Molten metal spill....

Molten metal spills are common place in our industry. Our industry works hard in response training when spills occur. The Aluminium Plant Safety Blog has posted incidents where thousands of kilograms of molten aluminium spilled on a factory floor and the result was a mess. On the other hand the APSB has posted incidents where a molten metal spills have resulted in explosions, fires, injuries, fatalities. Here is a recent incident that could have been worse if not for the response training that this company had in place.

A report of a fire at a Fruit Valley neighborhood business early Friday morning turned out to be spill of hot liquid metal.

Vancouver firefighters were called to Pacific Die Casting Corp., in Vancouver, Canada, at 12:40 a.m. on morning during the week of September 28, 2014 for a report of a commercial fire.

While on their way to the call, firefighters upgraded the response to a two-alarm, sending more resources to the business because of the report of heavy smoke and people still inside, said the Lead Deputy Fire Marshal.

That was canceled, however, when crews learned that the smoke was coming from molten aluminum that spilled on the ground after a ceramic vat cracked, the Lead Deputy Fire Marshal said. No injuries were reported. Fire crews assisted at the scene but Lead Deputy Fire Marshal said there was no fire. Damage to the vat was estimated at about $12,000 Euros, the Lead Deputy Fire Marshal said.

The Aluminium Plant Safety Blog congratulates the Pacific Die Casting Company for training their employees to recognize the need to contact local emergency management personnel immediately. Congratulations also should be given to the local fire department who upon arriving did not apply water to the molten metal spill. The APSB has posted incidents where fire fighters unknowingly poured water on fires (molten metal, dust, dross) and an explosion results. The importance of incorporating the local fire department in your plant’s safety training has been repeatedly made by the APSB. The Aluminium Times had an article about the incorporating the local emergency management services in training. 

A “small amount of molten metal” can vary widely depending which type of facility. A foundry may consider a small amount of molten metal to be less than 100 kg. Whereas a primary plant may consider a few tonnes to be a small amount of molten metal. Either way, our industry’s history is littered with incidents involving small and large quantities of molten metal which have either exploded or caused fires. Resulting in injuries and fatalities.

This aluminium plant considered a small molten metal spill in the range of 15-20 tonnes. The “little amount of damage” was damaged caused to some electrical conduit and control boxes under the furnace.  Congratulations to the unnamed plant on acknowledging the seriousness of the issue and containing the hazard. This facility no doubt has an excellent management and safety team that has put forth the importance of safety education.

The question that the Aluminium Plant Safety Blog puts forth to the readers is:

Where does a molten metal spill go to?

Molten aluminium is a liquid, albeit a very hot liquid. Any liquid when spilled will flow to the lowest point (if allowed). In many of our facilities the lowest point is either a casting pit, maintenance pit, or under a furnace. There have been numerous incidents where molten metal flowed to the maintenance pit under a furnace coming into contact with moisture, on bare concrete, steel or stainless steel resulting in a catastrophic explosion. Our industry’s best safety practices are to coat any bare substrates that have the potential of coming into contact with molten metal with an approved safety pit coating. Here is a link to the industry’s standard for safety pit coatings (here).

Unfortunately, there are some facilities that operate under a false safety belief that their current practice of not using an approved safety pit coating is fine. That false belief is rationalized by either the statement “we've never had an explosion”, or simply a lack of knowledge. The APSB has visited too many facilities who claim that they have never had an explosion. But when the APSB questions why there is dried molten metal on the bottom of the roofing (25 meters above the casting pit) the plant personnel have no answer. The facilities that have a lack knowledge are at least welcome to new safety information. Either way, safety pit coatings need to be applied wherever molten aluminium can come into contact with bare concrete, steel, and stainless steel.

The Aluminium Association (US) has been at the forefront of molten metal safety in our industry for decades. Their Casthouse Safety Workshops held biannually cover molten metal safety issues.

The next Casthouse Safety Workshop will be held the week of October 27 in Nashville, Tennessee. More information can be found here in the near future (here).

The Aluminium Association’s “Guidelines for Handling Molten Aluminium” is considered to be the industry’s best practices. It can be obtained here.

The Aluminium Times had an article last year about safety pit coatings. It can be viewed below.

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