Plaintiff’s Expert’s Role in Confined-Space, Flammable-Air Contaminant Cases

Reprinted with permission from the October 5, 2026 edition of The New York Law Journal © 2026 ALM Media Properties, LLC. All rights reserved. Further duplication without permission is prohibited, contact 877-257-3382 or reprints@alm.com.

Given the nature of many construction projects in New York City and its surrounding suburbs — sewer and manhole repairs, subway and utility tunneling, the cleaning or demolition of old fuel oil tanks, and the application of solvent-based coatings and adhesives in unventilated tanks, mechanical rooms, and elevator pits — workers could be injured working on a construction site in a confined space and in the presence of toxic, volatile, highly flammable, and potentially explosive materials. While the black-letter law of New York Labor Law §§ 200 and 241(6) may be straightforward, prevailing on negligence claims based on them in a confined-space, flammable-air contaminant case can be a different story.

When litigating such cases, plaintiffs’ attorneys must do more than simply appreciate the important role an expert can play in making their case. They need to understand exactly how their expert can do so.

A Primer on New York Labor Law Sections 200 and 241(6) and the New York State Industrial Code

Labor Law section 200 codifies the common-law duty imposed upon a site owner or general contractor to provide construction workers with a safe place to work. To be held liable under section 200, the owner or contractor must have either directed, supervised, or controlled the means and methods of the work causing the accident, or have had the authority to do so, including the ability to avoid or correct an unsafe condition. Section 200 applies to all locations where the Labor Law applies, and requires all work that is performed to be “so constructed, equipped, arranged, operated and conducted as to provide reasonable and adequate protection to the lives, health and safety” of employees.

Within the context of construction work, section 200 requires the site owner and general contractor to take reasonable measures for worker safety, to provide ‌a safe worksite, and to provide for and promote safe methods of performing the work. In addition, Labor Law 200 liability may be found where the accident proximately arose from a dangerous or defective worksite condition or hazard of which the owner or general contractor had actual or constructive notice.

In contrast to section 200’s requirement that a site owner or general contractor direct, supervise, or control the means and methods of the work causing an accident, Labor Law section 241(6) imposes a broad, non-delegable duty on owners, contractors, and their agents to provide reasonable and adequate protections and safety to workers, as specified in applicable New York State Industrial Code provisions, on sites where construction, excavation, or demolition work is being performed. Section 241(6) requires the work to be so constructed, shored, equipped, guarded, arranged, operated, and conducted as to provide such protection and safety to the persons employed at or frequenting construction, excavation, or demolition work sites.

Because this duty is non-delegable, owners, contractors, and their agents can be held liable for violating an Industrial Code provision even in the absence of their supervision or control over the particular work at issue. For there to be liability on an owner and contractor under section 241(6), the Industrial Code violation must have been a proximate cause of a worker’s injury.

The Labor Law places the onus on the owner and general contractor to comply with the Industrial Code’s provisions on the pain of being held liable for non-compliance. Compliance is customarily performed by the owner’s or contractor’s site safety officer, or site superintendent, or an individual with an equivalent function who walks the job site to identify and correct safety hazards before an accident occurs.

The Industrial Code provisions that provide a basis for a Labor Law 241(6) cause of action are found in Part 23 of the Industrial Code. Industrial Code Part 12 regulations, however, may inform a Labor Law section 241(6) violation if they are specifically incorporated by reference in Part 23 regulations, as they are in 12 NYCRR subsection 23-1.7(g). Relevant Industrial Code provisions in confined-space, flammable-air contaminant cases include, and provide in relevant part:

• 12 NYCRR § 12-1.4(b)(3): “No employer shall suffer or permit an employee to work in a room in which there exist dangerous air contaminants in a work atmosphere”.
• 12 NYCRR § 12-1.4(b)(4): “No employer shall suffer or permit dangerous air contaminants to accumulate or remain in any place or area subject to the provisions of this Part (rule)”.
• 12 NYCRR § 12-1.7(a): “All processes or operations using or generating air contaminants which constitute a fire or explosion hazard shall be protected from sources of accidental ignition”.
• 12 NYCRR § 12-1.7(b): “Concentrations of vapors which may be present in enclosed areas shall be deemed to be flammable when any such concentration exceeds 25 percent of the lower explosive level”.
• 12 NYCRR § 12-1.9(a)(1): “Confined spaces where dangerous air contaminants have been present, are present or could be introduced from potential sources shall not be entered by any person for any reason until the atmosphere of such confined spaces has been tested and found free of dangerous air contaminants. Any such confined space shall be continuously maintained free of dangerous air contaminants during any period of occupancy”.
• 12 NYCRR § 12-1.9(b)(5): “Prior to entering any confined space, the following steps shall be taken to insure the safety of the person entering: (5) Tests in the confined space for the presence of dangerous air contaminants or lack of sufficient oxygen, or both, where the threat of each condition exists shall be made by a designated person who is qualified to conduct such tests by training and experience”.
• 12 NYCRR 12-1.9(b)(6): “The mechanical ventilation system shall be so designed that the contaminants or contaminated air is transported to some safe location, without recirculation, and the replacement entry air does not contain dangerous air contaminants, but does contain sufficient oxygen . . . ”.
• 12 NYCRR § 12-1.9(d): “If the nature of the work to be performed produces or has the potential to produce dangerous air contaminants as specified in this Part (rule), continuous testing shall be performed. If such tests indicate evidence of dangerous air contaminants exceeding the concentrations listed in subpart 12-3 of this Part (rule) or in quantities greater than 25 percent of the lower explosive level, the occupants shall be ordered to evacuate the confined space immediately”.
• 12 NYCRR § 23-1.4(b)(14): “Air contaminants in quantities tending to injure the health of any person. Air contaminants in quantities greater than 25 percent of the lower explosive level of any substance, mixture or compound which they may form”.
• 12 NYCRR § 23-1.7(g): “The atmosphere of any unventilated confined area including but not limited to a . . . tank . . . where dangerous air contaminants may be present or where there may not be sufficient oxygen to support life . . . shall be subject to the other pertinent provisions of Industrial Code Part (rule) 12 and of Industrial Code Part (rule) 18 relating to ‘Exhaust Systems’”.
• 12 NYCRR § 23-2.8(a) defines a confined space as “a room, a portion of a room or an enclosure having no means of natural ventilation other than one entrance opening and which room, portion of a room or enclosure is of such dimensions that a painter is required to work inside such room, portion of a room or enclosure. Such confined space may be a tank . . . or a similarly enclosed space”.

How a Plaintiff's Expert Would Contribute to a Confined-Space, Flammable-Air Contaminant Case

In confined-space, flammable-air containment cases under Labor Law sections 200 and 241(6), plaintiffs’ counsel should strongly consider retaining an environmental, work safety, and fire expert to make as persuasive a case as possible to opposing counsel, insurer’s counsel, a neutral, and a factfinder. The expert’s main tasks will be to perform the necessary calculations and opine on whether the failure to provide the necessary safety devices and to ensure adherence to safe construction practices, as mandated by the Industrial Code, proximately caused a product’s vapors to exceed their lower ignition and explosion limits. When a flash fire occurred, the expert should opine on whether the vapors caused the fire.

Failing to control reasonably foreseeable ignition sources in the presence of the accumulation of flammable air contaminants creates a dangerous health condition as determined by 12 NYCRR section 23-l.4(b)(14). In that regard, a plaintiff’s expert should determine the implicated product’s vapors’ concentration sufficient to induce a fire and explosion and be able to opine whether the concentration violated the Industrial Code’s provisions concerning, among other things, purging the air in a confined space where the concentration of the volatile product’s airborne contaminants exceeds 25 percent of the lower explosive level of such air contaminants.

Any vapor-air contaminant concentration exceeding that amount would be considered flammable and require worker protection from sources of accidental ignition, such as providing adequate mechanical or local ventilation in the confined space to lower the airborne concentration. The expert would offer an opinion within a reasonable degree of certainty whether failing to exhaust highly flammable product vapors and provide necessary mechanical ventilation in a mechanically unventilated confined space would cause and permit concentrations of a volatile product’s vapors to exceed 25 percent of the lower explosive level, directly permitting air contaminants to exceed the product’s lower explosive limit, constituting a violation of the Industrial Code.

The expert would also render an opinion on the nature of the ignition or heat source, if identified by a fire department’s investigation, discovery, or otherwise. The expert would opine on whether electrical equipment, temporary construction lighting and wiring, or even electrical discharges and static electricity, depending on the product, could be the source of a fire and explosion once the product’s lower flammability and explosion limits are reached.

Further, the plaintiff’s expert would also be expected to express an opinion on whether failing to adhere to Industrial Code rules, including those referenced above, in the presence of a volatile and highly flammable product applied within an insufficiently ventilated confined space, was a proximate cause of the plaintiff’s injuries. Such a negligent failure, even by a subcontractor, would constitute a sufficient basis to cast the owner and general contractor as liable for violating Labor Law section 241(6).

A defendant’s failure to maintain the air contaminant levels below the level specified in 12 NYCRR section 23-1.4(b)(14), perform the required air testing before commencing work as required by 12 NYCRR section 23-1.7(g), and continuously during the ongoing work as mandated by 12 NYCRR section 12-1.9(d), would state a cause of action under section 241(6) if those violations proximately caused the plaintiff’s injuries, which in such a case are typically respiratory and burn injuries.

Additionally, because a plaintiff’s counsel could also bring a section 200 negligence claim based on specific facts pertaining to the confined workspace at issue in their client’s case, an expert’s assessments of whether accepted, safe, and customary construction industry practices were applied in the case will be essential in determining defendants’ departures therefrom and whether those departures were a proximate cause of the plaintiff’s injuries.

The Impact of a Knowledgeable and Credible Environmental, Work Safety, and Fire Expert

To increase their likelihood of prevailing in confined-space, flammable-air contaminant cases under Labor Law sections 200 and 241(6), plaintiffs’ attorneys should strongly consider retaining an environmental, work safety, and fire expert.

The New York Industrial Code offers several paths to victory for plaintiffs in these cases. A knowledgeable and credible environmental, work safety, and fire expert will increase the chances that a plaintiff and their counsel pursue the right one, given the facts of their case.