citations per 100 inspection hours
ⓘThis rate is recorded citations divided by MSHA inspection hours, per 100 hours. It reflects inspection effort, not mine size or production.
Rate withheld: 371 inspection hours is too few for a stable rate. A minimum of 1,000 inspection hours is required.
Source: MSHA inspections data, updated weekly.
Niagara Stone has $3K in proposed MSHA penalties and $0 outstanding across 0 contested dockets.
Penalty disposition
ⓘDifferences between proposed and paid penalties reflect both settlements and conference reductions and amounts still owed. Outstanding is the balance currently owed.
$3K
proposed penalties
$3K
current assessed
$3K
paid to date
$0
outstanding
14 assessments are final orders; 0 contested dockets.
As of the most recent assessment on 2026-03-25.
Source: MSHA assessed-violations and conference/litigation data, updated weekly.
Violation severity profile
ⓘShares are computed over citations that carry the MSHA gravity and negligence coding; a small share of records are uncoded.
Source: MSHA violations gravity and negligence coding, updated weekly.
Health sampling
ⓘA sample is a point in time compliance measurement, not an individual exposure history. These figures describe MSHA sampling records and do not establish causation or personal dose.
Metal and nonmetal contaminants (personal samples)
ⓘMany samples are screening measurements of substances with no applicable exposure limit; they are counted as samples but excluded from every over-limit figure. Over-limit shares use only limit-tested samples.
Last sampled: 2025-12-17
0%
of limit-tested samples over the exposure limit
12
samples
5
limit-tested
Most sampled contaminants
Quartz, respirable, >1% Qtz10
Respirable dust, <.1mg2
Show the individual readings (12)
Date
Contaminant
Concentration
Limit
Conc / limit
Occupation
2025-12-17
Quartz, respirable, >1% Qtz
0.14
Forklift Operator
2025-12-17
Respirable dust, <.1mg
0
Stone Polisher/Cutter
2025-12-17
Respirable dust, <.1mg
0
Stone Polisher/Cutter
2021-03-17
Quartz, respirable, >1% Qtz
0.68
1.79
0.38
Forklift Operator
2021-03-17
Quartz, respirable, >1% Qtz
0.54
Stone Polisher/Cutter
2021-03-17
Quartz, respirable, >1% Qtz
0.87
1.89
0.46
Stone Polisher/Cutter
2019-03-06
Quartz, respirable, >1% Qtz
0.49
Cutting Mach Operator
2019-03-06
Quartz, respirable, >1% Qtz
0.26
Forklift Operator
2019-03-06
Quartz, respirable, >1% Qtz
0.23
Cutting Mach Helper
2017-01-11
Quartz, respirable, >1% Qtz
0.42
1.93
0.22
Cutting Mach Helper
2017-01-11
Quartz, respirable, >1% Qtz
0.42
1.74
0.24
Cutting Mach Operator
2017-01-11
Quartz, respirable, >1% Qtz
0.52
1.34
0.39
Forklift Operator
Source: MSHA respirable dust, quartz, and noise sampling records, updated weekly. Metal/nonmetal contaminant figures come from MSHA's Personal Health Samples and Area Samples files (public record), updated weekly.
Niagara Stone recorded 0.00 reportable injury cases per 100 full-time workers in 2025.
Injury rate, 2025
ⓘThis rate is reportable injury cases per 100 full-time-equivalent workers per year, computed as 200,000 times cases divided by MSHA operator-reported employee-hours. Cases are injuries MSHA graded degree 01 through 07; accident-only events that hurt no one are excluded, and so are contractor injuries, whose hours do not attach to a single mine. Rates begin in 2000, when quarterly employment reporting starts, and are withheld below 20,000 hours in a year.
0.00
total case rate
0.00
days-away rate
0.000
fatality rate
No reportable injury cases in any year shown. Employee-hours were reported in each of those years, so these are true zeros rather than missing data. Citations, listed in the compliance record above, are inspector-found violations and are counted separately from worker injuries.
Below average. The US metal and nonmetal mining average was 1.65 and the all-US-mining average was 1.97 cases per 100 workers.
In Wisconsin, metal and nonmetal mining averaged 1.80 cases per 100 workers that year.
Under 100,000 employee-hours were reported that year, so a single case moves the rate by two or more. Read the figure as approximate.
Year
total case rate
days-away
fatal
2025 *
0.00
0.00
0.000
2024 *
0.00
0.00
0.000
2019 *
0.00
0.00
0.000
* Fewer than 100,000 employee-hours that year; the rate is less stable.
Source: injury cases from MSHA accident and injury records; employee-hours from MSHA quarterly employment reports. Rate is cases per 100 full-time-equivalent workers, operator employees only.
Source: MSHA controller and operator history, updated weekly.
Workforce and production
Year
Employees
2026
9
2025
11
2024
11
2023
8
2022
9
2021
8
2020
4
2019
9
2018
9
2017
6
2016
6
2015
6
Source: MSHA quarterly employment and production, updated weekly.
Niagara Stone sits in Fond du Lac County, Wisconsin, where the Census mining category is 0.2% of county employment.
Local economic context
ⓘCounty figures come from the US Census Bureau's American Community Survey, 5-year pooled estimates, so the 2023 vintage covers 2019 through 2023. The Census category is 'mining, quarrying, and oil and gas extraction', which is broader than MSHA jurisdiction and includes oil and gas workers no mine employs. These figures describe the surrounding county, not this mine, and are not a factor in any specific incident.
Fond du Lac County, Wisconsin · Population 104,053
0.2%
Mining share of county employment
$73,154
Median household income
Source: US Census Bureau, American Community Survey 2023 5-year estimates.
Quarterly safety rates
ⓘCitations per million reported employee-hours. Rates begin in 2000, when MSHA's quarterly employment data starts; earlier incidents are counted but cannot be rate-adjusted. Quarters under 100,000 reported hours are greyed: too few hours for a stable rate.
Citations per million employee-hours, as reported to MSHA
Quarter
Hours worked
Citations
S&S
Per 1M hrs
2026 Q2
4,496
0
0
0.0
2026 Q1
8,473
2
0
236.0
2025 Q4
5,843
1
0
171.1
2025 Q3
7,698
0
0
0.0
2025 Q2
7,597
0
0
0.0
2025 Q1
8,133
1
0
123.0
2024 Q4
8,135
0
0
0.0
2024 Q3
7,193
0
0
0.0
Show 37 earlier quartersHide earlier quarters
Quarter
Hours worked
Citations
S&S
Per 1M hrs
2024 Q2
5,497
2
1
363.8
2024 Q1
5,114
1
1
195.5
2023 Q4
4,931
0
0
0.0
2023 Q3
4,979
1
0
200.8
2023 Q2
4,261
0
0
0.0
2023 Q1
4,489
0
0
0.0
2022 Q4
4,897
0
0
0.0
2022 Q3
6,103
0
0
0.0
2022 Q2
4,611
0
0
0.0
2022 Q1
4,386
0
0
0.0
2021 Q4
2,323
0
0
0.0
2021 Q3
2,737
0
0
0.0
2021 Q2
4,038
0
0
0.0
2021 Q1
3,274
4
2
1221.7
2020 Q4
4,710
0
0
0.0
2020 Q3
1,419
0
0
0.0
2020 Q2
1,609
0
0
0.0
2020 Q1
1,374
0
0
0.0
2019 Q4
2,310
1
0
432.9
2019 Q3
5,225
0
0
0.0
2019 Q2
8,241
0
0
0.0
2019 Q1
4,531
0
0
0.0
2018 Q4
4,772
0
0
0.0
2018 Q3
7,156
0
0
0.0
2018 Q2
4,237
0
0
0.0
2018 Q1
2,902
0
0
0.0
2017 Q4
3,237
0
0
0.0
2017 Q3
3,559
0
0
0.0
2017 Q2
3,444
0
0
0.0
2017 Q1
2,071
1
1
482.9
2016 Q4
3,199
0
0
0.0
2016 Q3
3,665
0
0
0.0
2016 Q2
3,395
0
0
0.0
2016 Q1
2,276
0
0
0.0
2015 Q4
3,339
0
0
0.0
2015 Q3
3,239
0
0
0.0
2015 Q2
2,346
1
0
426.3
No fatalities recorded at this mine.
Reportable incidents
4 on file
2023 · 1 incident
April 12, 2023WI · Metal/Non-Metallaborer, blacksmith, bull gang, parts runner, roustabout, pick-up man, pitmanPOWERED HAULAGE
Miner was picking up a piece of stone from a conveyor belt when a large piece of stone fell onto miner's right hand.
June 29, 2022WI · Metal/Non-Metallaborer, blacksmith, bull gang, parts runner, roustabout, pick-up man, pitmanHANDLING OF MATERIALS
Eden Stone Co., LLC · Caught in, under or between a moving and a stationary object
Miner picked up a piece of stone from the conveyor belt of a stone splitting machine. EE turned to place the stone on a steel table and smashed EE's finger between the table and the stone.
March 10, 2022WI · Metal/Non-Metalbulldozer operator, universal operator, heavy equipment operator, operating engineerPOWERED HAULAGE
The miner was driving a loader with the bucket very close to the ground. The bucket hit a stone and stopped abruptly. Although EE was wearing seatbelt, EE's upper body lurched forward and EE's head struck a switch on the ROPS pillar. EE was cut above right eye and required stitches.