On November 22, 2006, an explosion turned the town of Danvers, MA upside down. The explosion started in a chemical manufacturing plant, destroying it. The subsequent fires had far-reaching effects; it destroyed twenty-four homes, six business, and dozens of boats at a nearby marina. At least ten residents were hospitalized as a direct result of the explosion, and over 300 residents in the nearby neighborhood were evacuated. The cause? The plant was not storing flammable liquid in compliance with regulatory standards.
What are the hazards?
The two main hazards associate with flammable and combustible liquids are fires and explosions. This was disastrously illustrated in the explosion and fires in the Danvers, MA incident.
Other hazards include spills, ingestion, and absorption of these liquids. All these hazards can range in severity from minor to deadly.
Be a Better Supervisor
As a supervisor you can expect the management of your organization to:
- Provide proper storage for flammable liquids.
- Ensure proper training is provided to employees who work with flammable liquids.
- Ensure containers are properly labeled.
When it comes to your responsibilities as a supervisor, you may be asked to provide training in the use and storage of flammable liquids as well as:
- Monitor for proper use and storage.
- Inventory control by keeping only the minimum amount of these liquids required on hand.
- Ensure Safety Data Sheet (SDS) are current for all flammable liquids.
Careful monitoring of what processes use flammable and combustible liquids and frequent audits of the chemical inventory can help control the amounts of liquids on hand.
If you are missing updated Safety Data Sheets from manufacturer’s or supplier’s either go onto their website and download a copy or request a copy from them.
To monitor the storage, you need to be familiar with the different categories and classes of flammable and combustible liquids and their flashpoints because this is how they are classified. The maximum storage requirements are based on these classes and categories. This can get a bit tricky because of the different jurisdictional, state, and local regulations and fire and building codes.
You want to find out the maximum allowable amounts of flammable liquids you can store both in containers that are inside flammable liquids storage cabinets, in safety cans outside of the cabinets, and total quantities overall – both inside and outside of storage cabinets, in storage areas or fire compartments, and in tanks.
Once you have this information, conduct an audit of your flammable and combustible liquids to determine what classes and categories you have, based on their flashpoints, and compare what you have, to what you’re allowed to have.
And here’s something to keep it interesting. The terms “flammable liquids” and “combustible liquids” are still used in both the United States and Canada but under the Globally Harmonized Standard, GHS, the term “combustible liquids” is no longer used, and those liquids now all fall under flammable liquids.
Under GHS – all liquids with a flash point of not more than 199.4°F (93°C) are categorized as flammable liquids and flammable liquids are further subdivided into categories:
- Category 1 liquids have flash points below 73.4°F (23°C) and boiling points at or below 95°F (35°C).
- Category 2 liquids have flashpoints below 73.4°F (23°C) and boiling points above 95°F (35°C).
- Category 3 liquids have flashpoints at or above 73.4°F (23°C) and at or below 140°F (60°C).
- When Category 3 liquids with flash points at or above 100°F (37.8°C) are heated for use to within 30°F (16.7°C) of their flash point, they must be handled in accordance with the requirements for a Category 3 liquid with a flashpoint below 100°F (37.8°C).
- Category 4 liquids have flash points above 140°F (60°C) and at or below 199.4°F (93°C).
- When Category 4 flammable liquids are heated for use to within 30°F (16.7°C) of their flash points, they must be handled in accordance with the requirements for a Category 3 liquid with a flashpoint at or above 100°F (37.8°C).
In addition, the new rules specify that when a liquid with a flash point greater than 199.4°F (93°C) is heated for use to within 30°F (16.7°C) of its flash point, it must be handled in accordance with the requirements for a Category 4 flammable liquid.
- A flammable liquid was defined as “Any liquid having a flash point below 100°F (37.8°C)”.
- A combustible liquid was defined as “Any liquid with a flashpoint at or above 100°F (37.8°C), but below 200°F (93.3°C)”.
Flammable and combustible liquids were further subdivided into classes:
- All flammable liquids were Class I liquids.
- Class IA liquids had flash points below 73°F (22.8°C) and boiling points below 100°F (37.8°C).
- Class IB liquids had flash points below 73°F (22.8°C) and boiling points above 100°F (37.8°C).
- Class IC liquids had flash points at or above 73°F (22.8°C) and below 100°F (37.8°C)
- Combustible liquids were Class II or III liquids.
- Class II liquids had flash points at or above 100°F (37.8°C) and below 140°F (60°C).
- Class IIIA liquids had flash points at or above 140°F (60°C) and below 200°F (93.3°C)
- Class IIIB liquids had flash points at or above 200°F (93.3°C). When these chemicals were heated within 30°F (16.7°C) of their flash points, they were treated as Class IIA liquids.
It is possible you will have to reference both sets of criteria to make classification and storage decisions.
You can use this in conjunction with our Flammable and Combustible Workplan.