Are All D001 Wastes Flammable Hazardous Materials?

Posted on 2/25/2020 by Flip De Rea

Flip is an instructfor for Lion's Multimodal Hazmat Shipper Certification Workshops. Join LIon in Houston, Los Angeles, Denver, Las Vegas, Kansas City, Chicago, and St. Louis for reliable, up to date 49 CFR, IATA DGR, and IMDG Code training in Spring 2020. Save your seat today.

Ignitable and flammable are words that sound interchangeable; and may used as synonyms in casual conversation. But if you manage hazardous waste or ship hazardous materials, you know that ignitable and flammable each have distinct regulatory definitions, and both terms should raise a red flag for you.

Wastes identified by the Environmental Protection agency (EPA) as Ignitable hazardous wastes are assigned a D001 waste code and must be managed as hazardous waste on site, according to your RCRA generator status. Materials identified by the Department of Transportation (DOT) as Flammable require specific preparation and handling when moved from location to location.

Often, Ignitable wastes are flammable materials. Sometimes, though, they're not..

The Resource Conservation and Recovery Act (RCRA) identifies four ways that a waste might be assigned the Characteristic of Ignitability. Each different way will match up with at least one DOT regulated hazard class, but not necessarily the same DOT hazard class each time. Let’s look at the possibilities.

Ignitable Liquids 

The first RCRA description of an Ignitable waste is a liquid with a “flash point less than 60 °C (140 °F)”. If you’ve assigned a D001 waste code to your waste for that reason, then, when it comes to transport, your waste will meet the definition of DOT hazard class 3, Flammable Liquids; a liquid having a flash point of not more than 60 °C (140 °F).

Ignitable Non-liquids 

RCRA also describes Ignitable wastes as wastes that are “not a liquid” and are “capable of causing fire through friction, absorption of moisture or spontaneous chemical changes and, when ignited, burns so vigorously and persistently that it creates a hazard”.

If you’ve assigned a D001 waste code to your waste for one of those reasons, then, when it comes to transport, your waste will likely meet one of the definitions of DOT hazard class 4.

Hazard Class 4 is split into three divisions.

Division 4.1 refers to “flammable solids”. (capable of causing fire through friction)

Division 4.2 is for “spontaneously combustible materials”. (capable of causing fire through spontaneous chemical changes) 

Division 4.3 is for materials that are “dangerous when wet”. (capable of causing fire through absorption of moisture)

Further analysis would be required to establish your non-liquid waste's exact characteristics to properly classify it for transportation under 49 CFR hazmat regulations.

Ignitable Compressed Gases 

RCRA also describes Ignitable wastes as wastes that are “an ignitable compressed gas”. If you’ve assigned a D001 waste code to your waste for that reason, then, when it comes to transport, your waste will likely meet the definition of DOT division 2.1, Flammable Gas. In this case the EPA and the DOT have similar, but distinct, definitions of “compressed gas” and some legwork would be required.

Ignitable Oxidizers 

RCRA also describes Ignitable wastes as wastes that are “an oxidizer”. If you’ve assigned a D001 waste code to your waste for that reason, then, when it comes to transport, your waste will likely meet the definition of DOT division 5.1, oxidizers. Here again, US EPA and US DOT maintain different (but similar) definitions of “oxidizer” and some ground-truthing would be required.

While the words ignitable and flammable largely mean the same thing, understanding the subtle differences and proper uses of these two terms is critical to avoid noncompliance with RCRA and 49 CFR hazmat regulations.  

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Tags: Classifying hazmat, hazardous materials regulations, hazardous waste management, hazmat shipping, RCRA

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