Companhia Siderúrgica Nacional S A : 4Q23 and 2023 ESG Release

4Q23 ESG Performance

	ESG RESULTS
ENVIRONMENTAL, SOCIAL AND GOVERNANCE	4Q23

Leadership in ESG issues

In the last quarter of 2023, we updated our materiality matrix, following best market practices. The matrix is an important tool to help deepen our understanding of ESG issues from the perspective of our main stakeholders and to help us make strategic decisions. The main change in our matrix was the inclusion of Human Rights, a topic that is increasingly intrinsic to society and our operations, especially considering our expansion projects.

Also, during this period, we completed another fundamental piece of work for the company's sustainability agenda: the integration of our climate risk matrix with nature risks, aspects that are now brought together in a single risk matrix, following the guidelines of the Taskforce on Nature-Related Financial Disclosure (TNFD) and Taskforce on Climate-Related Financial Disclosure (TCFD).

Due to the new assets acquired in 2022, 2023 was also dedicated to reviewing the decarbonization roadmap for the Cement segment, which now accounts for more than 40% of the CSN Group's absolute CO2 emissions. In the last quarter, we announced our new target of a 23% reduction in the intensity of our emissions by 2030. This target has been submitted to the Science Based Targets initiative (SBTi) and is awaiting approval.

Still within the scope of decarbonization at CSN Mineração, the successful tests with 100% electric off-road trucks culminated in the acquisition of this equipment and the entry of another six pieces of equipment, to be tested in 2024.

We ended the year celebrating our progress in all the world's major ESG ratings. After the Sustainalytics agency placed the CSN group and CSN Mineração among the 10 companies with the lowest ESG risk in the sector globally and S&P Global nominated CSN for the Sustainability Yearbook 2023, in addition to awarding the Industry Mover seal in the steel sector, the Company was also recognized as one of the best industrial groups in the world in terms of environmental management, by achieving a historic score in the CDP (Disclosure Insight Action) Climate Change and Water Security questionnaires, reaching the A- score in both categories, which positions us as one of the global leaders in these agendas, according to the organization's criteria.

The quarter also ratifies the constant evolution in our operational safety performance, closing 2023 with the lowest frequency rate of reportable accidents in the last 10 years, in addition to ZERO fatalities at CSN Mineração for the same period. In terms of diversity, we reached 23% female representation in the CSN Group, bringing us closer to the target of 28% women in the workforce by 2025, double what we had in 2020. These and other highlights, as well as our performance in ESG indicators in the last quarter of 2023, can be found on the following pages of this release.

Enjoy your reading!

Doing well, Doing more, Doing it forever

Helena Brennand Guerra

Health, Safety, Environment and Sustainability Director of the CSN Group

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ENVIRONMENTAL, SOCIAL AND GOVERNANCE

ESG Release 4Q23

Since the first quarter of 2023, CSN has started a new format for disclosing its ESG actions and performance, providing its performance in ESG indicators individually. The new model allows stakeholders to access the main results and indicators every quarter and monitor them faster and more effectively.

This ESG Report already incorporates the performance indicators of the new assets of CSN Cimentos, acquired in 2022; in this sense, some absolute indicators will change significantly compared to the previous period, when these operations had not yet been incorporated.

The information included in this release was selected based on relevance and materiality for the company. Quantitative indicators are presented in comparison with the period that best represents the metric for monitoring them. Thus, some are compared with the same period of the previous year, and others will be with the average of the previous year, ensuring a comparison based on seasonality and periodicity

More detailed historical data on CSN's performance and initiatives, in addition to performance on other ESG goals, can be seen in the 2022 Integrated Report, released in April 2023 (esg.csn.com.br/nossa-empresa/relatorio-integrado-gri). The assurance of ESG indicators occurs annually to close the Integrated Report, therefore, the information contained in the quarterly releases is subject to adjustments resulting from this process.

It is also possible to monitor CSN's ESG performance on our website: esg.csn.com.br

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ESG RESULTS 4Q23

ESG Ratings

External recognition in indexes and ratings demonstrates that the Company is constantly evolving, committed to transparency and reporting of the main ESG actions and indicators, and in line with sustainable development.

The year of 2023 was marked by great achievements, which was positively reflected in the evaluation of internationally recognized ESG ratings. We maintained the excellent ratings achieved in 2022 at the agencies Sustainalytics and S&P Global. The MSCI agency raised CSN's rating from B to BB.

CSN also became recognized as one of the best industrial groups in the world in environmental management by CDP (Disclosure Insight Action), achieving excellent results given the evolution of the score from B to A- in Climate Change and, in Water Security, from B- to A- .

2020	2021	2022	2023
50.1	39.1	26,0	26,1
CCC	CCC	B	BB
34	3	55	54
44
D	D+	D+	C-
C	B	B	A-
2	3	3	3
27	30	45	TBD
		2,5	3,4

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ENVIRONMENTAL, SOCIAL AND GOVERNANCE

Awards and Recognition

ESG RESULTS 4Q23

2023

CSN is recognized in the TOP

100 Open Corps ranking

CSN Mineração won the

Transparency Trophy from ANEFAC (National Association of Executives)

CSN Cimentos received the

"Women in Leadership" 2022/23 award from the NGO Women In Leadership In Latin America (WILL), in partnership with Valor Econômico and Editora Globo

CSN Cimentos won the Great

Place to Work Seal

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CSN Araucária receives the Paraná Climate Seal

CSN Group receives Challenge move award

CSN Foundation, through the Garoto

Cidadão Program, receives the Human

Rights and Diversity Seal¹ and the SESI

Seal² ODS 2023

CSN Cimentos receives ABRH Award for best human development initiative

CSN Group receives "Desafio

Mover" award

CSN won General Motors "Supplier of the Year" award

¹Secretaria Municipal de Direitos Humanos e Cidadania de São Paulo

² Serviço Social da Industria

ENVIRONMENTAL, SOCIAL AND GOVERNANCE

Main ESG Goals1

ESG RESULTS 4Q23

ESG Goals

Climate Change

• 20% reduction in CO2e emissions per ton of crude steel by 2035, WSA (World Steel Association) methodology compared to the base year 2018.
• Reduce CO2e emissions per ton of cement by 23% by 2030, reaching 392 kgCO2e/t cement, GCCA (Global Cement and

Natural	Concrete Association) methodology compared to the base year
Capital	2020.	New target submitted to SBTi

• 30% reduction in CO2e emissions per ton of ore produced by 2035 (scopes 1 and 2), base year 2019.
• Carbon neutral by 2044 in scope 1 and 2 emissions by CSN Mineração.

Atmospheric Emissions

• Reduce 40% of particulate matter emissions per ton of crude steel produced at the UPV (steelworks) by 2030, base year 2019.

Water Use Efficiency and Effluent Management

• By 2025, systematize and transparently present the volumes of water permitted, captured and released from CSN Group units, relating them to the risks of water scarcity in the basins in which
  they are located. New target

Management and De-characterization of Dams

• Carry out the complete de-characterization of dams built upstream of CSN by 2030..

ESG Goals

Intelectual Governança, Ética e Compliance

Capital

• Carry out compliance training with 90% of active employees in the CSN Group, covering the code of conduct and anti-corruption policy by 2023.
• Continuously increase our Compliance Index with the best governance practices provided for in CVM Resolution No. 80/2022
  (considered "Practice" and "Partially Practice")

	Health and Workplace Safety
Human
and Social	✓ Continually achieve the zero-fatality rate across the CSN Group
Capital	(own employees and third parties).
	✓ Reduce the accident frequency rate (CAF+SAF - own and third
	parties) by 30% by 2030 in the CSN Group in relation to the base
	year 2020 (factor of 1 million hours worked).
	✓ Reduce by 30% the number of lost days due to accidents involving
	own employees by 2030 , compared to 2021.
	Diversity and Inclusion
	✓ Achieve 28% female representation in the CSN Group by 2025 (base
	year 2020).

1. The Company has other ESG goals that are published in its Integrated Report. Monitoring the performance of all the Company's goals can be carried out annually through this document.

"OUR AMBITION IS TO PROVIDE ESSENTIAL CARBON NEUTRAL MATERIALS TO THE SOCIETY BY 2050."

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ENVIRONMENTAL, SOCIAL AND GOVERNANCE

Perfomance on the main

ESG Goals

	Indicators	Unit	Base-Year	2023	Δ%	Status	Goal	Year-
	Indicator	Goal
	Emission Intensity	tCO2e /	2,1	2,07	-1		1.68	2035
	Steel¹	t crude steel	(2018)
Environmental	Emission Intensity	kgCO2e /	509	485	-6		374	2030
Cement²	t cementitious	(2020)
	Emission Intensity	kgCO2e /	5,7	7,33	28		4.04	2035
	Mining (GHG)³	t ore	(2019)
Social			2,46
	Accident Frequency Rate4	LTI + NonLTI	1,79	-27		1.72	2030
	(2020)
Governance			14,3
	Diversity (women on staff)	%	23	60		28%	2025
	(2020)

1 Considers emissions according to the WSA methodology and the production of UPV and SWT units.

2 Indicator GCCA 62 - Specific gross CO2 per ton of cementitious product (kgCO2e/t cementitious). The target for 2030 was recalculated based on the retroactive inclusion of new assets acquired in 2022 in the base year. Goal submitted to SBTi and awaiting approval.

3 Considers scope 1 and 2 emissions divided per ton of iron ore produced at CSN Mineração, according to the methodology of the Brazilian GHG Protocol Program.

4 The rate considers accidents with and without absence of employees and third parties/1 million hours worked at all the Company's units located in Brazil.

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	ESG RESULTS
ENVIRONMENTAL, SOCIAL AND GOVERNANCE	4Q23

ESG PERFORMANCE

GOVERNANCE

DAM

MANAGEMENT

✓ All CSN Mineração dams audited and considered stable

HEALTH AND SAFETY

• • New materiality matrix
• Evolution of the CDP grade from B to A-

in Climate Change and in Water Security from B- to A-

• • 100% of employees trained in Compliance
• Integration of the climate and nature risks matrix

SOCIAL AND DIVERSITY

• +60% women representative in the CSN Group, compared to 2020 (base year)
• • +20% women representative in leadership positions, compared to 2022
  • • +47% of training hours completed, compared to
    • • 
        2022
      • First Investment Program in Rural Productive Inclusion Actions (PINAPS) in TLSA
      • • Adherence to the Empresa Cidadã Program

(Citizen Company)

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• Lowest Accident Frequency Rate (CAF+ SAF own and third parties) in the last 10 years (1,786)
• • -19%in the number of days lost due to accidents involving own employees
  • • Implementation of Agir Program
    • • 10 years with zero fatalities at CSN Mineração

ENVIRONMENTAL

• • • • -2% in kgCO2e / t cement emissions, compared to 2022
      • -7%in kgCO2e / t iron ore emissions, compared to 2022
    • CSN Cimentos submitted a new goal to the SBTi
  • -30%in particulate matter emissions in the steel industry, compared to 2022
• 96% of waste sent for sustainable treatments, +5% compared to 2022

ENVIRONMENTAL, SOCIAL AND GOVERNANCE

ENVIRONMENTALPERFORMANCE

Atmospheric Emissions - Steel	Unit	2022	2023	Δ%
NOX Emission	t	1.616	2.002	24
SOX Emission	t	2.344	1.878	-20
PM Emission	t	3.867	2.713	-30
Air Quality - Steel	Unit	2022	2023	Air Quality Index
UPV - Vila Santa Cecília - Automatic Station	µg/m³	25,7	20,8	Boa
UPV - Retiro - Automatic Station	µg/m³	45,0	28,4	Boa
UPV - Belmonte - Automatic Station	µg/m³	42,88	35,4	Boa
Atmospheric Emissions² - Cement	Unit	2022	2023	Δ%
NOX Emission	t	5,251.9	11,126.1	112
SOX Emission	t	1,808.7	9,711.5	437
MP Emission	t	459.8	1,381.8	201
Water - CSN	Unit	2022	2023	Δ%
Water withdrawal	Megaliters	92,212	99,106	7
Water disposal	Megaliters	70,458	79,182	12
Water consumption	Megaliters	21,755	19,924	-8
Water Intensity CSN	Unit	2022	2023	Δ%
Intensity per steel production	M³/ t steel	15.5	18.0	16
Intensity per cement production³	L/ t cement	0.07	0.19	171
Intensity per ore production4	M³/ t ore	0.26	0.26	-
Waste CSN3	Unit	2022	2023	Δ%
Hazardous Waste Generated	t	53,308	56,795	7
Non-Hazadous Waste Generated	t	3,625,189	3,565,432	-2
Percentage sent for sustainable treatment	t	92.0	96.3	5
	%
Climate change	Unit	2022	2023	Δ%
Emissions Intensity per Steel Production5	tCO2/t	1.99	2.07	4
Emissions Intensity per Cementitious Production3 e 6	kgCO2/t	497	485	-2
Emissions Intensity per Iron Ore Production7	kgCO2/t	7.92	7.33	-7

1 Considers monitoring carried out at automatic stations and presents the annual average of emissions. Air quality was classified as "good" in more	5 Considers emissions according to the WSA methodology and production of UPV and SWT units
than 90% of measurements.	6 GCCA 62 indicator - Specific gross CO2 per ton of cementitious product (kgCO2e/ton cementitious). 2022 only considers the Arcos
2 The large variation in the values ​​ofAtmospheric Emissions in the Cement segment is due to the entry of seven units acquired in 2022, with	and Volta Redonda units. In 2023, data on CSN Cimentos new assets were included
consolidated results in 2023	7 Considers scope 1 and 2 emissions divided per ton of iron ore produced at CSN Mineração, according to the methodology of the
3 Considers recently acquired Cement units in 2023 data	Brazilian GHG Protocol Program
4 Considers the capture of water from the production process of the central plant of Casa de Pedra, the production process of Pires and drinking water

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ESG RESULTS 4Q23

ENVIRONMENTAL, SOCIAL AND GOVERNANCE

Governance and Transparency Dimension

MAIN ADVANCES

New Materiality Matrix

At the end of 2023, CSN updated its materiality aligned with the biennial periodicity adopted as the best market practice. The methodology used adheres to the organic materiality approach, providing a more dynamic, thorough, and continuous view of stakeholders' expectations and the impacts, risks, and opportunities associated with material topics. The review process also adopted a dual materiality perspective, meeting the requirements outlined by IFRS S1 and GRI standards, with topics analyzed from the perspectives of impact materiality and financial materiality. This update resulted in a subtle change in the company's materiality matrix: the inclusion of the Human Rights theme and the consolidation of the Circular Economy, Water and Effluents, and Atmospheric Emissions themes into an umbrella theme, "Eco-efficiency".

CSN is committed to goals connected to its material themes, guiding the Company towards more efficient, integrated, and sustainable management. Performance on key goals can be verified on page 6 of this document.

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ESG RESULTS 4Q23

	ESG RESULTS
ENVIRONMENTAL, SOCIAL AND GOVERNANCE	4Q23

Governance and Transparency Dimension

MAIN ADVANCES

Climate and Nature-Related

Risks Matrix

In 2023, the identification and prioritization of risks and opportunities related to nature began following the guidelines of the Taskforce on Nature-Related Financial Disclosure (TNFD). This process was conducted in conjunction with previous work on climate risks, aligned with the Taskforce on Climate- Related Financial Disclosure (TCFD) guidelines, already established in the company since 2021.

In this regard, it is worth noting that the mapping and prioritization of climate and nature risks were integrated, thus composing a single matrix aligned with TCFD and TNFD guidelines, finalized in the last quarter of 2023.

Among the main activities for 2024 is the deepening of risk analysis through the Climate Vulnerability study and the formalization of actions to mitigate identified nature risks.

CSN Conecta

In November 2023, the second edition of the CSN Connect Program was concluded. The program aims to identify initiatives with ESG actions that could transform the day-to-day operations of the CSN Group and be accelerated. In this cycle, there were 105 projects submitted, with 14 finalists selected for full implementation and 3 winners awarded. The themes addressed were: water and effluents; energy efficiency; waste management; climate change; diversity and inclusion; biodiversity and forests; and health and safety.

The winning projects were presented during the ESG week, and they are:

• 1º Mining: Mobile Fuel Station on the Mine;
• 2º Cement: Safe Confined Space Inspection;
• 3º Steel: Smart Digital Plugs for Electromotive Tools.

ESG Week

In the 4th quarter of 2023, the 4th edition of the ESG Week took place, a week that includes various activities aimed at engaging our employees in ESG initiatives. In this edition, the event featured a new format, with a mix of online lectures and in-person activities at business units, addressing topics relevant to the reality of each segment and unit within the CSN Group.

The lecture topics included: Tailings Reprocessing in Mining, the Capacitar Program in Steelmaking, Women in Leadership at CSN Cimentos, Renewable Energy, and Inclusive Leadership in the railway and energy sectors. During the week, one day was dedicated to Compliance Day, an annual event that reinforces the importance of compliance, featuring highlights of the year and a specific focus on the importance of Due Diligence and Integrity in supplier relationships.

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