ANNUAL SUMMARY REPORT ON MOLTEN METAL INCIDENTS FOR 2017

October 2018

For the year 2017, 181 reports were received on incidents occurring world-wide compared to

195 reports received for 2016 and 174 reports for 2015. The attached figures summarize the

reports for 2017 as well as the data for the years 1980 thru 2017.

SUMMARY POINTS:

For 2017, there were 181 explosion incidents reported, which is the second highest

number of incidents ever reported in a calendar year and very close to the record year

of 2016 with 195 reports.

There were 157 Force 1 explosions, 24 Force 2 explosions and zero Force 3 explosion

reported in 2017. The 24 Force 2 incidents was the highest amount over the past 10

years.

Although 2017 had the second highest number of reported incidents, there were only 8

minor injuries reported and no serious injuries or fatalities reported. This is the lowest

number of injuries ever reported since the Aluminum Association starting collecting

incident data from 1981! There are probably a number of reasons for this record

number of low injuries in 2017, even with a very high incident rate, but contributors

likely include 1) the increased use of primary and secondary PPE 2) improvements in

PPE materials and design, and 3) an increased focus on hands-free casting operations

that remove personnel from high risk casting operations.

There have been no fatalities reported in the last three years and only 2 over the past 9

years, which is well below the average of 2.5 fatalities per year reported from 1981 thru

2017.

It should be noted that although reports are received globally, there were news and

media reports in 2017 of serious molten metal explosions with possible fatalities that

occurred outside of North America, however despite the Aluminum Association’s

efforts to obtain reports, no reports were received on these incidents and they are

therefore not reflected in the data.

The trend of a reduced number of Force 3 incidents over the past 10 years has continued

in 2017. For both the past 10 years and past 5 years the average number of Force 3

explosions per year is only 0.6 Force 3 incidents / yr. This is compared to an average of

3.1 Force 3 explosions per year for the entire length of the program, 1981 through 2017.

A notable downward trend of Force 2 explosions observed from 2006 through 2014 was

reversed in 2016 with a jump to 18 Force 2 explosions and continued into 2017 with 24

Force 2 incidents.

As is typical of previous years, in 2017 the highest number of incidents were reported

in Reduction process plants – 84 incidents with 6 injuries of the 8 total minor injuries.

Most explosions occurred in the casting area as typical in the past; 64 Force 1 and 11

Force 2. Reported melting incidents was close to this, with 60 Force 1 and 8 Force 2.

Historically there have been more Melting incidents than in any other process category,

but this trend has been reversed in recent years with more Casting explosions than

Melting explosions. Currently the total number of Casting and Melting incidents are

about equal for the entire reporting period beginning in the early 1980’s.

For the years 1981 thru 2017, Force 2 explosions have occurred at an average rate of

22.2/yr., so 2017 was not significantly different from the overall average with 24 Force

2 incidents. However, compared to the past 5- and 10-year averages of 12.8/yr. and 14.6

/ yr. respectively, 2017 was significantly higher.

Most casting explosions occurred at start-up, as has been the norm; 63 of the 68

incidents which had this information provided. All Force 2 casting incidents (11)

occurred during start-up. DC casting and sow / mold casting accounted for 37 incidents

each.

As is typical of past years, most melting explosions occurred due to wet or contaminated

scrap, 49 of the 68 incidents with 5 being Force 2. The second highest reason for melting

explosions was related to tools and drain or skim pans; three of the 8 reports were Force

2.

Most injuries, three of the 8, occurred during transfer operations. Typically, in the past,

most injuries have been in the casting operation.

EXPLANATION & DISCUSSION OF CHARTS AND DATA:

The Aluminum Association classifies molten metal explosions according to Force level, with

Force 1 being the least severe and Force 3 being the most severe. Table 1 below provides

information on the criteria used for rating Force level. Figures 1 through Figure 32 display

various charts and tables as described in the discussion below and are provided after the

discussion.

Table 1:

Explosion Rating Force Criteria

LOW SEVERE

Figure 1 displays by year from 1981 thru 2017 the total number of reported incidents, 3716. The

181 explosions reported in 2017 is the second highest number of incidents reported in a year and

continues the upward trend of explosions reported over the past 6 years. The years from 2000

through 2007 continue to stand out with over 110 explosions reported in each of these eight

years with an average rate of 145 explosions. 2015 thru 2017, however, average even higher, at

183 explosions.

Figures 2 thru 7 provide Force Level data for the years 1981 thru 2017 in various formats,

including the number of incidents and rates. Figure 2 displays the reported incidents each year

for all three Force Levels. In 2017 there were 157 Force 1, 24 Force 2 and 0 Force 3 explosions.

The 24 Force 2 explosions in 2017 is the highest number at this force level over the past 10 years.

Figure 3 shows the data for only Force Levels 2 and 3 and Figure 4 displays only Force Level 3.

Both Figure 3 and Figure 4 include the average number of explosions per year for this time frame.

It is important to note that the average number of Force 3 explosions per year for the last 5 and

10 years is 0.6 / yr., which is well below the average of 3.1 / yr. for the entire reporting history

from 1981 through 2017. A notable downward trend of Force 2 explosions observed in Figure 5

from 2006 through 2014 was reversed in 2016 with a jump to 18 Force 2 explosions and

continued into 2017 with 24 Force 2 incidents.

Figures 6 and 7 display a comparison of all three Force Levels for the entire reporting history

from 1981 through 2017 in two different formats: 1) bar graph and 2) pie chart. Force 1 incidents

account for 74.7% of all incidents, while Force 2 incidents account for 22.2% of the total

compared to 3.1% for Force 3.

Guidelines Force 1 Force 2 Force 3

Property Damage None Minor Considerable

Light Minimal Flash Intense

Sound Short cracking Loud Report Painful

Vibration Short and sharp Brief rolling Massive structural

Metal Dispersion <15 feet >15 to 50 feet >50 feet

Figures 8 thru 12 provide in various formats injury incident data (Minor, Serious and Fatal) for

the years 1981 thru 2017. The Figure 8 bar chart shows Minor, Serious and Fatal injuries for each

year. There was a total of only 8 injuries reported in 2017, all Minor. There have been no

Fatalities reported in the last three years and only 2 over the past 9 years. Also, the 8 injuries

reported in 2017 was the lowest total for any year since the reporting program started in the

early 1980’s. The 18 injuries reported in 2016 is the second lowest number ever reported. The

previous 5 years (2011 - 2015), averaged 33.6 injuries per year.

Figure 9 shows the total injuries in each of these categories from 1981 through 2017. From the

Figure 10 pie chart, 70.0% of all injuries are Minor, with 24.2% being Serious and 5.8% being

Fatal. The % of minor injuries continues to increase compared to the Serious and Fatal injuries.

Figure 11 looks at the % of injuries for each injury category per the total number of reported

incidents. This indicates that for each 100 incidents reported there is a 29% rate for Minor

injuries, a 10% rate for Serious injuries and a 2.5% rate of a Fatality. Since explosions are typically

more likely to be reported when there is an injury of some degree, these numbers are certainly

inflated compared to the situation if all explosions were reported, but this does provide an

indication of the potential rate of an injury per incident.

Figure 12 displays data only related to Fatalities. As indicated above there were no Fatalities

reported in 2015, 2016 and 2017. There have been only two fatalities reported over the past 9

years, which is well below the average of 2.5 fatalities per year reported from 1981 thru 2017.

It should be noted that although reports are received globally, there were news and media

reports in 2017 of serious molten metal explosions with possible fatalities that occurred outside

of North America, however despite the Aluminum Association’s efforts to obtain reports, no

reports were received on these incidents and they are therefore not reflected in the data.

Figures 13 thru 32 provide more detailed information regarding the 181 reported explosions in

2017 along with similar charts comparing this yearly data with the entire database from 1980

thru 2017.

Figure 13 shows the 2017 data by Force Level for each of the four major categories of operations:

Melting, Casting, Transfer and Other. This can be compared to the same data for the years 1980

thru 2017 in Figure 14. In 2017, most explosions occurred in Casting (75), compared to Melting

(68), Transfer (23) and Other (15). All Other explosions occurred in the Reduction Process.

Historically there have been more Melting incidents than in any other process category, but this

trend has been reversed in recent years with more Casting explosions and currently the total

number of Casting and Melting incidents are about equal for the entire reporting period

beginning in the 1980’s.

In the past, there has typically been a higher percentage of Force 2 and Force 3 explosions in

Melting compared to all the other process categories, but this was somewhat different in 2017

with 11 Force 2 explosions in Casting, compared to 8 Force 2 explosions in Melting. In the Other

category, which was all Reduction in 2017, there were 14 Force 1 explosions and 1 Force 2

explosion. The majority of Force 3 explosions for the entire reporting period continues to be

related to the Melting operation with 80 Force 3 explosions, compared to 19 Casting, 9 Transfer

and 8 0ther.

Figure 15 provides 2017 data regarding the type of charge materials involved in 68 Melting

incidents. As in the past, wet or contaminated scrap was the leading cause of Melting explosions,

with 44 Force 1 and 5 Force 2 incidents in this category. This included 6 incidents involving air

bag cannisters, which is now part of recycled automotive scrap that has increased over the past

10-15 years. There were also 2 incidents each of sows on the furnace sill falling into the melt and

excessive charge melting prior to the next charge being loaded into the furnace. Wet / oxidized

Mg and other alloy materials accounted for 6 Force 1 incidents. Wet / rusty tools and drain or

skim pans were also noted as reasons for Melting explosions accounting for 5 Force 1 and 3 Force

2 explosions.

Figure 16 provides a compilation of the Melting explosion data over the years 1980 thru 2017 for

the various types of charging material involved. Wet or contaminated scrap continues to be the

reason for most of the Melting explosions. The second highest area is related to alloying. The

majority of Force 2 and Force 3 Melting explosions have been related to Scrap charging.

Figure 17 provides a breakdown of the 75 Casting incidents in 2017 in two different ways: by

stage in the process and by type of casting process. As mentioned above, Casting had the highest

number of explosions in 2017. There were 11 Force 2 explosions and 0 Force 3 explosion in 2017.

There were 7 of the 75 reports that did not include the cast-stage in the report. As typical for

Casting incidents, 63 of 68 incidents occurred during the Start-up phase. All 11 of the Force 2

incidents occurred during Start-up and 52 Force 1 explosions also occurred during Start-up. Both

DC Slab or Billet and Sow or mold casting each had 37 incidents, accounting for all but one of the

explosions.

For comparison, Figure 18 shows Casting incidents by drop segment for years 1980 - 2017. The

historical data is similar to the 2017 data in that most explosions occur during Start-up, followed

by Steady-state and then Termination. Figure 19 provides the major causes of the 75 casting

incidents in 2017. They are listed by cast stage for DC casting and also for mold or sow casting.

For DC casting, the main Start-up issues were related to wet starting blocks, butt curl control,

hang-ups and metal control to mold failures. The main sow and mold casting incidents were due

to wet or cracked molds, maintenance, the SOP un-adapted or not respected and wet tools.

There were 23 Transfer explosions in 2017 as shown in Figure 13, 4 of these were Force 2. Figure

20 indicates 9 of these explosions were related to wet equipment and 8 were due to wet or rusty

skim or drain pans. More specifically, the four Force 2 explosions were related to: 1) water leaking

into a trough or launder; 2) wet floor; 3) wet crucible and 4) wet or rusty drain pan. Figure 21

provides a bar chart showing the equipment involved in 758 Transfer explosions for the years

1980 thru 2017. Drain pan explosions have the highest frequency overall, same as in 2016.

Figure 22 shows the Injuries by Operation in 2017, resulting from the 181 explosions. There were

only 8 Injuries reported in 2017, compared to 18 Injuries in 2016 and 57 Injuries in 2015. All

injuries were Minor; no Serious injuries or Fatalities reported. Most of the injuries occurred

during Transfer, 3 of the 8. There were 2 each in Melting and Other (Reduction) and 1 in Casting.

The 8 Injuries reported in 2017 was the lowest number of injuries ever reported since the

Aluminum Association started collecting incident data from 1981! There are probably a number

of reasons for this record number of low injuries in 2017, even with a very high incident rate, but

contributors likely include 1) the increased use of primary and secondary PPE 2) improvements

in PPE materials and design, and 3) an increased focus on hands-free casting operations that

remove personnel from high risk casting operations.

Figure 23 provides Injury by Operation data for 1980 thru 2017. The highest number of Minor

and Serious injuries has occurred in the Casting Operation. The Melting Operation accounts for

the highest number of Fatalities, also the highest number of Force 3 explosions as seen in Figure

14. It should be noted that a significant number of injuries have occurred in Transfer Operations,

with 7 Fatalities occurring even from this typically rather straight forward procedure and the

majority of injuries in 2017, three of 8, occurred during metal Transfer.

Figures 24 and 25 provide incident data vs. the type of Process Plant (Reduction, Extrusion,

Rolling and Recycling) for 2017 and for 1980 thru 2017 respectively. In 2017, more than half (84

of the 181 explosion incidents) were reported by Reduction facilities. Rolling and Recycling had

similar numbers, with 44 and 42 respectively. Rolling had the highest number of Force 2

incidents, 10, while Reduction was next with 7. As shown in Figure 25, a majority of the explosions

reported from 1980 thru 2017 occurred in Reduction facilities; the second highest were reported

from Rolling facilities.

The main causes of the 2017 Reduction facility explosions are broken down in Figures 26 and 27.

They are listed by Melting, Casting and Transfer / Reduction incidents. Melting incidents were

related to wet charges and wet tools. The primary reason in the Casting was cracked or wet

molds. Wet equipment, wet sample mold or equipment and wet or rusty drain pans were the

major categories under Transfer and Reduction incidents.

Figure 28 is a bar chart providing 2017 injury information for the 5 minor injuries occurring in

Reduction plants. The two Transfer injuries were the result of wet drain pan and wet crucible.

The Other injuries were given as wet anode and no reason. And the Melting injury was the result

of a wet stirring tool.

The two 2017 Rolling plant Minor Injuries are shown in Figure 29; one was in Casting and the

other in Transfer operations. There were no 2017 injuries in Extrusion operations as shown in

Figure 30.

Figure 31 summarizes the 2017 injury data by type of Process Plant and Figure 32 shows this

same data for 1980 thru 2017.

The last page of the report after the Figures provides an Aluminum Association Molten Metal

Incident Report Form or you can link to the form at:

https://www.aluminum.org/resources/electrical-faqs-and-handbooks/safety

RTR – October 29, 2018

ALUMINUM ASSOCIATION

MOLTEN METAL INCIDENT REPORT

Date of Incident: Predominant Plant Activity: SELECT ONE:

(month/year)

Explosion Force – Mark One: Force 1 Characterization: Force 2 Characterization: Force 3 Characterization: For definition of force, click arrow to see a description

Alloy Metal Temperature °F °C Approximate Amount of Metal Involved lbs kilograms

OPERATION:

Charging / Melting Type of Furnace SELECT ONE:

Furnace Capacity lbs mt % Full

Materials Charged

Outside Storage? Yes No Preheat? Yes No Preheat Time/Temp: hrs °F °C

Transfer Type SELECT ONE:

Casting Type SELECT ONE: Type of Product being Cast:

SELECT ONE:

Stage of Operation: SELECT ONE:

Other Describe

Number of Injuries by Type: Minor Severe Fatal

Provide a brief description of the incident and its root cause(s):

.

_________________________________________________________________________________________________________

_________________________________________________________________________________________________________

_________________________________________________________________________________________________________

If Charging/Melting Incident, please

select appropriate Primary and

Secondary cause(s):

Other

Other

If Contaminations (other than moisture) was

selected, please specify:

SELECT ONE:

If Transfer Incident, please select

appropriate Primary and Secondary

cause(s):

PRIMARY CAUSE:

SECONDARY CAUSE:

If Casting Incident, please select appropriate

Primary and Secondary cause(s):

PRIMARY CAUSE:

SECONDARY CAUSE:

If Bleed-out/Bleed-over is selected above, describe

reason for Bleed-out or Bleed-Over:

If Explosion due to Bleed-out/Bleed-over was selected

above, where was the location of Explosions:

SELECT ONE:

If Metal Level Control Problem was selected above,

please specify location of problem:

SELECT ONE:

Please return to:

Curt Wells

Director, Regulatory Affairs

The Aluminum Association.

1400 Crystal Drive, Suite 430

Arlington, VA 22202