This article is the second in a three part series

In May 2015, OSHA published a new standard for the Construction Industry. The new 29 CFR 1926 Subpart AA now defines confined spaces in construction, and more importantly defines “permit required” confined spaces in construction. Part 1 of this series gave an overview of the new rule and discussed its effects on the industry related to specific requirements for project owners, general contractors and trade contractors. This article, which is part 2 of the series, will elaborate on the requirements for classifying confined spaces as permit-required and will discuss the three methods for entry into these spaces including the process for downgrading a previously identified permit-required space.  

The definition of a Permit Required Confined Space in construction is fairly similar to the General Industry Standard. The new 29 CFR 1926.1202 standard states that a permit space is any confined space having one or more of the following characteristics:

1. Contains or has a potential to contain a hazardous atmosphere
2. Contains a material that has the potential for engulfing an entrant
3. Has an internal configuration such that an entrant could be trapped or asphyxiated by inwardly converging walls or by a floor which slopes downward and tapers to a smaller cross-section
4. Contains any other recognized serious safety or health hazard

Where the construction standard begins to differ from the general industry standard is in how a space gets classified, and by whom. Since construction sites by nature involve an ever changing facility occupied by multiple employers (subcontractors), the standard assigns responsibilities for identifying and classifying confined spaces to several entities. This is explained in detail in Part 1 of this series, and summarized as follows:

1. The Host Employer and/or Controlling Contractor must identify all existing confined spaces prior to work commencing on a job site
2. They must designate each of these spaces as permit-required or non-permit spaces
3. Danger signs must be posted at each of these permit-required spaces and sub-contractors must be notified of their existence
4. All contractors / sub-contractors on site must determine if their work requires entry into one of these spaces and must take steps to prohibit its employees from entering if it is not part of their scope of work.
5. If a contractor’s work does require it to enter one of these spaces they become an Entry Contractor and they must have a competent person investigate the space and determine the hazards to develop a means of proper and safe entry
6. As a construction project progresses, new confined spaces may be constructed, requiring identification, marking and additional notifications

Once a confined space is designated as a permit-required space by the Host Employer, the Controlling Contractor or an Entry Contractor, entry must be controlled by a written permit program operated by the Entry Employer. Note that there are no exceptions to this rule. Once the “permit-required” label has been applied to a confined space, the rules of this new standard must be followed; i.e. there must be a written plan and permit document, and entry can only be made under one of the three scenarios described herein. Even reclassification, or downgrading a space to non-permit because hazards have been eliminated, requires actions to be documented and certified.

Method 1 – Standard Permit Entry

If the space contains serious safety or health hazards that cannot be eliminated or controlled so that it can be reclassified according to one of the two methods below, all of the rules for permit-required confined space entry must be followed. This is a time consuming and costly entry procedure that is meant to reflect the level of the hazards involved and is mandated to ensure the safety of the entrants. Just like the use of personal protective equipment (PPE) should be considered the last line of defense, the use of the permit entry procedure should be utilized only after consideration has been given to how hazards could be controlled or eliminated. Doing so reduces danger to entrants and may justify the reclassification of the space or the use of modified entry procedures described below.

There will be times when this type of full permit entry must be performed. A space that has a configuration that could cause an entrant to become trapped or a space that has the potential for an entrant to become engulfed are examples that will require a permit entry unless those physical attributes are altered. Other examples would include a space containing a hazardous atmosphere that cannot be controlled and requires the use of self-contained breathing gear, or spaces that contain hazardous moving or energized equipment that cannot be shut off and locked out. In addition, there are times when it is the actual work to be performed in the space that introduces the hazard. Entry into a space to perform welding, or work that requires the use of a cutting torch, would mandate the permit-required classification and all of the standard permit entry procedures would have to be followed; as would entrance into a utility vault by a qualified person to conduct work on energized circuits or equipment.  Other hazards to consider when classifying the space and planning the entry would include extreme heat or cold. Entry into a metal silo with outside temperatures of 110 degrees would certainly represent an additional hazard that would cause the space to be permit-required, while scheduling the same work at a time when the temperature is 60 degrees may eliminate that hazard.

A permit entry requires trained entrants, a dedicated attendant, an on-site entry supervisor and a means for immediate rescue should something go wrong. This complete procedure and its requirements will be discussed in full in the third article in this series.

Method 2 – Reclassification

Since construction work-sites are inherently evolving and conditions can change on a regular basis, the construction standard permits the reclassification or downgrading of a confined space if the following conditions are met:

• All hazards that were identified when the space was classified as permit-required must be either eliminated or isolated through engineering controls – this may include de-energizing and locking out circuits or equipment or blanking, blocking or misaligning pipes to eliminate engulfment hazards during entry
• The work that will be performed in the space cannot create any additional hazards, such as hot work or applying coatings that could result in a hazardous atmosphere
• There can be no actual atmospheric hazard present in the space
• There can be no potential for an atmospheric hazard to develop – note that if ventilation is required to control the atmosphere and make it safe, the space cannot be downgraded to a non-permit space; instead consider the alternate entry procedure #3 discussed herein

The requirement to control hazardous energy also introduces another program, known as Lock-Out / Tag-Out (LOTO), which has not previously been included in the Construction Industry Regulations. While the General Duty Clause has always mandated that contractors do something to control hazardous energy, the construction industry has not typically faced the more stringent and formal requirements of the General Industry’s LOTO program required under 29 CFR 1910.147 (General Industry Regulations). While this is probably still subject to future interpretation and enforcement guidelines, contractors are best advised to establish a written LOTO program that complies with the requirements contained in the General Industry Standards any time hazardous energy needs to be controlled in a confined space. In general, this includes developing a system where each exposed employee (in this case each entrant) has their own lock or tag applied at the point of control to ensure they are each protected.

In order to reclassify a space, a competent person representing the entry employer must verify that all of the above actions have been taken to render the space safe and justify its reclassification. While the standard is not specific on how to handle and maintain the paperwork under these conditions of reclassification, it does specifically state that the entry employer must provide written documentation of what was done to eliminate or control the previously identified hazards. It also states that the documentation must be dated and signed by the competent person who is certifying that the space is safe, and that the documentation must be made available to all entrants.

With the ever changing nature of construction sites and the typical multi-employer nature of most of these sites, it is advisable to approach any reclassification as temporary and specific to a single entry employer. In other words, develop a permit form that contains fields for documenting the reclassification. Approach the space first as permit-required until the hazards are eliminated or controlled. Document these actions on the permit, and then mark the permit form as “Temporarily Reclassified to Non-Permit Entry”. Include the date of entry and the certification by the competent person, and cancel the reclassification when entry operations are complete. Approaching the reclassification in this manner leaves a documented trail of the formal steps that were taken to render the space safe and justify its reclassification. Making the reclassification temporary and specific to each entry operation ensures that the space remains identified as hazardous and warns others not to enter the space. It also ensures that the permit-required designation stays in place when your entry operations are completed and you remove any temporary isolation or controls that were put in place.

Remember that all work performed to render the space safe must be conducted from outside the space, including any testing or inspection required to evaluate the space. If entry is required to perform this work, the permit-required entry procedures must be followed until the space is officially reclassified. Also keep in mind that using mechanical ventilation to maintain a safe atmosphere does not constitute an elimination of the hazard under this section and you cannot reclassify the space under this condition. Instead, evaluate the alternate entry procedure discussed next.

Method 3 – Elimination of All Hazards Except Atmospheric

The construction standard authorizes a third type of confined space entry that can be utilized when all hazards are eliminated or controlled, except for the possibility of hazardous atmospheric conditions. Remember, any confined space that “contains or has the potential to contain a hazardous atmosphere” must be designated as a permit-required space. The inclusion of the phrase “has the potential to contain” is significant in that it pulls in many different types of spaces that are subject to potential infiltration by gasses such as carbon monoxide (from generators, construction equipment or motor vehicles) and hydrogen sulfide (from adjacent sewer systems), and spaces that might be oxygen deficient (such as utility vaults). While the mere potential for a hazardous atmosphere mandates the classification of a space to permit-required, this third option can be utilize to minimize the impact to cost and productivity by following a written plan designed to increase safety and minimize risk.

The use of this third option requires the entry contractor to meet these requirements:

• All hazards except for the potential hazardous atmospheric conditions must be controlled or eliminated in the same manner as prescribed under the re-classification method
• The atmosphere inside the space must be properly tested to confirm safe conditions prior to making entry
• Continuous mechanical ventilation must be maintained during the entry operations
• The atmospheric conditions must be continuously monitored during entry operations
• Entry must be terminated if mechanical ventilation cannot maintain safe atmospheric conditions or if any other hazards are encountered during entry

Again, these actions, steps taken to eliminate hazards, and atmospheric test results must all be documented by the competent person representing the entry contractor and all of this information must be made available to everyone on the entry team; therefore it is best to approach this procedure in the same manner as described under the reclassification procedure, i.e. use the permit form to document the steps taken for a specific entry, note the entry as being done using the modified procedures of 29 CFR 1926.1293(e), and cancel the written permit at the conclusion of each entry operation. The benefits of this type of modified permit entry are that the requirements for maintaining a dedicated attendant and on-site stand-by rescue equipment and personnel are waived.

The use of this modified entry procedure mandates that the entry contractor utilize two specific types of equipment: a gas meter to test and continuously monitor air quality, and a mechanical ventilation fan with ducting as needed to ventilate the space.

The competent person will be required to use an appropriate gas meter to test the space without making entry. The exact method for conducting this test will vary depending on the space and its configuration, but affordable monitors can be purchased or rented to complete this requirement. A common type used to detect conditions anticipated on many job sites is a four gas meter that tests for oxygen, carbon monoxide, explosive gases and hydrogen sulfide. This covers the risks most commonly associated with the types of spaces that are entered on construction sites; however, additional tests may need to be performed for specific gasses if there is another known hazard. When checking atmospheric quality, it is important to remember several things:

1. Different gasses have different weights – you must check at least the top, bottom and middle of the space to ensure that you detect gasses that are lighter, heavier or the same weight as the air
2. Active sewer systems are not the only places that can contain hydrogen sulfide – this gas, which is commonly generated in sewer lines, can travel through the soil when it escapes through cracks or leaks in the system
3. Carbon monoxide is a colorless and odorless gas that is created by the exhaust of generators, equipment and cars – simply parking a running truck adjacent to the hatch of a utility vault can flood the space with deadly carbon monoxide
4. Oxygen in a space can be rapidly used up by things like organic growth (mold) or open flames

Remember that testing must be performed without making entry. Most equipment that is commonly used on construction sites today is very small and can be tethered and lowered into a space, attached to a pole to push it horizontally into a space, or it may come with a sampling pump and length of tubing that allows the meter to stay with you while you lower a sampling probe into the space. This is especially useful if the space may contain water that could damage the testing equipment.

Persons conducting this testing should be trained individuals who understand the use and limitations of the testing equipment, and who have knowledge about the space to be entered, the potential hazards, and the work to be performed inside. After testing the space and verifying safe entry conditions, the results of the tests are recorded on the permit form along with any other steps previously taken to render the space safe. When the entrants make entry into the space, they must bring the equipment with them to continuously monitor conditions in the space. When used properly, the gas meter will alarm to warn the entrants of changing conditions. Such an alarm would be an indication of deteriorating conditions and is a signal for immediate evacuation. Do not attempt to determine the cause while inside the space. Exit to safety and then asses the conditions from outside the space to determine what is happening.

It is not uncommon for the initial test values to indicate an unsafe atmosphere that requires mechanical ventilation to bring the space to a habitable condition. Again, ventilation equipment is readily available for sale or rent and consists of a forced air fan and length of air duct. Proper ventilation is typically performed by lowering the duct to the bottom of the space (or pushing it to the back of the space) and keeping the actual fan outside the space. The concept is to push fresh air from outside the space, into the bottom or far reaches of the space to displace the bad air and push it out. Mechanical ventilation for 30 minutes may be required to flood the space with breathable air, and the ventilation will need to continue for the duration of the entry to ensure adequate fresh air. To ensure proper test results and safe working conditions, stop the mechanical ventilation before taking new readings in the space. Verify through testing that the space can be brought to safe conditions prior to entry. You should be able to ventilate the space, turn off the ventilation, take new readings and verify safe and stable conditions prior to turning the ventilation back on and making entry. This ensures that entrants will not be immediately overcome if the ventilation fails.

Hazardous atmospheres cause the deaths of both untrained entrants and untrained rescuers every year – the standard contains the phrase “has the potential to contain” because it is so critical that we test these spaces. Numerous fatalities each year can be attributed to entering an untested space and then being overcome by a poisonous gas or lack of oxygen, and many more fatalities can be attributed to untrained, would-be rescuers who rush in to help the victim who is passed out. That is why advanced testing is mandatory prior to entry, and continuous monitoring is required while people are inside the space. If the gas monitor alarms, it is giving us notice that conditions are deteriorating and immediate evacuation is required. Likewise, if the space cannot be rendered safe and stable, entry under this modified procedure is not proper – use the full permit-required procedure and evaluate the need for self-contained breathing gear (SCBA).

Conclusions

At most work-sites, the Construction Industry has not been faced with a mandatory set of rules for classification of permit-required confined spaces, nor have we been faced with a mandatory set of rules for entry procedures. In many situations, work being performed by contractors on existing facilities has been classified as construction, and the General Industry rules for confined spaces have not been followed. Previous Construction Industry rules have only contained brief language requiring workers to be trained about the hazards of confined spaces. This has now all been changed with the publication of the new 29 CFR 1926 Subpart AA – Confined Spaces in Construction. There are now no longer any loopholes for employers whose employees enter confined spaces, regardless of whether you call it maintenance or construction. Any space that fits the definition of a confined space must be designated as permit or non-permit, and the appropriate procedures must be followed. For construction work performed on existing facilities, @OSHA has stated that a contractor will be deemed to be in compliance if they are following the new Construction Industry Regulations.

Attics, crawl spaces, vaults, manholes, concrete pier columns and elevator pits are all examples of confined spaces that are common on many construction sites. It is imperative that these spaces be identified and marked, and that all employees be trained to stay away from them unless they are a designated and trained entrant whose work requires entry. Confined spaces must be designated as permit-required or non-permit-required. Entry contractors must determine which of the three methods of entry described herein will be utilized to gain access to each permit-required confined space. Contractors will find that preplanning their work is essential to both making the work safer and working in a more productive manner. For the times were the hazards in confined spaces cannot be eliminated, the contractor will be required to develop and execute a full permit entry plan that includes on-site supervision, dedicated attendants, stand-by rescue methods and specialized training. This procedure is discussed in the third part of this thee part series.