Providing a Solid Foundation

In many cases, our training is the first opportunity workers have had to use entry equipment and to understand the potential dangers they could encounter in a confined space.

Does the typical worker who enters confined spaces take time to read the OSHA regulations or their employer’s policy detailing entry procedures? Probably not more than once, anyway.

The tripod and winch module lets students conduct an equipment inspection and physically set up and take down a tripod and winch.Many state and municipal workers are not covered by OSHA regulations, and many of their employers do not have policies or procedures governing confined space entry. How do we persuade these workers to take charge of their own safety?

More than 13,000 American workers are injured annually in confined space accidents, 5,000 of them seriously.


Around 100 workers are killed in confined spaces each year in the United States. These workers leave behind countless family members.

-- Department of Health, NY

In each of these cases (fatalities) there was a lack of Recognition and Testing, Evaluation, and Monitoring prior to entry.


The Massachusetts Water Resources Authority (MWRA) provides wholesale water and sewer services to 2.5 million people and more than 5,500 businesses in 61 communities in eastern and central Massachusetts. We have OSHA-based policies and procedures, safety equipment, and an annual confined space entry training requirement. In addition to training MWRA employees, we offer seats in our one-day confined space entry classes to employees of our member communities and other state and federal agencies. Because of the lack of OSHA jurisdiction and a scarcity of local procedures, we try to reach students through offering practical procedures for safe entry and educating them about the potential consequences of not using safe work practices.

Workers in confined spaces can be at risk of serious injury or death resulting from asphyxiation, engulfment, electric shock, falls, heat, fire, explosion, or long-term illness.

-- Canadian Standards Association

"The victim may not have been properly trained or did not understand the hazards."


Fifty four percent of the people exposed to oxygen deficient conditions died.


Two thirds of all confined space fatalities occur among would-be rescuers.


Our teams of employee instructors are peer leaders with extensive experience in entering confined spaces and a strong belief in working safely. We note that our policy and procedure are based on the OSHA standard, but we do not give out copies unless requested or quote regulations in our class. We teach what a confined space is, what the potential dangers are, and how to use the proper equipment to detect hazards and enter safely.

Elements of the Training
In the first hour, instructors administer a 30-question pre-test that highlights what students will be learning during the course of the day. The pre-test is followed by a video and a review of definitions of a confined space, hazards, detecting hazards, completing a permit, and the roles and responsibilities of the entry team.

The class then breaks into four groups, and the rest of the training is primarily hands-on, consisting of four 50-minute modules: ventilation, air monitoring, tripod & winch set-up, and a suspended confined space entry from a raised platform with a utility hole built in. Student groups rotate through each module. The small group size (6-7) gives ample opportunity for individual hands-on access to the equipment.

In many cases, this training is the first opportunity workers have had to use entry equipment and to understand the potential dangers they could encounter in a confined space.

Many deaths in confined spaces occur because people who are attempting to rescue someone else are neither trained nor equipped to do so.

-- OSHA, Jan. 12, 2010

Breathing in a low oxygen situation is like trying to breathe under water without an air tank. The air just isn't there to breathe.

The ventilation module reviews the identification of conditions that require ventilation, situations that can't be safely ventilated, and the physical set-up of a blower and hoses. We also discuss field set-up considerations, such as the location of intake hoses, sizing equipment and calculating air turnover rates, effects of low or high oxygen levels, symptoms of oxygen deprivation, etc.

A respirator is fine for some hazards, but most respirators do not supply air where none exists.

Asphyxiation is the leading cause of death in confined spaces. Asphyxiations that have occurred in permit spaces have generally resulted from oxygen deficiency or from exposure to toxic atmospheres.


In a recent report, 65 percent of the confined space deaths were a result of an atmospheric hazard.


Lack of oxygen for as little as 4 minutes can result in brain damage.

-- MWRA test question

The tripod & winch module lets students conduct an equipment inspection and physically set up and take down a tripod and winch. We also use this time to try on harnesses and learn how to adjust them for the best fit and comfort. Instructors discuss the attendant's role in monitoring the entrant, watching for signs of distress, and their responsibility for deciding whether to terminate the entry.

A confined space attendant knows the hazards in the confined space, knows the behavioral effects of hazard exposure, maintains communication with the entrant, decides if and when to evacuate an entrant.

In most cases, when an unattached entrant collapses due to low oxygen, rescue personnel will not get them out before there is any chance of brain damage. An attached entrant can be winched out and removed from the hazardous atmosphere while rescue personnel are on the way.

"Unfortunately, this incident was a classic example of a multiple-fatality event where would-be rescuers are themselves overcome in their attempt to save the initial victim."

-- Kay Gee, OSHA's area director for Queens, Manhattan, and Brooklyn

In the air monitoring module, students practice hands-on fresh air calibration of gas monitors and learn about pump draw times for air samples, O2, LEL, and H2S, alarm settings, stratification of gases in a confined space, and step-by-step procedures for testing a confined space prior to opening a cover or entering. Sample meter readings are used to determine whether conditions are safe for entry or not.

The air may look safe and smell safe and still contain enough toxic contaminants to kill.

Fresh air calibration of a gas monitor should be done prior to each entry.

-- MWRA procedure

When fresh air calibrating a gas monitoring device, the Lower Explosive Limit (LEL) display should read 0% LEL.

In the entry module, each student dons a harness and is attached to a winch to be lowered by another student into a utility hole set in a 10-foot raised platform. Each student plays the role of entrant and attendant and entry supervisor, getting a feel for lowering and raising an entrant with a winch, what it feels like to be suspended, and learning why harness adjustments are critical before entry.

The standard entry crew under MWRA policy is a three person crew, although provision is made for two person crews when certain conditions apply. Instructors demonstrate how to remove an unresponsive entrant from tripod suspension. We suggest that a two person crew take along a temporary plywood or lightweight utility hole cover. When removing an unresponsive entrant from a utility hole, it is necessary to lower the individual to the ground to relieve harness stress while waiting for help. Wrestling a heavy cover (70 to 300 pounds) back into place adds the risk of hitting the entrant's legs or causing back injury to the attendant, rendering further assistance difficult at best.

"An entrant who has been suspended immobile for a length of time could suffer from 'Suspension Trauma.' "

"One of the workers was trying to repair a pump or clear a blockage in the sewer line yesterday when he was overcome by hydrogen sulfide fumes. . . . First one goes down and is overcome by gas and drops or falls, and the second one, looking down from above sees the first one, figures he can go down to rescue. Same thing happens to him, the third one same thing, and fourth one, same thing happens."

-- Douglas County (Wis.) Sheriff Tom Dalbec, November 2007

"This family has already paid an incalculable price with the loss of two of its loved ones. Nothing can restore their lives."

-- Robert Kulick, OSHA's regional administrator in New York

After rotating through the four modules, the students reconvene at the end of the class and take the 30-question post-test. These are the same questions as on the pre-test. Students who come to class with no prior training or actual experience with the equipment regularly show marked improvement from their pre-test scores. While our own employees who attend annually generally score higher on the pre-test, they also show incremental improvement in post-test scores, thereby validating the need for refresher training even for experienced workers.

Have we made an impression on students that attend the class? Will they work safer on the job? We can judge only by the fact that some of the non-MWRA students have been returning to class, and by their comments on the class evaluation forms.

Some comments from student evaluations (non-MWRA employees):

"Seeing the meters detecting the gases in the confined space. I never knew the other dangers."

"All of it was useful. Open discussion, video and hands-on was an ideal learning environment! One of the best courses I have attended in my career."

-- USAF bioenvironmental engineer

"I learned something at every station I attended."

"Setting up Tripod was useful, never used one before."

"I learned about Suspension trauma for the first time."

"My supervisor should attend this course."

"I personally thought the trainers covered everything in great detail."

"All areas were useful because it was my first class."

"It could save my life."

This article originally appeared in the August 2010 issue of Occupational Health & Safety.

About the Author

George Denhard is Manager of Training & Development for the Massachusetts Water Resources Authority in Boston, Mass. Prior to joining the MWRA, he spent eight years with the U.S. Department of Labor, Employment & Training Administration, and five years with the Bay State Skills Corporation overseeing and managing training programs. He has been coordinating the MWRA Confined Space Entry Training program since its inception in 1992.

Download Center

HTML - No Current Item Deck
  • Safety Management Software - Free Demo

    IndustrySafe Safety Software’s comprehensive suite of modules help organizations to record and manage incidents, inspections, hazards, behavior based safety observations, and much more. Improve safety with an easy to use tool for tracking, notifying and reporting on key safety data.

  • The Top 5 Safety and Technology Trends to Watch in 2020

    Get the latest on trends you can expect to hear more about in 2020, including continued growth of mobile safety applications, wearable technology, and smart PPE; autonomous vehicles; and increased adoption of international safety standard, ISO 45001.

  • Get the Ultimate Guide to OSHA Recordkeeping

    OSHA’s Form 300A posting deadline is February 1! Are you prepared? To help answer your key recordkeeping questions, IndustrySafe put together this guide with critical compliance information.

  • The 4 Stages of an Incident Investigation

    So, your workplace has just experienced an incident resulting in the injury or illness of a worker. Now what? OSHA recommends that you conduct investigations of workplace incidents using a four-step system.

  • Why Is Near Miss Reporting Important?

    A near miss is an accident that's waiting to happen. Learn how to investigate these close calls and prevent more serious incidents from occurring in the future.

  • Industry Safe
comments powered by Disqus

OH&S Digital Edition

  • OHS Magazine Digital Edition - November December 2019

    November / December 2019


      Redefining Compliance for the Gas Detection Buyer
      Don't Trip Over the Basics
      What to Look for in Head-to-Toe PPE Solutions
      Effective PPE for Flammable Dust
    View This Issue