Permax Protection

FAQS

At Permax we are happy to offer our assistance and advice for your structural steel fire protection requirements. Our industry expertise has led us to compile a collection of the questions we are most frequently asked.

Can you provide us with a specification for intumescent coating of structural steel?

Yes. We can provide a full coating specification which can be included in your project documentation.

We have a design where structural steel to be fire rated is located in partition walls. Can this be done?

Yes. We can provide information regarding the process which addresses this issue.

Are you able to advise us in regards to the selection of steel which is suitable to achieve the required FRL?

Yes. We are able to provide information that will optimize the selection of the steel members to achieve the designated FRL. We can liaise with the project engineer to obtain important information on load ratios and steel critical temperatures that will assist in the accurate determination of the correct steel sizes.

Can you provide verification of compliance to the Australian Standards for your intumescent products?

Yes. Nullifire intumescent basecoats are assessed in accordance with Australian Standards AS1530.4-2005 and AS4100-1998. Relevant documentation can be supplied on request directly to engineers and certifiers.

Can any top coat be applied over Nullifire SC902?

No, only approved top coats may be applied over Nullifire SC902 Intumescent. Please check the approved top coats list for compatibility or alternatively contact Permax.

Can intumescent coatings be used for external steel?

Only intumescent coatings tested and approved for external (exposed to weather) use are suitable. Water based intumescent coatings are not suitable for external applications, even if coated with a top seal. They are formulated only for use in fully protected dry, internal locations.

Nullifire SC902 ‘hybrid’ intumescent coating is tested and approved for application to external steel.

What do the intumescent coatings cost in comparison to Vermiculite?

Intumescent coatings are not costed by a sq mtr rate. The thickness of the coating relates to the size of the steel members to be fire rated and the designated FRL (fire rating limit). The heavier the steel, the less coating thickness required to achieve the FRL.

If the steel to be fire rated is concealed from view, is located internally only and there is no urgency for the construction time frame then Vermiculite will be less expensive in pure application cost than intumescent for a 2 hr FRL.

Nullifire SC902 ‘hybrid’ intumescent coating is 60% faster than any other spray applied fire protection system, can be applied off/on-site, is suitable for both internal and external steel and provides up to a 2hr FRL.

Can intumescent coatings be coloured?

No. Most intumescent coatings can have a decorative/protective paint system applied over them which will provide a choice of colours.

Can intumescent coatings be applied with a roller or brush?

Generally, no. Intumescent coatings are very thick (72% Volume Solids or higher) and are applied using airless spray equipment to achieve an acceptable level of finish. This also allows for accurate measurement of applied film thicknesses. Small areas that are not an architectural level finish may be touched up by brush.

Can intumescent coatings be applied off-site?

Water based intumescent coatings are formulated for application on-site as they are more susceptible to damage from transport/handling. Also, off-site coating facilities would be tied up for a considerable amount of time as the water based intumescent coatings, depending on the film thickness required, may need to be sprayed in multiple applications over a number of days and would need extended drying in good weather conditions to cure correctly.

Most solvent based intumescent coatings can only be applied off-site due to their high VOC levels.

Nullifire SC902’hybrid’ intumescent coating is formulated for application both off-site and on-site, it is a ‘fast track’ rapid curing, high build single coat application, Low VOC, primer less system.

We are using small diameter structural steel in our design. Can we achieve a 2 hr FRL?

This will depend to a great degree on what load the steel is supporting. Our engineering staff can provide advice as to how to address this issue.

What Fire Resistance Level (FRL) can Nullifire SC902 achieve?

Nullifire SC902 can achieve an FRL of up to 120 minutes. This will depend on the mass of the steel member/s to be coated and the load the member/s are supporting. Please use the Permax calculator to check if a member can achieve the required FRL and contact Permax to assist you.

Can we achieve 120/120/120 by using Nullifire product?

The three numbers represent the FRL for the structural adequacy (load), integrity (flames, gas, smokes) and insulation (temperature). Generally, intumescent paint for structural steel can only achieve the fire protection for the structural adequacy. An intumescent coated steel member could not prevent the smokes movement and temperature rise of an area. Therefore Nullifire intumescent paint can only achieve 120/-/- (or 90/-/- & 60/-/-) for structural steel.

What is HP/A, ksm, steel section factor, and how is it relevant to passive fire protection?

HP/A, ksm, or also known as the steel section factor is the heated perimeter to cross sectional area ratio of steel members. HP/A gives an indication of the heating rate and governs selection of steel sections that can achieve the required FRL. Generally, a larger, thicker steel member will have a lower HP/A and thus have a lower heating rate than a smaller, thinner steel member. This is important to consider because members with high HP/A will require more passive fire protection than members with low HP/A.

Why is the standard critical steel temperature 550, 620 and 700 degrees C?

The standard critical steel temperature reflects a conservative estimate of loads based on the most common loading scenarios. For floor loads, we assume columns are the most heavily loaded elements, requiring a load ratio of 0.51, beams require a load ratio of 0.4 and members supporting a roof load requiring a load ratio of 0.3.

What is the standard structural loading used in a fire case?

The standard structural loading used in a fire case can be found in AS1170.1. It is different from a standard structural loading.

For example, a standard limit state loading for beams is 1.25G + 1.5Q, where G is the designed dead load, and Q is the designed live load. In a fire case, the standard loading for beams is G+0.4Q.

How are rf (load ratios) calculated, and what limiting steel temperature should I use?

Rf load ratios are calculated based on the member capacity at room temperature and the designed member capacity in a fire environment. The load ratio determines the limiting steel temperature based on equation 12.5 of AS4100.1998 – Section 12:

Tl = 905 – 690rf where Tl is the limiting steel temperature.

For example, a 460UB67.1 beam with 399kNm design flexural strength capacity at room temperature and 130kNm design bending moment in a fire environment will have a load ratio of approximately Rf = 0.33

What is Core-Filling?

Core-filling is the process of adding a grout or concrete mixture of 40MPa or less to a hollow structural steel section to create a composite column. The purpose of core-filling is to reduce the section factor of the structural steel, allowing it to achieve a higher FRL rating with a thinner coat of intumescent. Core-filling achieves this by increasing the thermal insulation property and structural compressive capacity of the composite section.

Is Core-Filling possible for small hollow section sizes, (i.e. 75X75 SHS, 114.3 CHS)?

Yes, Core-filling is possible even for small structural hollow section sizes as low as 75X75X3 SHS and 114.3X3 CHS.

How are connections fire-rated?

Connections are usually fire-rated to the same dry film thickness of the primary member directly attached. Connections are usually masked during off-site spraying, and are sprayed on-site after the steel is erected.

Can the primary steel be penetrated? If so what are the details?

Permax strongly recommend that any primary steel should not be penetrated. However, in some cases, it is possible to use low diameter studs to penetrate protected steelwork in order to support light metal framing, light panels, window fixings etc. It is important to consult the Permax team if you are planning on penetrating any structural steel elements.

What is the minimal gap for intumescent expansion?

The minimal gap for intumescent expansion is 30mm. This is the approximate distance for a thin layer of intumescent to activate before light weight elements such as plasterboards and unprotected members begin to fail and fall off, allowing the rest of the intumescent to char and expand.

Can metal stud framing be fixed directly to protected structural steel?

Metal stud framing and light weight elements can be directly fixed to structural steel. The main condition is the frame itself must be coated with intumescent using the same dry film thickness as the primary structural steel member. Please refer to Nullifire Australia Technical Advisory Note: Metal Stud Frame for more details.

Can plasterboards be positioned hard up against the protected steel? What are the limitations?

Indicative tests indicated that plasterboard encasement does not degrade fire performance of intumescent protected steel but rather, improved it. We can use the standard product loading tables for Nullifire SC902 with encased sections for both columns and beams. The only condition being that the plasterboard cannot be mechanically fixed directly to the protected steelwork. Please refer to Nullifire Australia Technical Advisory Note: Plasterboard Proximity for more details.

What is Coat-back and where is it used?

Coat-back is a process of coating an area beyond the specified protected structural steel member. It is mainly used when an intermediate zone between protected structural steel and unprotected steel, other substrates or other passive fire protection systems.

Can any primer be applied before Nullifire SC902?

No, only approved primers may be applied prior to Nullifire SC902 being coated. Please check the approved primers list for compatibility or alternatively contact Permax.

How can I get a price for intumescent fire protection?

There are approved applicators and distributers of the Nullifire intumescent system Australia wide who would be happy to assist with a quote. Please contact the Permax team for further information.

Can any top coat be applied over Nullifire SC902?

No, only approved top coats may be applied over Nullifire SC902 Intumescent. Please check the approved top coats list for compatibility or alternatively contact Permax.

Can anyone apply the product?

No, you need to be an approved applicator with proper training with the intumescent and equipment in order to apply the product. Please contact the Nullifire Australia team for further information.

What does the product cost per m2

The thickness of an intumescent coating is calculated based on the FRL, steel geometry and weight as well as what type of load it is supporting. It is therefore impossible to provide a m2 rate as it is different for every member.

Can the intumescent be applied on galvanised steel?

For the Nullifire SC902 intumescent system the steel substrate requires a light whip blast over the galvanisation before the intumescent is applied.

Does the intumescent system need a primer?

Water based intumescent systems do require a primer.

The Nullifire SC902 system is self priming and does not need a primer in order to adhere to the steel substrate. Therefore a primer is not required for internal applications. For external steel a primer should be applied for durability.

How is the product applied?

Intumescent systems are applied using airless spray equipment however small areas can usually be patched up using the Nullifire intumescent system.

How many application coats does the product require?

A water-based intumescent system is applied in 600 micron coating thicknesses intil the desired dry film thickness is reached.

The Nullifire SC902 hybrid intumescent system can apply up to 6mm in one coat if required.

Who provides the certification for the fire protection?

Depending on the State in which the project is carried out the approved applicator/subcontractor would supply a certificate of completion in NSW or Form 16 in Queensland

Can we achieve 120/120/120 in using a Nullifire product?

The three numbers represent the FRL for the structural adequacy (load), integrity (flames, gas, smokes) and insulation (temperature). Generally, intumescent paint for structural steel can only achieve the fire protection for the structural adequacy. An intumescent coated steel member could not prevent the smokes movement and temperature rise of an area. Therefore Nullifire intumescent paint can only achieve 120/-/- (or 90/-/- & 60/-/-) for structural steel.

Is there a warranty for the product?

Permax can provide a warranty for the intumescent paint system applied on your project. A warranty must be requested prior to the start of any project.

What is the benefit of Core-Filling in fire protection field?

Core-Filling reduces the required thickness of intumescent coating by reducing the effective section factor Hp/A, which therefore, reduces the fire protection coatings cost.

When should we consider Core-Filling?

The Core-Filling procedure is commonly used for structural steel columns to increase the mass for hollow sections. The injected concrete could help with the fire resistance for steel. It is essrntial that consideration is given to ensure that Core-Filling meets with the required Fire Resistant Level when the thickness of the section is too thin.

Which intumescent product should I be using?

Nullifire products are designed to excel in different circumstances, so selecting the right one for your project requirements is essential. To make it easy, we have developed a guide listing the things you should consider when choosing a fire-rated intumescent

Does Nullifire SC902 have to be applied on-site or off-site?

The answer is both and neither. Nullifire SC902 is a Low VOC (Volatile Organic Compounds) intumescent, allowing it to be applied on-site. However, because Nullifire SC902 is also a very durable intumescent system, it can be applied off-site and transported to site for erection. Once the steel is erected, all the connections must be coated in Nullifire SC902.

Which intumescent product should I be using?

Nullifire products are designed to excel in different circumstances, so selecting the right one for your project requirements is essential. To make it easy, we have developed a guide listing the things you should consider when choosing a fire-rated intumescent

What Fire Resistance Level (FRL) can Nullifire SC902 achieve?

Nullifire SC902 can achieve an FRL of up to 120 minutes. This will depend on the mass of the steel member/s to be coated and the load the member/s are supporting. Please use the Permax calculator to check if a member can achieve the required FRL and contact Permax to assist you.

Can we apply Nullifire SC902 onto galvanised steel?

Yes, but it will need to be sand blasted the galvanised steel to SA1 (internal environment) or SA2.5 (external environment) as per AS1627.4 Metal finishing – Preparation and pretreatment of surfaces – Abrasive blast cleaning of steel.

Can anyone buy a drum of product from Permax?

Nullifire SC902 is an engineered fire protection solution which can only be applied by an approved applicator who has received certified training with the product. If applied without training product warranties may be voided. If you are interested becoming a qualified trainer please do not hesitate to contact us

Can any primer be applied before Nullifire SC902?

No, only approved primers may be applied prior to Nullifire SC902 being coated. Please check the approved primers list for compatibility or alternatively contact Permax.

When should we consider Core-Filling?

The Core-Filling procedure is commonly used for structural steel columns to increase the mass for hollow sections. The injected concrete could help with the fire resistance for steel. It is essrntial that consideration is given to ensure that Core-Filling meets with the required Fire Resistant Level when the thickness of the section is too thin.

How many coats of application does SC902 require?

SC902 is very unique and offers amazing labour-related time savings because it can be applied in 1 coat to achieve an FRL of 120 minutes. The application process maybe split into two coats if a commercial or architectural level of finish is required.

Key projects

Nullifire products have been proudly used as the intumescent of choice on a number of recent constructions including:

5 Martin Place SYDNEY Old Commonwealth Bank Building ‘The Money Box’

Nullifire SC902 “Fast Track’ Hybrid intumescent basecoat was sele...

Brisbane International Airport - Air New Zealand lounge

Brisbane International Airport is mid-way through planned upgrade works. Perm...

Carrara Gardens Golf & Tennis Academy - Gold Coast

Nullifire SC902 was selected for this project for its proven track record of ...

Melbourne Airport - Terminal 4

The recently opened Southern Precinct of Melbourne Airport Terminal 4 and Pie...