OSHA: Confined Spaces and HAZWOPER

How can a hazardous condition or environment become even more hazardous? An example of this would be looking at two popular Occupational Safety and Health Administration (OSHA) standards, Confined Space and HAZWOPER. Each standard addresses the unique hazards and employer requirements in order to protect exposed workers.

OSHA outlines employer compliance requirements regarding confined spaces within their General Industry regulation 29 CFR 1910.146, Permit-Required Confined Spaces and Construction regulation 29 CFR 1926.1200 (Subpart AA) Confined Spaces in Construction.There are also Maritime applications.

OSHA also outlines employer compliance requirements regarding Hazardous Waste Operations and Emergency Response (HAZWOPER) within 29 CFR 1910.120.

Confined spaces are commonly found on HAZWOPER sites. So, for employers engaged in hazardous waste, emergency response, and cleanup operations involving hazardous substances, effective training, preparedness, and management of emergency responses should include confined space hazards. The presence and inherent dangers of confined spaces should always be noted during the site characterization and analysis phase of a HAZWOPER site safety and health plan, with specific reference to pre-entry briefings. All personnel involved shall be given a briefing before operations commence. See Appendix D, Confined Space Pre-Entry Checklist.

Also, if you consult Appendix E of the OSHA HAZWOPER standard, Training Curriculum Guidelines, Suggested Training Curriculum Guidelines, it reads as follows:

The following training curriculum guidelines are for those operations specifically identified in 29 CFR 1910.120 as requiring training. Issues such as qualifications of instructors, training certification, and similar criteria appropriate to all categories of operations addressed in 1910.120 have been covered in the preceding section and are not re-addressed in each of the generic guidelines. Basic core requirements for training programs that are addressed include:

1. General Hazardous Waste Operations.

      (5) Review and knowledge of confined space entry procedures in 29 CFR 1910.146.

2. RCRA Operations—treatment, storage, and disposal facilities.

3. Emergency Response.


With regard to HAZWOPER’s application, and in reference to a previously published blog, let’s go over some important confined space criteria. The Construction standard was officially introduced in 2015, in harmonization with the General Industry standard. As such, both standards should be consulted for compliance purposes.

From an OSHA definition standpoint, it’s critical to know the difference between a confined space and a permit-required confined space:

Confined Space

A confined space:

  • Is large enough and so configured that an employee can bodily enter it.
  • Has limited or restricted means for entry and exit.
  • Is not designed for continuous employee occupancy.

Examples of confined spaces include tanks, vessels, silos, storage bins, vaults, hoppers, and pits.

Permit-Required Confined SpaceConfined Space

A permit-required confined space (permit space) is a confined space that has one or more of the following characteristics:

  • Contains or has a potential to contain a hazardous atmosphere.
  • Contains a material that has the potential for engulfing an entrant.
  • 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.
  • Contains any other recognized serious safety or health hazard, such as unguarded machinery, exposed live wires, or cold/heat stress.

When it comes to permit-required confined spaces, OSHA makes it clear that the employer develops and implements a written program, as detailed in section 29 CFR 1910.146(c)(4). A permit-required confined space program is defined as the employer's overall program for controlling, and, where appropriate, for protecting employees from permit space hazards and for regulating employee entry into permit spaces. The contents of the permit shall be communicated to all employees of the host employer and to contractors involved in the operation and be conspicuously posted near the work location.

See Appendix C, Examples of Permit-required Confined Space Programs for more information.


HAZWOPER Conditions

With additional emphasis to HAZWOPER conditions, consider the following elements of an effective confined space entry program regarding entrants, attendants (or monitors), supervisors and rescue/emergency personnel:


All personnel need to be aware of confined spaces and their associated hazards. Confined spaces are not always marked with signs and warnings. Identification may be aided with the use of Appendix A, Permit-Required Confined Space Decision Flow Chart.


Evaluation of Hazards.

Confined spaces should be tested prior to entry and continuously during operations by trained qualified individuals using suitable instruments. Confined spaces may contain a variety of hazards, such an oxygen deficient or enriched atmosphere and the presence of flammable, explosive, or toxic gases, vapors, or dusts. More information can be found within Appendix B, Procedures for Atmospheric Testing.


Control of Hazards.

Certain procedures and precautions are required to allow for safe entry and may be controlled through engineering and safe work practices. An example would be utilizing a blower to continuously ventilate the confined space with fresh air while workers are in the confined space and implementing appropriate respiratory protection equipment and measures for workers.



An effective means of communication between workers inside a confined space and the safety attendant/monitor must be used whenever conditions in the space require use of respirators or whenever entrants are out of sight of the safety attendant at any time. It is important that the communication system be tested before each use, and frequently thereafter, to ensure that it is working properly.



All personnel working in or around confined spaces shall receive initial and ongoing training to ensure continued competence. Training shall be provided for all host employer and contractor personnel associated with confined space entry operations and relative to their specific role and responsibilities. Training shall include criteria such as recognition and control of hazards, safe entry and emergency rescue procedures, and Personal Protective Equipment (PPE).


Emergency Rescue.

No program is complete without emergency rescue procedures and associated personnel. Entrants and attendants of confined spaces shall be properly trained in the proper use of safety and rescue equipment and emergency rescue procedures. As a guide, employers should consult Appendix F, Rescue Team or Rescue Service Evaluation Criteria.


For more information, OSHA has published an informative Confined Spaces Safety and Health Topic site.