What You Need to Know About Hazardous Locations as a Homeowner

Hazardous locations or areas, also known as HazLoc, are important to be aware of. The term itself is a bit broad and ambiguous and you might automatically assume this refers to places such as factories and chemical plants, but private homes alike could be considered hazardous locations. In this article, we will run through all things concerning hazardous locations in your house.

The goal of this concept is to understand which areas of your house can be dangerous and what you can do to mitigate hazards when working in your home. This way your future DIY project will be as safety-conscious as possible. 

What is a Hazardous Area?

While this is a term commonly used in industry, it can also apply to various parts of your home.

Broadly speaking, a hazardous location is a place where there is some sort of risk to your health and safety. This can be in the form of a fire hazard, explosion hazard, shocking hazard, or where there are toxic substances. Identifying these hazardous areas is required by industry regulation and is crucial to workplace safety.

Knowing what kind of hazards you might face allows you to prepare accordingly, not only in terms of what precautions you will take but also in what equipment you will need to use. In the United States, hazardous areas and substances are classified by the Occupational Safety and Health Administration, or OSHA for short.   

Types of Hazardous Areas in the Home

Propane tanks must be handled with care so that they do not pose any explosion risk.

Officially, there are three classes of hazardous locations defined by OSHA. This is outlined in the National Electric Code, or NEC, a document that defines hazardous locations as areas “where fire or explosion hazards may exist due to flammable gasses or vapors, flammable liquids, combustible dust, or ignitable fibers or flyings”.

The NEC Hazardous locations list is mainly geared towards how these hazards relate to the use of electrical equipment as, of course, anything that generates a spark is also liable to potentially cause fires or explosions. 

Anywhere Fuel is Stored 

Per area hazard classification, which broadly describes all Class I hazardous locations, it is a place where there are flammable gasses or vapors in the air. This includes natural gas vapors as well as gasoline vapors. So, a typical class I division I hazardous location would be somewhere like a petroleum refinery. When such substances are found in the air there is a latent risk of a fire or explosion which can be ignited by an electrical source.

To reduce explosion hazards, do not use anything other than a purpose-made jerrycan for storing gasoline.

As such, any enclosed space such as a garage or shed where you have propane tanks or fuel jerrycans requires additional precautions. Avoid doing any kind of work using equipment that can cause sparks or other ignition sources. It is also advisable to keep any place where vapors are present well-ventilated as this will further reduce the risk of explosions. Good ventilation will also reduce the incidence of other dangers, such as black mold, particularly in a moist humid climate.   

Areas With High Levels of Particulate Matter

Workspaces with a high level of combustible dust are referred to as Class II division I hazardous locations. This hazardous location classification means that the area is filled with finely pulverized materials suspended in the atmosphere and can cause a powerful explosion if there is an ignition source.

Wearing a HEPA mask is highly advisable if you plan to work in an environment with a lot of particulate matter, such as sawdust.

This means that facilities such as plastic factories, magnesium plants, four mills, and grain elevators all are class II hazardous locations. Of course, there really aren’t these kinds of areas in the home; the average residence is not going to be full of explosive powders. However, if you do a lot of DIY work and construction around your house, this can include those areas; usually garages or sheds. Nonetheless, a class II division hazardous location requires special care to reduce the risk of explosions including good electrical insulation and effective ventilation. 

Flammable Areas (Insulation, Other Flammable Parts of Home)

Any place with lots of easily ignitable fibers or flyings is categorized as a class III area. So, basically anywhere with a lot of cotton fibers, flax fibers, wood pulp, or other flyings are class III hazardous location. A lumber mill or a cotton gin are both classic examples of this kind of hazardous location.

In your home, a class III area can be any place where there is a lot of sawdust or fibers from flammable insulation. In these kinds of hazardous locations, anything from a spark to hot metal can cause a conflagration. Because of this, it is crucial to take fire mitigation measures so that fires do not start easily and spread slowly.  

Hazards and How to Avoid Them

Many devices such as car starter motors produce sparks which can pose a hazard in class I hazardous locations.

Regardless of what kind of NEC hazardous location you find you are working in, you will find some common ignition risks that need to be protected against. Since our central goal is to reduce the likelihood of fires or explosions, it is a good idea to know what can cause them. This way we can be as well-prepared as possible and ensure electrical hazardous location safety. 

High Temperatures

Some types of equipment that you might use on a job site produce a lot of heat and this can be a significant risk in a hazardous location. In particular, lamps and lighting fixtures can get quite hot, especially if they use incandescent bulbs. Without proper measures these lights can get so hot they ignite certain materials. To reduce the danger of this happening, only use certified equipment such as inspection lamps, as these are designed so that they will not cause explosions.

Likewise, power tools of various sorts can also get quite hot and any metal parts can get hot enough to cause hazardous materials to catch fire or explode. As such, it is critical to practice common sense safety measures by refraining from using tools that cause a lot of heat and/or friction. For instance, a power drill and a circular saw are both power tools you don’t want to use in hazardous spaces as they produce enough heat to set flammable materials alight.  

Arcing and Sparking

Arcs and sparks are other risks that you’ll have to be mindful of. In a non-hazardous space, plenty of devices produce sparks as part of normal operation. Your lightswitches can produce sparks, some power tools produce sparks, and automotive starter motors also produce sparks.

Outside of an electrical hazardous location, you don’t have to worry about this, but this is a central concern within a hazardous area. Any equipment that produces sparks can ignite a fire or detonate an explosion, and as such, should be kept well away from any hazardous locations in your house. So, for example, a fuel storage area is not the place for electrical sparks due to the heightened risk of ignition.

Equipment with frayed cables can cause electric arcing and therefore pose a major fire hazard.

Alas, most parts of a home are going to have electrical wiring running through them, and so another aspect of workspace safety is preventing electrical arcing in a hazardous location. Arcing is when an electrical current unintentionally ‘jumps’ from one conductor to another, producing significant heat and posing an obvious ignition risk. The best way to make your electrical hazardous location safe is to get an electrician involved. A licensed pro is going to be far more knowledgeable in this realm and will be able to safely modify your electrical system to reduce the risk of arcing. They will also have the proper protective gear and equipment to be able to reduce risk and handle a dangerous situation, should an accident occur.

Your Equipment

One potential risk in hazardous locations that is often overlooked is your own equipment. Even if you avoid dangerous equipment and use only tools that are allowed by OSHA in various hazardous locations, your equipment can still be a hazard if it is poorly maintained. Equipment that is not taken care of has a higher chance of malfunctioning.

An inspection lamp, for example, could short-circuit and then become an ignition source. Power Tools with frayed or exposed cables can pose a similar risk of ignition or even electrocution. HEPA masks - widely used in a lot of hazardous locations - can become dangerous if their filters are not regularly swapped out.  

Dangerous Substances

Asbestos crystals pose a major threat to respiratory health and must be removed from a home by mitigation specialists.

Beyond the general, there are also a few key dangerous substances to watch out for when you are working in any hazardous space. These materials are especially prevalent in older homes which may have been built before certain materials were identified as dangerous and thereby banned in building codes. 

Asbestos 

Asbestos is well-known in the world of the industry for its amazing fire resistance and durability. Unfortunately, it is also a major carcinogen that tends to flake as it decays. Breathing these flakes in can lacerate your lungs and cause major health problems later in life. If you believe that your home contains asbestos - usually found in roofing and insulation - it is imperative to contact a mitigation specialist right away.  

Heavy Metals

Materials such as lead are known as heavy metals because of their high density. Lead is by far the most popular heavy metal found in homes, although cadmium is also common. These metals can be found in paint, insulation, and even in plumbing. Lead that has been disturbed either by renovations or decay poses a major health risk and can even cause brain damage if ingested. As with asbestos, the main way of fighting against lead is by scheduling a home inspection with a mitigation specialist.

Lead was often mixed into paint and this can pose a major health risk as the paint flakes from age.

Fiberglass Insulation

Fiberglass was once quite popular as a durable form of affordable insulation, but mounting evidence shows that it has a tendency to flake with time. These flakes then enter the air and, if breathed in, get trapped in the lungs, causing lacerations and long-term health problems. If you have to work with fiberglass, ensure you wear a mask and that any exposed skin is covered so that the fibers have no chance of touching you. 

Rodent Droppings 

More than just a moldy smell in the basement, rat droppings are a major vector for various diseases that can be transmitted to humans and pets. As such, it is recommended you wear a HEPA mask and cover yourself up when working in a hazardous environment of this nature. Rodent droppings and fiberglass insulation alike are most commonly found in places such as the attic - so keep this in mind especially when you’re wanting to revamp the attic into a movie room or fun clubhouse for your kids.

By being mindful of these classifications and taking precautions you will keep your workspace and your house safe and away from the risk of harm. At the end of the day, just a few small common sense measures can vastly decrease the chance of something going wrong. Nobody wants their renovation to end in injury, so let’s all work to be smart and safe - and most importantly, informed about the hazardous locations that can be found in our very homes.