount of lube oil present in the system are also considered sources of hazard, unless they are protected by automatic fire fighting systems. In this context, piping containing hazardous fluids is not considered as a source of hazard. It is however considered in the context of defining the systems to be protected, as specified in section 5.3. In this context, gas turbine and steam turbine are not to be considered source of hazard.

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Fireproofing zone The zone surrounding a source of hazard within which, in case of fire, other equipment, machinery or support structures could be involved, is defined as “fireproofing zone”. The size of the fireproofing zone is normally established as follows: Horizontally for a distance of 6m from the source of hazard; Vertically

up to a height of 8m above ground level or above the first continuous floor 1 located below the source of hazard.

A graphical representation of the above is shown in Figure 1. The following zones shall also be considered as fireproofing zones: • The area inside the retention pond of a source of hazard. The fireproofing zone extends from ground level to a height of 8m inside the pond; •

The area that horizontally extends 1m from the borders of superficial and/or uncovered channels used for transferring hazardous fluids to safe areas, for a height of 2m;

•

The space that horizontally extends for 30m from marine intake/outlet manifolds or terminals in which hazardous fluids are processed. The vertical height of the fireproofing zone shall be defined according to the type of structure to be protected (e.g. Marine terminal, pier, ship load/discharge manifolds, etc.), evaluating the possibility that the risk zone extends from the water surface up to and including the height of the jetty.

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The horizontal distance for pumps and compressors is measured from the seal; for all other equipment, it is measured from the outer surface of the equipment itself. 4.4

Protection time The “protection time” is defined as the period of time for which fireproofing shall maintain the metal surface at temperatures that do not compromise the stability of the structure or equipment exposed to fire, allowing the plant/unit to be safely shutdown and fire brigades to intervene. The general requirements in terms of protection times to be applied to structures/equipment located in the fireproofing zone are as follows:

1 Continuous floor is intended as any non-perforated surface larger than 6 meters upon which an accidentally released fluid could accumulate. In case the floor is less than 6 meters and not curbed, the ground floor should be considered as accumulation zone. _____________________________



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•

protection time of 90 minutes up to a height of 4.5m (up to 8m for air-cooler support structures, even if located above the piperack);

•

protection time of 30 minutes for heights from 4.5m to 8m.

Section 5 details fireproofing requirements for specific structures; section 6 reports information on the methods and types of fireproofing to be applied. 4.5

Standard reference curves Fireproofing characteristics are determined by making reference to the test cases of a hydrocarbon fire with a temperature/time profile as defined in the UL-1709 or ASTM E 1529 standards. With reference to the above fire tests, UL-1709 or ASTM E 1529, and for the test duration (90 minutes and 30 minutes protection time, as specified in section 4.4), the fireproofing must guarantee that the temperatures of steel structures remain below 300°C on metal surfaces not directly exposed to the flame.

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Figure 1 – Extent of fireproofing zone VISTA LATERALE SIDE VIEW

8m

8m

CONTINUOUS PAVIMENTO FLOOR CONTINUO

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LIVELLO DEL GROUND TERRENO LEVEL

TOP VIEW PIANTA

6m (*) 6m (*)

(*) distanza 15m for perpressurized stoccaggi in storages pressioneof (*) distanceincrementata increased toa 15m 3 con volume di liquido pericoloso hazardous fluids with capacity >50m greater than 50m3

HAZARD SOURCE SORGENTE DI PERICOLO FIREPROOFING ZONE AREA A PERICOLO DI INCENDIO

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STRUCTURES, EQUIPMENT AND COMPONENT TO BE FIREPROOFED The following sections from 5.2 to 5.8 define the criteria for identifying the equipment, structures and components for which fireproofing shall be provided. Section 5.11 refers to requirements for buildings. 5.1

General considerations Fireproofing shall only be applied to the parts of structures that fall within a fireproofing zone (see section 4.3). No fireproofing is required for equipment, structures and components outside of the fireproofing zones. When fireproofing is applied to vessels surface, it can be considered during the design of PSV to reduce maximum flow rate in case of external fire.

5.2 _____

Steel supports and supporting structures Fireproofing must be provided for skirts/legs/saddles and steel support structures of all equipment identified as sources of hazard. The skirts/legs/saddles, when required, and steel support structures of the following equipment shall also be protected: •

equipment containing non-hazardous fluids, having an overall mass (equipment + fluid) ≥10t;

•

equipment containing hazardous fluids (as per section 4.1), in quantities ≥2t;

•

equipment containing toxic fluids in quantities ≥1t.

Large items of equipment (greater than 10t) containing hazardous or nonhazardous fluids shall be considered because, in case of collapse, they could result in an “escalation” of the initial accident. Equipment containing significant amounts of toxic fluids (greater than 1t) shall be considered because a possible loss of containment, caused by a nearby fire, would obstruct the intervention of fire-fighting squads. The supporting structures shall be protected for a period of 90 minutes up to a height of 4.5m above ground level or the first continuous floor, and for a period of 30 minutes for heights from 4.5m to 8m (see Fig. 2). The main steel supporting structures (columns and beams that directly or indirectly support the equipment), shall be protected within the defined ranges. Secondary beams, wind bracing, stairs and walkways do not need fireproofing. _____________________________



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Vertical vessels with a diameter exceeding 1.4m (see Fig. 3) shall have skirts protected both internally and externally. Only the external protection of skirts needs to be provided for vertical vessels with a diameter less than 1.4m. For horizontal vessels, protection of the saddles is only required if the distance between the bottom of the equipment and the concrete pier (vertical support) is greater than 0.3m. In this case, the saddle must be protected for a period of 90 minutes up to a height of 4.5m from the fire plane and for a period of 30 minutes for heights from 4.5m to 8m (see Fig. 4).

5.3

Steel supports for piping (piperacks and other supporting structures) Fireproofing shall be provided for the structures that support the following:

_____

•

piping containing flammable or combustible liquids, with a diameter greater than 6”;

•

piping containing toxic fluids (amounts of toxic fluids greater than 1t);

•

blowdown/flare headers;

•

firefighting pipework;

•

piping containing oxygen.

If the height of the first horizontal plane carrying piping is less than 4.5m, the fireproofing must guarantee protection for a period of 90 minutes up to a height of 0.5m beneath the intrados of the first horizontal supporting beam. The upper part, up to a height of 8m, shall be protected for a period 30 minutes (see Fig. 5). The main steel supporting structures (columns and beams) shall be protected within the defined ranges. Longitudinal connections, secondary members and wind bracings do not need fireproofing.

5.4

Air Coolers supporting structures The supporting structures for air-coolers shall be protected for a period of 90 minutes up to a height of 8 m. The main steel supporting structures (columns and beams, including the longitudinal connections that directly or indirectly carry the air-coolers) shall be protected within the defined ranges (see Fig. 6). Side frames, beams supporting tube bundle, secondary members and wind bracings do not need fireproofing.

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Furnace and boiler support structures The support structures for furnaces and boilers shall be protected for a period of 90 minutes up to a height of 0.5m beneath the intrados of the horizontal supporting beam in contact with the equipment, but nevertheless not higher than 4.5m above ground level (or the first continuous floor). No fireproofing is required above 4.5m. The main steel supporting structures (columns) shall be protected within the defined ranges (see Fig. 7). Longitudinal connections, secondary members and wind bracings do not need fireproofing.

5.6

Supports for compressors considered sources of hazard The metal structures supporting compressors classified as sources of hazard shall have the main columns and beams protected for a time of 90 minutes up to a height of 4.5m above the ground or the first continuous floor. Shelter columns will be fireproofed if within 6 m from compressor/oil reservoir and if they support heavy crane bridge (see also 5.2)

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5.7

Electrical, instrumentation and control systems Fireproofing shall be provided for electrical feed systems and instrumentation and control systems required for handling an emergency, when the failure of the above systems due to exposure to fire does not allow to put the unit/plant in safe conditions. The fireproofing shall guarantee the functionality of the components exposed to fire for a period of 30 minutes. Fireproofing is not required if the shutdown systems have a “failsafe” configuration and/or cables are “fire-resistant”, and the unit is placed in safe conditions.

5.8

Emergency shut-off valves Fireproofing shall be provided for emergency shut-off valves (ESDV and BDV) in toxic or flammable service, including actuator, motor and wiring. In order to guarantee the time for operator intervention to fully open/close the valves, the required protection time for the emergency shut-off valves shall be 30 minutes. Valves or other components designed to be “failsafe” and “firesafe” (valves designed in accordance e.g. with API 6FA, Ref. [13.]) do not need additional fireproofing. _____________________________



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Hot surfaces Any hot or ignition-triggering surfaces are also to be identified if a combustible liquid (even if not classified as a hazardous fluid, e.g. lube oil) could accidentally be released by nearby equipment (less than 6m) and ignited (i.e. brought to a temperature above the auto-ignition). In this case, insulation of the hot surfaces (to avoid ignition) is considered adequate; fireproofing of all of the structures involved is not required, unless they are within a fireproofing zone supporting equipment to be protected as per sections 5.2, 5.3, 5.4, 5.5, 5.6.

5.10

Insulated equipment When item is insulated, due to process reasons, the fire proofing of portion of legs close to the bottom of the item need to be properly realized in order to avoid interference with insulation material, hot box etc. In particular one of the following solutions can be adopted:

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5.11

•

use of ceramic insulation and inox cover sheet;

•

use of inox cover sheet painted with intumescent material.

Requirements for Buildings According to Nigerian National Building Code (ref.[8.]) project buildings are classified as: •

Group A “Assembly”: Canteen. Fire Raiting 3 hours;

•

Group B “Business and Professional”: Administration Buildings, First Aid Building, Fire Station. Fire Raiting 2 hours;

•

Group D “Factory and Industries”: Control Room, Substation, Istrument Room, Laboratory, Workshop. Fire Raiting 3 hours;

•

Group I “Storage”: Warehouse. Fire Raiting 3 hours.

Fire separation walls are required in case of separate uses or separate buildings: •

Separated uses: The mixed uses shall be completely separated, both horizontally and vertically, by fire separation walls and floor/ceiling assemblies having a fire resistance rating corresponding to the highest fire grading prescribed for the separate uses. Each part of the building shall be separately classified to use.

•

Separate buildings: The mixed uses shall be completely separated by fire walls having a fire resistance rating corresponding to the highest fire grading prescribed for the separate uses.

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Fire and Smoke Stopping System According to ref.[7.] fire and smoke stopping system shall be provided for all the openings through which cables go. This shall include conduit ends, openings in walls, floors or ceilings, cable risers, under all electrical enclosures and switchboards and any other areas which shall prevent the fire from spreading. The system shall be applied at 3 m intervals to prevent the chimney from affecting the vertical cable systems (i.e. cable risers).

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Attachment Typicals for fireproofing structures/equipment

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Figure 2 – Fireproofing of steel support structures

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Figure 3 - Fireproofing of steel supports of vertical vessels with diameter >1.4m (1)

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Figure 4 - Fireproofing of steel supports of horizontal vessels

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Figure 5 - Fireproofing of piperacks and other piping support structures

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Figure 6 - Fireproofing of metal supports of air-coolers

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Figure 7 - Fireproofing of supports of furnaces and boilers

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SELECTION OF FIREPROOFING MATERIALS 6.1

General considerations The materials to apply as fireproofing on structures and equipment shall ensure that the protected elements do not exceed their critical temperature, for the entire period of protection specified, when subjected to a normalized fire as defined in section 4.5. The term “critical temperature” for an item is intended as the temperature at which the element in question is no longer capable of supporting the load acting on it in concomitance with a fire: the critical temperature depends both on the strength characteristics of the material and on its state of stress. Only loads that can reasonably be expected to act in concomitance with a fire are taken into account when assessing the material’s state of stress, thus excluding, with regards to the structures, the earthquake and dynamic forces transmitted by lifting equipment, and applying reduced operation live load and wind loads.

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The temperature that an element can reach during the time of exposure to fire can be analytically evaluated using for example the calculation methods given in UNI 9503 (Ref. [14.]), taking into account the physical characteristics and thickness of the fireproofing material. Alternatively, a fire-resistance test can be performed on one or more representative elements of the recurrent types, in accordance with one of the methods defined in UL 1709 or ASTM E 1529. In this test, the metal element, complete with fireproofing and subjected to a condition of significant load, is exposed to a fire that provokes ambient temperature changes, as defined in the applicable standard, during the requested protection time. The outcome of the test consists in checking that: •

the tested element has not collapsed, nor does it present deformations that compromise its reliability;

•

the temperatures measured at significant points on the element have not exceeded the maximum temperature defined by the applicable standard, this specification or the project specifications.

For fireproofing not made of ordinary or lightweight concrete, it is necessary to perform the previously mentioned test, or at least obtain from the supplier of the material documents on tests already carried out on structures similar to those for which the fireproofing is requested. When determining the critical temperature of a structural element (beam or column), the yield stress resistance of normal structural steels (ASTM A 36, S235JR, S275JR, etc.) can be considered for reference purposes; at a temperature of 400°C it is computable as 70% of that at ambient temperature, while at a temperature of 500°C this resistance is reduced by 50%. Taking into account the normal safety coefficients with respect to the yield stress applied in operating conditions, the critical temperature for the individual _____________________________



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structural elements must be less than 400°C; higher temperatures can be accepted in cases when the type of constraint on the elements, the reduction of loads applied in the exceptional situation of fire with respect to that of operation and the overall behaviour of the structure are taken into account. 6.2

Protective materials The protective materials that can be used for fireproofing can be of different types. Depending on the type of material, the protective properties can be associated with low thermal conductivity, high heating capacity, or a combination of both properties. In addition to these, when choosing the type of fireproofing material, the following characteristics should also be taken to into account:

_____

•

specific weight;

•

behaviour when directly exposed to flame (in particular, no emission of toxic substances and/or pollutants);

•

adhesion to steel;

•

resistance to atmospheric and chemical agents;

•

resistance to the action of fire-cooling lances;

•

mechanical impact resistance;

•

coefficient of expansion.

The materials normally used for fireproofing structures are cement based. The characteristics of the most used are summarized below: Normal concrete

- has good durability and mechanical resistance characteristics and its exposure to direct fire has been widely experimented; - can be found everywhere and has a relatively low cost; - thermal conductivity (1.3÷1.7W/m°C) and specific weight (2200÷2400kg/m3) are greater with respect to other materials; - normally requires formwork for casting and light metal retaining mesh for anchoring to the metal support.

Lightweight concrete

- is lighter than normal concrete (1000÷1600kg/m3) and has a lower thermal conductivity (approximately 0.8÷1.0W/m°C); - formwork not normally required; - is porous and more subject to penetration by liquids and humidity; - has less impact resistance; - unit cost is higher. _____________________________



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Cellular concrete - is lighter than normal concrete (600÷1000kg/m3) and has lower thermal conductivity (with perlite or vermiculite); - formwork not normally required; - not found everywhere; - has low mechanical strength and a higher unit cost than normal concrete.

If the fireproofing adopted for steel structures is in normal concrete with a rectangular cross-section, this shall have a thickness of at least 50mm. For special design or installation requirements (for example, structures subjected to high thermal expansion), concrete materials can be substituted by other types of protective material. The following table summarizes the main characteristics and protection methods of these families of materials:

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Light refractory coatings

Subliming paints

- lighter than traditional concrete materials; - can be sprayed on or applied over a metal retaining mesh anchored to the surface to be protected; - have low densities (550÷800kg/m3); - have low mechanical resistance and are porous (if applied outdoors, they require a protective waterproof coating). - thermal protection is provided by the passage of the paint from a solid to a gaseous state; the phenomenon starting at about 160°C and proceeding until the applied product is consumed; - the applied product maintains a high degree of elasticity; - allows localized repairs to be made following possible damage; - the prescribed application thickness varies between 8 and 20mm, according to the required level of protection.

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Intumescent products

Intumescent mastics (modified epoxy resins)

Thin-film coatings (acrylic or vinyl resins and thermoplastic products)

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- when heated to 250÷300°C, they release gas which inflates the coating forming a thermally insulating foam (thickness increases 4÷6 times); - they have high viscosity at ambient temperatures, allowing thicknesses of several mm to be applied in a single coat; - application requires “non conventional” equipment; certain structures may require the use of a reinforcing mesh; - the minimum applicable thickness is approximately 5÷6mm; - they have high solid content and high specific weights (1000÷1100kg/m3); however, the limited thickness of application allows the structure to kept light; - they possess high durability, good rust protection properties, high adhesion to the substrate and resistance to impact and abrasion; - the gases emitted can be toxic so application is only allowed in open areas; - they have high costs. - the protection mechanism is the same as that of intumescent mastics; - can be applied by spraying, roller or paintbrush, in thicknesses varying from 500µm to several mm; - current materials exhibit some sensitivity to atmospheric humidity, which undermines the product’s durability; - resistance to impact and abrasion is less than that of epoxy resin based materials; the application of these products in aggressive environments requires a top coating layer; - many products have so far only been certified for exposition to the fire curve defined in accordance with ASTM-119.

The choice of alternative materials to concrete is acceptable on the condition that they are applied in a manner that guarantees the required level of protection, and that the material has been previously certified by the competent standards authorities/bodies.

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00-ZA-E-85135_0

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