Construction Confined Space – It’s Happening!

This afternoon, OSHA issued their final rule for the construction confined space standard. The rule has been discussed in safety circles for YEARS, and some wondered if it would ever develop into something. Well, it’s happening! Last October, I prepared a webinar with an update on the standard, which at the time was stagnant. That presentation is on SlideShare and can give you a good digested version of the highlights:


There is no doubt that the standard is important and long overdue. OSHA estimates that the standard will prevent over 750 serious injuries every year. The rule will be published May 4, 2015 and will become effective August 3, 2015. For contractors who are in their busy season right now, this will represent a challenge to comply. OSHA stated in their press conference today that they are producing some compliance assistance materials and may conduct webinars.

This rule is especially near and dear to me as I got my start with a contractor that built wastewater and water treatment plants. If you’re looking for a dirty job, that was it. We worked closely with plant personnel to coordinate entries into piping systems that were part of much larger systems, including the drinking water supply to all of Southern California! I was part of some pretty amazing projects. It is contractors like that who will be hardest hit by the new standard. There are new acronyms and procedures to learn. In fact, there are now four types of confined space classification, not just the two we have become used to. The four new classifications are listed below in ascending order from “least” to most hazardous.

1. IHCS – Isolated Hazard Confined Space

This classification represents the lowest level hazard to employees. Compare this to the familiar non-permit required confined space (NPRCS). A space can be classified this way if all physical and atmospheric hazards are isolated.

2. CACS – Controlled Atmosphere Confined Space

A space can be classified this way if ventilation alone controls atmospheric hazards to safe levels. A space cannot be classified this way if a physical hazard is present that is not isolated. This classification was included as a protective yet cost-effective solution.

Documentation will be required for a CACS to note that physical hazards are isolated, ventilation alone is controlling atmospheric hazards, other identifying details of the space. The documentation should be posted at the entrance to the CACS.

3. PRCS – Permit Required Confined Space

A space is classified this way if ventilation alone will not reduce or maintain atmospheric hazards at a safe level. Hazards related to configuration and engulfment are other characteristics of a PRCS.

Access to a PRCS must be made physically difficult by means of barriers, high visibility physical restrictions at entrances and a retrieval system must be provided. Most of the familiar PRCS rules still apply.

4. CS-PRCS – Continuous System Permit Required Confined Space

A space classified this way is part of a larger confined space like a sewer system, that can’t be isolated from the larger space. This means there are IDLH conditions present due to potential release from the larger space that could overwhelm PPE or other controls. The CS-PRCS cannot be reclassified.


The CS-PRCS is obviously the mother of all confined space classifications. It represents a world that many have survived by good luck, not best practices. The regulation is going to force a thought process that many contractors do not currently go through. There is a possibility that OSHA will develop a Special Emphasis Program (SEP) to ensure contractors working in sewers and other larger confined space systems comply with the new standard. Only time will tell. But, you do not have much time as the standard’s effective date is 3 months away.

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