First case of illness [incident]
The first case of illness among NCC’s subcontractors. It was later linked to the other cases and only then reported as an incident.
Additional case of illness [incident]
SSAB is informed of an additional case of illness. Work is paused and relocated to another area. Material previously used as ground fill is replaced. Measurements are initiated with no abnormal results.
Additional symptoms reported [incident]
Additional symptoms are reported from the new location. All work under NCC is paused.
Elevated gas levels
Measurements related to previously halted work are carried out, focusing on gas concentrations in ambient air and inside the cab of a tracked tractor used for excavation work.
Measured gas concentrations in the air, taken when no excavation work was ongoing, were well below the Swedish Work Environment Authority’s applicable limit values for hydrogen sulfide, carbon monoxide, nitrogen dioxide, and sulfur dioxide.
Inside the tracked tractor cab, elevated levels of nitrogen dioxide and sulfur dioxide were recorded during work, exceeding the Swedish Work Environment Authority’s limit values. Measured levels of hydrogen sulfide and carbon monoxide were below applicable limit values. During cab measurements while work was ongoing, operators were wearing powered air‑purifying respirators.
Additional symptoms and construction site closure [incident]
Symptoms are reported from another location involving different work activities. These individuals work for the contractor Keller. All work across the entire construction site is paused and remains suspended.
Expanded measurements
Based on the most recent test results, sampling and measurements are expanded. When SSAB previously received information about symptoms or cases of illness, measurements of soil and air were carried out, without elevated values being identified at that time.
The expansion of measurements means that both the number of measurement points and the personnel resources for testing and analysis have been increased. The purpose is to obtain results that may explain the symptoms previously reported.
Air measurements at the construction site have continued without any machinery in operation. No abnormal values have been recorded.
SSAB continuously measures emissions from existing facilities in Luleå, and these remain within permitted levels.
Information regarding preliminary investigation and continued testing without abnormal values
During the afternoon, SSAB becomes aware through media reports that the police are investigating a suspected work environment offense related to the illness cases at the construction site for SSAB’s new steel mill in Luleå.
Work at the construction site remains paused and will only be resumed when it can be done safely.
During the Easter weekend, air measurements at the construction site continued without any machinery in operation. No abnormal values were recorded.
Continued measurements without abnormal values
On 9 April, the Swedish Work Environment Authority conducts a planned inspection of the construction site for SSAB’s new steel mill in Luleå. The inspection is carried out as part of the Authority’s supervisory mandate.
The inspection aims at fact‑finding and dialogue. We welcome the inspection and view it as an important part of the work to ensure a safe and secure working environment. SSAB supports the Swedish Work Environment Authority in its continued work.
In summary, all measured gases—H₂S (hydrogen sulfide), CO (carbon monoxide), NO₂ (nitrogen dioxide), and SO₂ (sulfur dioxide)—have on average remained below the Swedish Work Environment Authority’s limit values for 8‑hour time‑weighted averages, which define the average exposure permitted during a workday, or rolling 15‑minute averages, which define the maximum concentration permitted over shorter periods. No measured values have exceeded applicable limit values.
Measurements were conducted both in ambient air and with work vehicles’ engines switched off and at idle. No construction work or mechanical activities were carried out during this time, and no operators were permanently present in the machine cab during the measurements conducted there.
Based on measurement results up to and including 9 April, there are no indications that air quality deviates from what can normally be expected in the area or that it would pose any clear risk.
Continued measurements without abnormal values
Measurements at the construction site for SSAB’s new steel mill in Luleå continue, with no abnormal results identified. A new update will be provided on Monday, 13 April.
Continued measurements without abnormal values
Previously expanded measurements continue, with no abnormal results identified since the last update.
Activity‑specific measurement program
Since all work at the construction site was paused on 3 April 2026, continuous measurements of airborne gases have been carried out across the entire area (with no ongoing work). The gases measured are hydrogen sulfide (H₂S), nitrogen dioxide (NO₂), carbon monoxide (CO), and sulfur dioxide (SO₂).
The results show no abnormal values at any of the monitored locations.
SSAB plans to carry out a controlled, activity‑specific measurement program involving construction machinery, with the purpose of assessing the working environment in and around machine cabs.
The initially approved activities include idle tests without operators in the cabs, using two pairs of machines. These measurements will be initiated on Wednesday, 15 April.
Information on previous incident [incident]
SSAB receives information from the contractor Nåiden regarding an incident that occurred on 17 March during work at the new pump station for the coke plant. The incident description states that one person is suspected of having been exposed to soil contamination in connection with the work. Nåiden will report the incident to the Swedish Work Environment Authority. SSAB will also notify the Authority. The incident was reported to SSAB with significant delay.
The work was carried out within the area that was reported to the County Administrative Board on 27 June 2025: “Excavation within a contaminated area in connection with the construction of a new pump station at the coke plant, SSAB Luleå.” The subcontractor Nåiden is contracted to perform excavation work in, among other areas, this location, where remediation or mitigation plans have been developed and implemented following notification and in accordance with decisions by the supervisory authority.
The previously reported illness symptoms have not been linked to areas with soil contamination levels exceeding applicable limit values.
Measurement results without abnormal values
On 15 April, SSAB expanded ongoing measurements with an activity‑specific measurement program. As of 16 April, no abnormal values have been identified.
Continued measurements without abnormal values
Measurements continued during the day, and no abnormal values were reported on 17 April either.
Work stoppage at the construction site
SSAB is informed by NCC that SEKO has imposed a work stoppage at the construction site. Safety is our highest and foremost priority. When the work stoppage was imposed, the site had already been closed since 3 April following a decision by SSAB as a safety measure. At present, we cannot state with certainty the root cause of the reported illness cases. Sampling and testing continue in order to confirm or rule out possible causes, so that the site can be reopened safely. As of 20 April, no abnormal values have been recorded.
Additional illness symptoms and gas measurements
On the evening of 20 April, NCC submitted a notification to the Swedish Work Environment Authority regarding confirmed illness symptoms among office staff in NCC’s temporary office facilities at the construction site for the new steel mill. NCC has informed SSAB that three office employees have exhibited symptoms.
During the Easter weekend, gas measurements were carried out in the ambient air adjacent to all temporary office facilities at the construction site, including SSAB’s temporary offices. No elevated levels of measured gases were recorded in the ambient air.
By measuring the presence of gases in the ambient air, it could also be concluded that it is unlikely that the same gases would be present at different concentrations inside the buildings.
In connection with reporting the symptoms to the Swedish Work Environment Authority, NCC has also informed SSAB of its intention to relocate its office staff to other premises.
Resumption of activity‑specific measurement program
Following constructive dialogue between Keller, the contractor carrying out groundworks at the construction site, and SEKO, the planned test program was resumed today, 23 April, at Aronstorp, a separate work area.
The program concerns measurements under basic operational conditions with an operator in the cab. Measurements are carried out both inside the cab and in the surrounding work environment during normal operation.
The measurements are conducted with union approval and do not constitute a resumption of construction activities, but rather represent a step in the planned and phased measurement program. The decision is based on the fact that all available measurement data have been collected, analyzed, and jointly assessed. Identified risk factors have been evaluated, and measurements continues on a well‑informed basis, with established protective measures in place.
The continued measurement program is based on a shared situational understanding and close cooperation between the parties involved, with the aim of ensuring both a good working environment and trust in the ongoing process. The test environment is continuously monitored through measurements, personal gas detectors, and clear safety procedures. Personnel use prescribed protective equipment.
Measurement and analysis report submitted to the Swedish Work Environment Authority
SSAB has submitted a formal measurement and analysis report to the Swedish Work Environment Authority showing that the investigated air and gas exposures at the construction site in Luleå did not exceed applicable occupational exposure limit values during the measurement period. At the same time, investigations into the cause of the reported symptoms continue, and work remains paused pending a comprehensive and sufficient decision‑making basis.
A report submitted to the Swedish Work Environment Authority presents the results from the air quality monitoring program conducted at the construction site for SSAB Luleå Mini‑Mill during the period 1 April 2026 to 21 April 2026, with the purpose of assessing occupational exposure at the workplace.
The monitoring program at the site comprised four parallel measurement tracks within the relevant area, including:
Compliance was assessed against AFS 2023:14 (Occupational Exposure Limit Values), applying both the occupational exposure limit (OEL, 8‑hour time‑weighted average) and the short‑term exposure limit (STEL, rolling 15‑minute average).
Based on the measurements performed, workers’ exposure during the reporting period remained below the statutory occupational exposure limits specified in AFS 2023:14.
The measurement report draws no conclusions regarding underlying causes, but solely presents the results from measurements conducted to date under non‑active work conditions, i.e., so‑called static ambient conditions.
The measurement results have been shared with contractors at the Luleå construction site and with the respective trade unions.
The monitoring program will be significantly expanded from May 2026 through the establishment of a fixed gas monitoring network consisting of 20 monitoring stations (15 primary locations with a coverage radius of 250 meters and 5 redundant units), supplemented by additional gas sampling in site offices and machine cabs.
Continued measuring without abnormal values
SSAB has continued dialogue with contractors and relevant trade unions by reviewing measurement data from the site.
Testing has been ongoing and continues. No abnormal results have been identified. A long‑term gas monitoring system has been prepared and will be installed in early May.