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Permit Space Triggers – Other Recognized Serious Safety or Health Hazards

November 7, 2023 by Curtis Chambers Leave a Comment

Other Serious Safety Health Hazards OSHA Confined Spaces

Blog Post #16 – In this post to The Confined Space Training Blog, we examine the fourth and final criteria listed in OSHA’s definition of a permit-required confined space. And that is, any confined space that contains any other recognized serious safety or health hazard.

OSHA Definition of Other Recognized Serious Safety or Health Hazards

In the OSHA confined space standards for general industry or construction, there is no specific definition for the phrase “other recognized serious safety or health hazard.” However, in the preamble to the Confined Spaces in Construction standard, OSHA explains they are taking about “hazards that could impair the ability of an entrant to exit the space without aid.” They continue on in that preamble to state that “The key determination is the likelihood that death or serious harm will occur IF an accident or exposure occurs.”

Examples of Other Recognized Serious Safety or Health Hazards

Based on the above-mentioned statement made by OSHA in the preamble, one example of a serious safety hazard present in confined spaces at many general industry and construction worksites is mechanical hazards such as unguarded fan blades. The same can be said about agitators and mixing blades present inside of a confined space such as a mixer or agitator. Other similar hazards include moving gears, belts and pulleys, or chains and sprockets. Also covered would be equipment that could move and crush a person, such as an elevator car. And, exposed live electrical equipment and uninsulated conductors inside of a confined space could also present a serious safety hazard to entrants. 

A confined space with a high internal temperature, such as a furnace, oven, or boiler, could represent a serious safety hazard to an employee working inside. So would a confined space containing a steam line or related equipment that could burn or scald an employee who is working on it. And any confined space containing water or some other liquid deep enough for an employee to potentially drown is also a serious safety hazard.

Hazardous equipment used in many work activities conducted inside confined spaces must also be considered for the potential to serious harm a confined space entrant. For example, high-pressure abrasive blasting equipment (e.g.: sand blasting), large abrasive-wheel grinders, and saws with large blades could all cause an entrant to suffer deep cuts or lacerations accompanied by heavy bleeding.

Another example of a potentially serious safety hazard inside a confined space is the presence of highly caustic or corrosive materials that could cause injury to an entrant. Biological or radiation hazards present in high levels inside a confined space could also be dangerous in some situations. Even a reasonable potential for venomous snakes and other dangerous animals or insects must be considered in some work environments, as they could represent a serious safety hazard to an entrant.

There is one more potential safety hazard that OSHA discusses at length in the preamble to the OSHA construction standard for confined space entry, and which could also be applicable in some general industry spaces. That is a low-hanging object, such as a beam or piece of angle iron, that a worker could strike their head on and becoming disoriented, or even being rendered unconscious.

So, when you are evaluating confined spaces for “other recognized serious safety or health hazards,” remember that OSHA explains in the preamble to the standard that their concern here is “any hazards that could impair the ability of an entrant to exit the space without aid.”

Additional Examples of Recognized Serious Safety or Health Hazards in Confined Spaces?

There is no doubt many other examples of recognized serious safety or health hazards that could reasonably be expected to be present inside of confined spaces. So, please provide other examples of “other recognized serious safety or health hazards” with a reasonable potential to be present in confined spaces in the comments section below. You can also ask questions there as well.

Then, be sure to come back later and read our next blog post about steps to be taken when you identify permit-required confined spaces in the workplace; this includes steps that need to be taken even if you or your employees do not enter into permit-required confined spaces.

Last but not least, I encourage you to take a moment and spread the word about our confined space training blog by sharing a link to this post with others in your network, so they too can benefit from this information. Thanks – Curtis

Filed Under: Permit Required Confined Spaces Tagged With: 1910.146, 1926 subpart AA, OSHA permit required confined space entry standard, other recognized, safety hazard, serious

Definition of a Hazardous Atmosphere – Toxic Substance Exceeding the OSHA PEL

June 2, 2023 by Curtis Chambers Leave a Comment

OSHA Hazardous Atmosphere Toxic PEL

Blog Post #12 – In this post to The Confined Space Training Blog, we will examine the fourth category listed in the Federal OSHA definition for a hazardous atmosphere, which is an atmosphere that contains any toxic substance present in quantity greater than its permissible exposure limit, or PEL.

Before moving on, make certain to pay close attention to an important footnote to this definition in the OSHA definition section for this standard. OSHA states that this category of hazardous atmosphere only applies “if the topic substance can cause death, incapacitation, impairment in ability to self-rescue, injury, or acute illness due to its health effects.”

For example, exposure to ammonia in the atmosphere at levels above its PEL for an extended period of time would cause the entrant to experience burning eyes and throat, difficulty breathing, and make it extremely difficult to function normally; exposure to extremely high levels could even lead to death. This condition would meet the definition of a hazardous toxic atmosphere in the confined space standards. However, exposure to silica or asbestos at levels over their respective PELs, although harmful in the long term, would typically not cause any immediate reaction. So, overexposure to those particular substances would not meet the definition of a hazardous atmosphere as defined in the OSHA confined space standard (although normal protective measures required by other OSHA standards would still be applicable).

What are OSHA PELs?

The term PEL represents the maximum exposure level for a particular contaminant that an employee may be exposed to at work, averaged over a specified period of time, without suffering negative health effects or needing to take protective measures such as use of a respirator. PELs for various contaminants are established by Federal OSHA and are listed in different parts of the OSHA code of federal regulations.

Part 1910 lists the PELs that apply to general industry worksites. Part 1926 for construction and Part 1915 for shipyards also have PELs, and some of those may differ from those listed in Part 1910. In addition, many states operate their own OSHA approved state program. Some have adopted the federal OSHA PELs, but a few states have established their own PELs, some which are lower than federal OSHA’s.

In addition to the mandatory OSHA PELs, there are some other voluntary limits that you may hear mentioned. For example, The American Conference of Governmental Industrial Hygienists, or ACGIH, has developed threshold limit values, or TLVs, for many substances. And The National Institutes of Occupational Safety and Health, or NIOSH, developed recommended exposure limits, or RELs, for many substances. These are based on more recent research than the OSHA PELs in many cases, and may be set lower (or higher) than the OSHA PEL for some substances.  Employers MAY voluntarily choose to utilize these lower limits instead. Also, these voluntary limits are often utilized when OSHA has not established a mandatory PEL for a specific substance.

The permissible exposure limits for most individual substances in gas and vapor form are presented as parts per million, or PPM, which is a way to measure very small quantities of toxic air contaminants at a molecular level. The more toxic the substance, the lower the PEL. For example, the 1910 General Industry permissible exposure limit for ammonia is 50 ppm.

To help visualize the concept of substances being measured in parts per million, or ppm, consider this; if a contaminant evenly dispersed in a space makes up one half of the total atmosphere in that space, it would be measured at 500,000 ppm. If the substance made up 5% of the total atmosphere, it would be measured at 50,000 ppm, and if a substance made up 1% of the total atmosphere, it would measure at 10,000 ppm. A substance making up one tenth of 1% of the total atmosphere would measure at 1,000 ppm, and a substance making up one one-hundred-thousandth of a percent would be measured at 10 ppm. And a few substances are so toxic, their permissible exposure limits are actually measured in parts per billion, or PPB.      

The table below shows the federal OSHA PELs for a few common toxic substances found in some confined spaces.

OSHA Permissible Exposure Limits Confined Spaces

Different Types of OSHA PELs

Unless noted otherwise, OSHA permissible exposure limits are based on an “eight-hour time-weighted average,” also known as TWA.  8-hour TWA means that the employee exposure to the substance is averaged over an eight-hour work shift. For example, the OSHA PEL for acetone is listed as 1,000 ppm, which is averaged over 8 hours.

Some permissible exposure limits are appended with a designation of ST or STEL, which stands for “short term exposure limit.” This is an exposure limit that is averaged over a shorter, 15-minute time period, as opposed to the 8-hour period. For example, the PELs for benzene are listed as 1 ppm based on an 8-hour TWA, but a STEL of only 5 ppm.

A few other substances are marked with the letter C, which stands for ceiling limit. For example, the PEL for chlorine is a ceiling limit of only 1 ppm. This limit is instantly reached any time the employee is exposed to the substance at the level specified.

It is important for employers to identify the toxic substances that employees may be exposed to when entering confined spaces. It is also important for entrants and attendants to know about the modes of exposure, as well as the signs and symptoms of overexposure, to toxic substances. This information can usually be obtained from each substance’s safety data sheet, or SDS.

Toxic Atmospheres in Confined Spaces

So, in review, a hazardous atmosphere exists where a toxic substance is present in a quantity greater than its permissible exposure limit (PEL). This can occur in confined spaces such as, but not limited to, tanks and vessels where a toxic product has been stored or is being utilized, and in underground spaces, such as crawl spaces, utility vaults and sewers, where a hazardous substance such as hydrogen sulfide (H2S) can migrate into the space.

Also, toxic gases such as CO can be created by equipment such as generators, chop saws, and compactors that are powered by internal combustion engines. As a reminder, if there is a hazardous substance for which OSHA has not established a PEL, refer to that substance’s safety data sheet, or SDS, for exposure recommendations and guidelines.

In our next blog post (#13), we will examine the fifth and final criteria of a hazardous atmosphere that could be present inside of a confined space (any other IDLH atmosphere). In the meantime, please provide your feedback to this blog post about toxic atmospheres in the comments section below.

And as always, I hope you will take a moment to spread the word about our confined space training blog by sharing a link to this post with others in your network so they can benefit from this information. Thanks – Curtis

Filed Under: Permit Required Confined Spaces Tagged With: 1910.146, 1926 subpart AA, ceiling limit, hazardous atmosphere, OSHA permit required confined space entry standard, PEL, STEL, toxic, toxicity

Definition of a Hazardous Atmosphere – Flammable Gas, Vapor or Mist >10% LFL

February 24, 2023 by Curtis Chambers 6 Comments

Hazardous atmosphere flammable gas vapor or mist greater than 10% LFL or LEL

 Blog Post #9 – In previous blog posts, we discussed how to identify confined spaces, and provided several examples of such spaces. Next we will examine the factors that determine whether or not each confined space identified at your workplace must be classified as a permit-required confined space, starting with a hazardous atmosphere that contains a flammable gas, vapor, or mist in excess of 10% of its lower flammable limit, or LFL.

 OSHA Definition of a Permit-required Confined Space

The Federal OSHA definition of a permit-required confined space for general industry can be found in 1910.146, paragraph B, titled definitions, and in 1926.1202, also titled definitions, for the construction industry. That is where OSHA lists the four types of hazards that require a confined space be classified as a permit required confined space. Those four types of hazards are:

  • The space contains an actual or potential hazardous atmosphere;
  • The space contains a material with the potential to engulf the entrant;
  • The space is configured to trap or asphyxiate the entrant; or;
  • The space contains some other recognized serious safety or health hazard.

 What is a Hazardous Atmosphere?

 The Federal OSHA definition for “hazardous atmosphere”, the first classification listed above, is also found in 1910.146, paragraph B, definitions, for general industry, and in 1926.1202, definitions, for the construction industry.

There are five different types, or classifications, of hazardous atmospheres, listed in these two OSHA definitions. Those classifications, which are nearly identical in the two standards, are:

 (1) – Flammable gas, vapor, or mist in excess of 10 percent of its lower flammable limit (LFL);

 (2) – Airborne combustible dust at a concentration that meets or exceeds its LFL;

 (3) – Atmospheric oxygen concentration below 19.5 percent or above 23.5 percent;

 (4) – Atmospheric concentration of any substance for which a dose or a permissible exposure limit is published in subpart G, Occupational Health and Environmental Control, or in subpart Z, Toxic and Hazardous Substances, of this part and which could result in employee exposure in excess of its dose or permissible exposure limit;

 (5) – Any other atmospheric condition that is immediately dangerous to life or health.

 The balance of this particular blog post focuses on the first category of a hazardous atmosphere listed above, which is a flammable gas, vapor, or mist greater than 10% of its lower flammable

Greater Than 10 Percent Lower Flammable Limit (LFL)

 OSHA includes this type hazard because they do not want employers to wait until conditions are ripe for a flash fire or explosion to occur inside of a confined space before taking precautionary measures. Atmospheric conditions inside a confined space that contain a low level of flammable gas, vapor, or mist could quickly change for the worse. Therefore, OSHA regulations classify a flammable gas, mist, or vapor present inside a confined space at levels over 10% of its LFL as a hazardous atmosphere. Once that level is reached inside a confined space, or if there is a reasonable probability that it will develop within the space during entry operations, that space must be classified as a permit-required confined space.

 Lower Flammable Limit (LFL) Explained

 So, what is LFL? It stands for Lower Flammable Limit. The LFL is the minimum amount of a particular flammable gas, vapor, or mist that must be present in the atmosphere to ignite and burn. If you introduce an extremely small amount of a flammable gas, vapor, or mist into the atmosphere of a confined space, it might not ignite when exposed to an ignition source (such as a spark or flame) because there is not enough of the material present to form a flammable mixture in the air. How much flammable gas, vapor, or mist is needed in the atmosphere for a fire or explosion to occur? That depends on the gas, vapor, or mist present inside either space, as they all have a different LFL.

 What is LEL?

Be aware the term “LFL” is also referred to as “LEL”, or Lower Explosive Limit. The terms LFL and LEL are basically interchangeable. While OSHA uses LFL in their confined space standards, LEL is commonly used by many gas detection equipment manufacturers, as well as in many written confined space entry programs. Also, I may on occasion use the term LEL throughout future blog posts.

 LFLs of Common Flammable Gasses

The LELs of a few common combustible materials are listed in the chart below. An LEL is expressed as a percentage of the atmosphere within the confined space that is comprised of a particular combustible gas, vapor, or mist. For example, the LEL of Methane gas, with the chemical identifier of CH4, is 5% of the atmosphere at any given point. As you can see, the LELs of various gases differ quite a bit. 

Upper and lower flammable limits of common gasses

What does UFL mean?

Note that each of the combustible materials listed in the chart also have their own UFL, or Upper Flammable Limit (expressed in the chart as an UEL). If a flammable gas, vapor, or mist is present in the atmosphere in quantities greater than its UFL, it will not ignite and burn. I bring up this term because while OSHA does not regulate UFLs, they do come into play when we discuss gas detection equipment in later blog posts.

Flammability Characteristics of Methane Gas

As mentioned earlier, the LFL of Methane gas is 5%. So, if Methane gas is present in a confined space, but it does not make up at least 5% of the atmosphere at any point within the space, there will be no flash fire or explosion if there is a spark or other source of ignition. And the upper flammable limit, or UFL, of Methane gas is 15%; So, a confined space containing higher levels of Methane would not burn or explode either. However, if the amount of Methane gas increases or decreases to fall somewhere between its LFL and UFL at any point inside a confined space and there is any source of ignition in that same area, a fire or explosion will occur.

Since Methane gas has an LFL of 5% of the atmosphere, a hazardous atmosphere as defined by OSHA would be present inside a confined space if the amount of Methane gas in the atmosphere exceeds 10% of that level. The presence of that level of Methane gas, which equates to just 0.5% of the total atmosphere, means the space would have to be classified as a permit-required confined space.

Other Hazards Associated with Methane Gas

Before moving on, let’s take a moment to discuss Methane gas, or CH4, a little more, as this is a hazardous gas commonly found in a variety of confined spaces. Methane is a colorless, tasteless gas that has no odor, so its presence cannot be detected by your senses alone. But too much Methane gas inside of a confined space creates not only a potentially flammable atmosphere, as previously discussed, it can also displace oxygen in the space, creating a deficiency of oxygen for an entrant to breathe. Fortunately, while Methane is a highly flammable gas that can also displace oxygen, it is one of the few flammable gases that is not toxic.

Where is Methane Gas Commonly Found?

Methane is created when organic matter decomposes. Therefore, it is commonly found in potentially harmful quantities within confined spaces such as sewers and related facilities, manure pits, and in silos that have held grain or similar materials that has rotted. Methane is also commonly found in confined spaces such as underground utility vaults, especially those located near landfills (the rotting trash creates Methane). Therefore, these spaces are typically classified as permit-required confined spaces.

More Examples of Confined Spaces With Potentially Flammable Atmospheres

Other examples of confined spaces with a reasonable potential to contain an atmosphere containing a flammable gas, vapor, or mist above 10% of its LFL include pipelines, tanks and other vessels that have contained fuels or other flammable or combustible materials, even when they have been emptied of their contents. Also, confined spaces where work processes such as cutting with an oxy-acetylene torch or painting with flammable paints and solvents is taking place inside could potentially contain a hazardous atmosphere. And confined spaces such as vaults or tunnels in which there are leaking valves or piping used to transport flammable gas could also contain a hazardous atmosphere. As such, each of these spaces would also likely be classified as a permit-required confined space.

So, in review, any confined space with an actual flammable gas, vapor, or mist present at levels greater than 10 percent of its lower flammable limit, or LFL, is considered to have a hazardous atmosphere. And that means the space must be classified as a permit-required confined space. The same is true for any confined space in which that level of a flammable atmosphere could reasonably be expected to develop during entry operations. You may also hear the term LEL, which stands for lower explosive level, being used to describe a hazardous flammable atmosphere inside a confined space, as that term is synonymous with LFL.

In our next blog post (#10), we will examine the second criteria of a hazardous atmosphere that could be present inside of a confined space (combustible dust). In the meantime, please provide your feedback and questions to this blog post in the comments section below. And as always, I urge you to share a link to this confined space training blog post with anyone in your network who could benefit from this information. Thanks – Curtis

Filed Under: Permit Required Confined Spaces Tagged With: 1910.146, 1926 subpart AA, flammable atmosphere, hazardous atmosphere, LEL, LFL, lower explosive limit, lower flammable limit, methane gas, OSHA permit required confined space entry standard

OSHA Requirement for a Competent Person to Identify Permit Required Confined Spaces

October 21, 2022 by Curtis Chambers Leave a Comment

Confined Space Competent Person

Post #5 – The success of an organization’s confined space entry program is ultimately predicated on having a competent person with the ability to identify and evaluate the confined spaces at their work sites to determine whether or not they meet the OSHA definition of a permit-required confined space. And that takes a person with sufficient training and experience to do the job right. But exactly whose job is it to identify and evaluate confined spaces?

Here’s what the OSHA confined space regulations say about that.

OSHA Requirements to Evaluate Confined Spaces

The first paragraphs from the general requirements sections of the OSHA confined space entry standards for general industry and construction, respectively, are listed below:

GENERAL INDUSTRY

1910.146(c)(1) – The employer shall evaluate the workplace to determine if any spaces are permit-required confined spaces.

CONSTRUCTION

1926.1203(a) – Before it begins work at a worksite, each employer must ensure that a competent person identifies all confined spaces in which one or more of the employees it directs may work, and identifies each space that is a permit space, through consideration and evaluation of the elements of that space, including testing as necessary.

As you see, both of these performance-based confined space standards place the onus on employers, either individually or through a designated Competent Person, to evaluate their workplaces to determine if any confined spaces are present. Then, they must determine if any of those confined spaces are to be categorized as a permit required confined space, or alternatively, as a non-permit-required confined space.

Special Qualifications or Certifications Needed to  Evaluate Confined Spaces?

While OSHA requires employers to ensure the confined spaces at their worksites are identified and evaluated, their standards do NOT require the completion of any specific training class or “competent person certification” for confined spaces for the person conducting the evaluations. Instead, an OSHA compliance officer would simply speak with whomever the employer has appointed as their competent person to perform the confined space evaluations, and determine if they seem to have adequate experience, training certification, and knowledge needed to do the job competently.

Duties of the Competent Person Evaluating Confined Spaces

The competent person who is designated to evaluate the confined spaces at a worksite to determine whether or not they are permit spaces must be capable of effectively performing the following three tasks for the worksite in question:

  • Identify all confined spaces at the worksite after consideration of all facets of the OSHA definition of a confined space;
  • Determine if each confined space identified at the site will be categorized as a permit-required confined space, or as a non-permit confined space;
  • When conditions demand, re-evaluate (and possible reclassify) a non-permit confined space, should the configuration of that space change in a manner that could cause it to become a permit-required confined space (especially true during progression of the construction process when building a confined space such as a tank). Re-evaluation of a non-permit required confined space must also be performed every time there is a work process or activity taking place inside of, or near, any non-permit confined space which could potentially introduce new hazards that require the non-permit space be reclassified as a permit-required confined space.

In many cases, an employer also will have the person designated as their competent person for confined space identification to serve as the entry supervisor for their confined space entry crew. However, doing so is not a strict requirement of the confined space standards, as those two roles could be filled by different personnel.

OSHA Documentation Requirements for Confined Space Evaluations

In case you were wondering, there is no requirement in the federal OSHA confined space entry standards requiring the employer to document their confined space evaluations; however, some employers may choose to do so anyway.

Identifying Permit-Required Confined Spaces at Multi-employer Worksites

OSHA gives employers working at a multi-employer job-site such as but not limited to construction sites the option to collaborate on identifying permit spaces at a worksite, by agreeing to use one designated competent person to perform the initial surveys. Or they can choose to use their own designated competent person to perform the surveys. But either way, each employer who has an employee who will enter into a confined space is ultimately responsible for compliance with the requirements of the OSHA confined space entry standards, and must therefore utilize due diligent before deciding to count on another employer’s competent person to perform the evaluations.

Designation of a Person Competent to Identify Permit-required Confined Spaces

Obviously, the wide variety in types of confined spaces and the assortment of potential hazards inside of those spaces will vary greatly from site to site. So, a competent person with training and experience in dealing with only one specific type of confined space may be capable of evaluating the spaces in a worksite if it only contains the same types of spaces with which they are already familiar. But that same person may or may not be suitable for evaluating the confined spaces of a type they have not experienced before. Only the employer can decide, based upon his or her knowledge of, and experience with permit required confined spaces, who is adequately prepared and able to be designated as being their competent person responsible for identifying permit-required confined spaces at the workplace.

Coming up in the next blog post (#6); we will start a deep dive into understanding the OSHA definition of a confined space.

Final Note: Thanks for reading the blog. Please help spread the word about our confined space entry training blog by sending a link to the blog to others in your network who could benefit from this information. Thanks – Curtis

Filed Under: Permit Required Confined Spaces Tagged With: 1910.146, 1926 subpart AA, competent person, evaluation, identify, non permit, OSHA permit required confined space entry standard, OSHA requirements

Understanding the Scope and Application of OSHA’s Various Permit Required Confined Space Entry Standards

October 11, 2022 by Curtis Chambers Leave a Comment

Which OSHA Confined Space Entry Standards Apply

Post #4 – As mentioned in an earlier blog post (#2), OSHA has three different sets of confined space entry standards; one applies to construction work, and another applies to general industry work. OSHA also have a standard that applies to confined space work conducted in the Maritime industry, but that standard will not be discussed in this blog post.

It is imperative that you understand which of the OSHA standards apply to your particular confined space entry operations, and conversely, which one does not, as the requirements of each standard differ. And the way to make sure you understand is to refer to the sections that list the scope and the application for each of the OSHA confined space entry permit requirements.

Scope of the OSHA Confined Space Entry Standards Applicable to General Industry

1910.146(a) lays out the scope of the OSHA permit-required confined space entry standards for general industry workplaces. It states:

“This section contains requirements for practices and procedures to protect employees in general industry from the hazards of entry into permit-required confined spaces. This section does not apply to agriculture, to construction, or to shipyard employment (parts 1928, 1926, and 1915 of this chapter, respectively).”

To reiterate information provided in post #2, general industry work typically consists of activities performed during the manufacturing of goods or products, including those at chemical plants and refining operations. General industry work also includes most general maintenance activities. Service industries such as telephone and cable companies, restaurants, coffee shops and bakeries are also covered by the OSHA 1910.146 general industry standards for confined space entry, as are warehousing and logistics operations and the healthcare industry. 1910.146 would even apply to work involving entry operations at establishments such as bowling allies and amusement parks.

Scope of the OSHA Confined Space Entry Standards Applicable to Construction

For the construction industry, 29 CFR 1926, paragraph 1201(a) explains the scope of the confined spaces in construction standards. This paragraph states the following:

“This standard sets forth requirements for practices and procedures to protect employees engaged in construction activities at a worksite with one or more confined spaces.”

According to 1910.12(b), work regulated under 1926 subpart AA construction standards applies only to confined space entry operations related to construction, alterations, and/or repairs, which include painting and decorating. This would include, but is certainly not limited to, confined space entry work involved in the construction of a brand-new structure, major renovation or repair of all or part of an existing structure, repainting portions or all of a structure, and demolition work. 

Which Confined Space Standard Takes Precedence?

Here is the tricky part; while the 1926 subpart AA confined spaces in construction standard does not apply to general industry work, that standard does apply to construction work conducted inside of a confined space that happens to be located at a general industry worksite.

Consider the following hypothetical of how entry into a tank, which as we will see in an upcoming blog post is usually considered a confined space, could feasibly be regulated by both the OSHA confined space entry standards for construction and also the confined space standards for general industry, switching back-and-forth over the course of time. Notice how the determination depends on the work activities that are taking place, and not the location.

  1. A large tank is fabricated in the shop at a manufacturing company, including having a protective lining sprayed onto the interior tank surfaces by a worker: this work is regulated under 146 General Industry requirements for confined space entry.
  2. The tank is erected at a chemical plant expansion project, where workers enter the tank to install fill lines and drain pipes: this work is regulated under 1926 Subpart AA Construction requirements for confined space entry.
  3. After the chemical plant is up and running in normal production, entry is made into the tank once a year to conduct an inspection of the protective lining on the interior surfaces of the tank to determine its general condition: this preventive maintenance work is regulated under 146 General Industry requirements for confined space entry.
  4. After an annual inspection discovers damage to the lining caused when the tank was previously struck by a forklift, a lining crew enters the tank to blast out the old lining and reapply a new tank lining: this repair work is regulated under 1926 Subpart AA Construction requirements for confined space entry.
  5. Subsequent annual entries are made to conduct inspections of the interior lining to determine its general condition: this preventive maintenance work is regulated under 146 General Industry requirements for confined space entry.
  6. After 30 years of use, the tank has been deemed obsolete, and is scheduled to be demolished. A crew enters the tank to cut loose interior braces and baffles as part of the tank demolition process; this demolition work is regulated under 1926 Subpart AA Construction requirements for confined space entry.

As the previous set of scenarios demonstrate, the over-riding factor to determine which set of OSHA confined space entry permit requirements apply to a given situation is usually the type of work (general industry or construction) being performed inside the confined space, as opposed to the location where the confined space work happens to be taking place.

Application – Workplaces Where OSHA Confined Space Standards Do Not Apply

I will wrap up this blog post by touching certain employers to whom the OSHA confined space entry permit requirements do not apply. The OSH Act of 1970, which establishes coverage of federal OSHA standards, was originally written to apply only to private sector employers in the U.S. and its territories. That means public employers like state and local government agencies (e.g.: municipalities and counties) are not regulated by the OSHA standards, including those for confined space entry operations, unless they happen to be located in one of the states or territories operating under a State Plan OSHA program, as explained in a blog post #2.

Also exempt from coverage by the OSH Act, and therefore exempt from the federal OSHA confined space entry standards, are workplaces for which other federal agencies have laws that regulate employee safety in certain operations. For example, entry into underground mines, which logically seem to be confined spaces, are actually covered by the Mine Safety and Health Administration (MSHA) regulations, and are therefore exempt from OSHA standards for confined space entry. And construction work conducted at worksites overseen by the U.S. Army Corp of Engineers must follow the EM-385-1-1 requirements for confined space entry.

Do Federal Confined Space Entry Requirements Apply to the Feds?

One last interesting factoid; the OSH Act originally did not apply to Federal agencies, meaning federal employers were not required by Congress to follow OSHA’s confined space entry standards; in fact, not even OSHA was required to follow their own confined space entry regulations! However, because of an executive order issued in 1980, federal agencies do now have limited coverage by OSHA standards, and must therefore comply with applicable OSHA confined space entry requirements (and all other applicable OSHA standards) during their entry operations.

Additional Information and Training on Confined Spaces

Hopefully this blog post helps clarify which OSHA confined space entry requirements apply to work being conducted at your site. Or, it may make you realize OSHA lacks jurisdiction over confined space entry operations at your worksite, and that you must figure out what alternate set of regulations may apply. You can learn more about this and other topics by taking one of the online confined space training courses available on our website.

In the next blog post (#5), we will address exactly who is responsible for making sure all permit-required confined spaces at the worksite are properly identified.

Final Note: Thanks for reading the blog. Please help spread the word about our confined space entry training blog by sending a link to the blog ( https://confinedspacetraining.net/confined-space-training-blog/ ) to others in your network who could benefit from this information.

Thanks, – Curtis

Filed Under: Permit Required Confined Spaces Tagged With: 1910.146, 1926 subpart AA, Application, EM385, Exemption, MSHA, osha, OSHA permit required confined space entry standard, Scope

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OSHA Alternate Entry Procedures for Permit-required Confined Spaces

How to Reclassify a Permit Required Space to a Non-permit Space Through Hazard Isolation

When it is Necessary to Reclassify Non-permit Confined Spaces as Permit-required Confined Spaces

OSHA Requirements for Signage and Notifications for Permit-required Confined Spaces

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