When it comes to rescue operations, readiness isn’t just important – it’s everything! Many years ago, when Roco began offering standby rescue services, we used these terms for describing the required rescue response mode – whether it was “Rescue Standby” or “Rescue Available.” This distinction isn’t just a matter of preference; it’s about matching the right response strategy to the potential severity of the hazard and consequences of exposure, especially in immediately dangerous to life or health (IDLH) environments. Let’s explore why “Rescue Standby” is essential for high-risk scenarios and even mandatory for IDLH conditions.

First of all, let’s define the two terms.

Rescue Available – The rescue team is trained, equipped, available and willing to respond in a timely manner. Team members are monitoring the entry and can mobilize quickly to the entry site. This level of readiness is sufficient for low-risk, non-IDLH environments where the identified hazards are less severe. While “Rescue Available” may meet compliance goals in some situations, it’s unsuitable for high-risk operations where delays can have severe consequences.

Rescue Standby – The rescue team is to be positioned at or near the entry site with all equipment pre-rigged and personnel ready for immediate action. It is required by OSHA 1910.134 Respiratory Protection standard to have standby personnel ready and equipped to enter if personnel are entering an IDLH atmosphere to perform confined space work. With IDLH environments, the level of preparedness shifts from being simply available to being fully staged and ready to perform without delay.

"This readiness level isn’t optional—it’s required by OSHA 1910.134 Respiratory when workers are in IDLH conditions." 

OSHA’s standard for Permit-Required Confined Spaces (29 CFR 1910.146) emphasizes the importance of a “timely response” for confined space emergencies. For example, OSHA 1910.146(k)(1) and (i) require an employer who designates rescue and emergency services to: Evaluate a prospective rescuer's ability to respond to a rescue summons in a timely manner, considering the hazard(s) identified;

“Timely” Note to paragraph (k)(1)(i):

What will be considered timely will vary according to the specific hazards involved in each entry. OSHA’s Non-Mandatory Appendix F contains examples of criteria which employers can use in evaluating prospective rescuers as required by paragraph (k)(1). Don’t let the use of “Non-Mandatory” confuse you. Employers must still fully comply with the requirements of the standard. Non-Mandatory Appendix F simply offers methods or examples for meeting the regulation.

Here is an example from Appendix F, Section A. Initial Evaluation:

1. What are the needs of the employer with regard to response time (time for the rescue service to receive notification, arrive at the scene, and set up and be ready for entry)? For example, if entry is to be made into an IDLH atmosphere, or into a space that can quickly develop into an IDLH atmosphere (if ventilation fails or for other reasons), the rescue team or service would need to be standing by at the permit space. On the other hand, if the danger to entrants is restricted to mechanical hazards that would cause injuries (e.g., broken bones, abrasions) a response time of 10 or 15 minutes might be adequate.

Keep in mind, in toxic and low oxygen atmospheres, as little as 60 seconds can change the patient's outcome dramatically. That critical minute could be the difference between a successful rescue and a body recovery.

"If entry is to be made into an IDLH atmosphere, the rescue team would need to be standing by at the permit space.”

Compliance and Application

Understanding these distinctions extends beyond the regulatory language. This means more than just having the right equipment; it requires the team to be mentally and physically prepared to respond without hesitation. For example, when respiratory hazards are present, standby teams are equipped with breathing equipment, typically a self-contained breathing apparatus (SCBA), or supplied air respirator (SAR), and positioned to intervene without delay.

Rescue systems are to be pre-rigged, and personnel are briefed on the hazards and rescue plans specific to the site. Rescue Standby aligns with Appendix F guidelines and ensures the fastest possible response when every second counts.

Choosing the Right Readiness Level 

While “Rescue Available” may suffice in low-risk, non-IDLH environments, confusing these two very different levels of response readiness can be fatal. For IDLH spaces, “Rescue Standby” is not just the safest option—it is the standard. Employers must assess their operations and ensure their rescue teams are meeting the proper level of preparation to comply with OSHA's timeliness requirements.

"Rescue Standby aligns with Appendix F guidelines and ensures the fastest possible response when every second counts.”

Critical Takeaways

The difference between “Rescue Available” and “Rescue Standby” is not just technical jargon – it’s potentially a life-or-death decision. In IDLH conditions, even a brief delay can be catastrophic. OSHA’s 1910.146 Appendix F outlines the critical importance of response times, emphasizing that being fully staged and ready isn’t optional – it’s mandatory. Ensuring your rescue team operates at the “Rescue Standby” level in high-risk environments is essential for compliance, but more importantly, it’s a critical strategy for the entry team’s safety. Be sure that your team is set up for success, especially when lives are on the line.

Key Points

• Rescue Levels: The level of preparedness chosen is based on the hazards present. "Rescue Standby" requires teams fully staged and ready; "Rescue Available" is suited for low-risk, non-IDLH spaces.

• Timely Response: IDLH conditions demand that a team be ready for 'immediate action" according to OSHA CFR 1910.134.

• Compliance: OSHA's CFR 1910.146 Appendix F helps us define terms and gives us specific ways to evaluate rescue teams.

REFERENCES:

Roco’s Confined Space Types Chart & Compliance Guide

Blog: Thursday, June 30, 2022 - Rescue Standby: Why It Makes Good Sense

OSHA 29 CFR 1910.146 - Permit-Required Confined Spaces 

OSHA 29 CFR 1910.134 - Respiratory Protection

Jacob Melancon, ASP is an Associate Safety Professional through the Board of Certified Safety Professionals and currently works as a Safety Professional and Rescue Crew Chief at Roco Rescue. He has served thousands of hours as Rescue Crew Chief for Roco’s CSRT Rescue Standby Services at industrial facilities across the nation. 

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Ventilating a confined space isn't just about flipping on a fan and calling it a day. There’s an art—and a bit of science—to getting it right. If you don’t, you could be putting yourself and your team at risk. Let's break down four common mistakes people make when ventilating confined spaces: short-circuiting, recirculation, inadequate CFM, and bending ductwork like it’s a contortionist’s routine.

1. Short Circuiting

We’re not talking about blowing a fuse here—this short circuit is all about airflow. Picture this: you set up your ventilation to push fresh air into a confined space, but instead of circulating throughout the area, the air takes a shortcut right out of the portal. The result? Only a fraction of the space is getting ventilated, potentially leaving atmospheric contaminants in the space or workers’ breathing zone.

To avoid this, don’t just place your ventilation gear down and hope for the best. position the intake and exhaust strategically—ideally, on opposite ends of the space. Make sure that fresh air travels through the entire space, hitting every nook and cranny, before it exits. If the space in question only has a single portal, ensure that the ductwork is long enough and configured in a way that allows for ventilation in the area that work is taking place. On a side note, longer ductwork can result in decreased overall CFM – check with your manufacturer for details.

Recirculating air might be great for your car’s A/C, but in confined spaces, it can be a fatal mistake. If the air you’re pulling out of the space ends up getting sucked back in, you’re just circulating the same contaminated air over and over again. While the space may feel like it is being ventilated, the contaminates never get diluted out since they are being reintroduced back into the space with each air change.

The fix? Make sure the intake of your ventilation system is positioned in an area that is pulling clean air into the space and ensure the exhaust air is vented far away from the intake. Keep the intake and exhaust well-separated to avoid creating this vicious cycle.

3. Inadequate Ventilation Flow Rates

CFM, or Cubic Feet per Minute, is ventilation’s way of saying “How much air am I actually moving here?” If you don’t have enough CFM, you’re not pushing out the bad air fast enough, and the space could stay hazardous longer than you’d like, or possibly, not control the hazard at all.

Before you set up, do the math. Figure out how much air you need to move based on the size of the space and the level of contaminants you’re dealing with. Too little CFM, and you’re not doing much good. There are multiple methods to calculate the CFM required for your space (I know, math…) however, there are online calculators that can assist with this if math isn’t your strong suit. The typical formula starts with determining the volume of the confined space in cubic feet and the deciding the number of air changes per hour (ACH) required by your organization. 

"While OSHA and ANSI don't recommend a specific number of air changes per hour, a general rule of thumb is around 7 ACH before beginning work. The American Conference of Governmental Industrial Hygienists (ACGIH) recommends 20 ACH when ventilating confined spaces". 

To calculate the CFM requirements, multiple the confined space volume by the air changes per hour and divide that number by 60.

Example:

CFM =  Volume of space (ft³) X Air Changes Per Hour / 60 minutes

CFM =  2500 ft³ X 20 ACH / 60 min

CFM =  50,000 / 60 min

CFM = 833 ft³/min

After you’ve figured out your minimum CFM requirements, you can determine your minimum purge time prior to entry. You can choose to manually calculate this, use an online calculator, or use a ventilation purge time chart like the one provided here. This chart is calibrated to provide a pre-entry purge time representative of 7 complete air changes.

If you're into doing math, the formula below can be used to calculate your pre-entry purge time.

Example: 

Purge Time = Volume of Space X Pre-Entry Air Changes / CFM

Purge Time =  2500 ft³  X 7 Air Changes / 833 ft³/min

Purge Time =  17,500 / 833 ft³/min

Purge Time = 21 minutes

Ever try to suck a thick milkshake through a crazy straw? That’s what too many bends in your ventilation ducts can do to your airflow. Every bend creates resistance, slowing down the air and reducing the overall effective CFM of your ventilation system.

To avoid this, keep your ducting as straight as possible. If you do need to make a turn, go for gradual curves instead of sharp bends. This keeps the air moving smoothly and ensures that you’re getting the ventilation you need where it’s needed most. As with any piece of equipment, check the manufacturer’s guidelines for specific information. While every manufacturer will have their own guidelines for their products, most manufacturers rate their products as a decrease of around 15% per 90-degree bend with a max of two 90-degree bends. Typically this information will be provided on the device itself as seen in the picture below.

Conclusion

Ventilating a confined space is more than just a box to check—it’s about creating a safe atmosphere to work and breath in, or at least controlling the hazards to a level that’s as low as reasonably practicable. By avoiding these common pitfalls, you’re not just moving air; you’re ensuring that it’s doing its job effectively. So next time you’re setting up ventilation, remember: keep the air flowing where it needs to go, and don’t let short circuits, recirculation, inadequate CFM, or ductwork disasters stand in your way. Proper ventilation is a breath of fresh air – literally…..

ONLINE REFERENCES:

ACGIH: Ventilation

OSHA 1910.146: Permit-Required Confined Spaces

ANSI Z117.1 - 2022: Safety Requirements for Entering Confined Spaces

Chris McGlynn, M.S., CSP is a Certified Safety Professional and Nationally Registered Paramedic who serves as the Director of Safety and VPP Coordinator for Roco Rescue. He currently serves as Director-at-Large on the VPPPA Region VI Board of Directors and Secretary of the American Society of Safety Professionals Region IV Board of Directors. Chris also represents ASSP on the ANSI Z117 Confined Space and Z390 Hydrogen Sulfide Training Standard Development Committees. He is also an active OSHA Special Government Employee within the Voluntary Protection Program and is currently working towards a Ph.D in Occupational Safety & Health through West Virginia University's Statler College of Engineering. 

Are you struggling to navigate the complexities of confined space classifications? If so, you may find our latest white paper useful. This detailed analysis offers clear, practical guidance on determining whether a confined space requires a permit or can be managed under alternate entry or reclassification procedures, simplifying compliance for anyone managing a permit-required confined space program.

This guide will improve your understanding of how to properly apply the (c)(5) and (c)(7) procedures, ensuring the highest safety standards at your site. You’ll gain insights into avoiding common pitfalls, such as the prohibited practice of combining C5 and C7, which can prevent costly mistakes and ensure adherence to OSHA regulations. The paper also includes a C5/C7 Quick Reference Guide, designed to provide quick answers and streamline your decision-making process.

This paper explains the terms and requirements of C5 and C7 with straightforward language and real-world examples. It provides actionable steps to help you classify and manage confined spaces safely and efficiently. Equip yourself with the knowledge to make informed decisions about confined space safety.

Interested in a workshop or consultation from Roco Rescue? Contact us at 800-647-7626 or info@rocorescue.com.

Enhance your confined space safety program with expert insights and practical solutions.

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Perhaps the most commonly confused topic in confined space entry that I hear out in the wild is the difference between the terms entry and bodily enter. And it makes sense because, at face value, these two things sound incredibly similar. However, when we dig a little deeper and put into context, we’ll find out that they have two entirely different meanings and applications. So, let’s dive in!

To set the stage, let’s do a quick overview of the three characteristics that define a confined space. OSHA says that a confined space is a space that:

• Has limited means of access and egress, and
• Is not designed for continuous human occupancy, and
• Is large enough to bodily enter and perform work.

Remember that the space must contain all three characteristics for it to be considered a confined space. Notice the 3rd bullet point – large enough to bodily enter and perform work. We must be able to physically fit our body into the space and perform the assigned task. Now, the use of the term bodily enter stops with the definition.

Next, let’s look at what defines an entry. OSHA says an entry has occurred when any part of the entrant’s body breaks the plane of an opening into a confined space. Notice that making entry into a confined space does not necessarily mean entering with the whole body. In fact, only reaching your arm into the opening of the confined space constitutes an entry.

"So, here’s the difference. The ability to bodily enter is one of the three characteristics that define a confined space, whereas the term entry is the action of breaking the plane with any part of the body – not necessarily the whole body."

At this point, you may be thinking this is nothing more than semantics; however, this is an incredibly important differentiation.

When we understand that making entry into a confined space does not have to involve entering with our entire body, we may realize that workers in our area may have been making a lot more confined space entries than we realized. I’ve heard on numerous occasions and even seen it firsthand, where a worker sticks their arm in to turn valves or pokes their head in for a quick peek at something without going through the permit-required confined space entry procedure. After all, it’ll only take a second!

The reason this is important, and why it’s more than just semantics, is that even though a worker may be only just sticking their arm or head into a space, they could still be exposed to the hazards inside of that space. In some cases, that could have some serious consequences! For example, there may be exposed and activated rotating equipment inside of the space; so, sticking your arm or hand in may result in you being less handy around the worksite than you used to be! Alternatively, atmospheric hazards don’t just magically stop becoming hazardous right at the plane of the opening. The immediate area around the opening of the space could likely contain hazardous atmospheres as well. Sticking your head in for a quick look could be a fatal mistake.

"The time you save isn’t worth your life."

Understanding the difference between the two terms is critical for ensuring the safety of workers in and around confined spaces. The difference between the two carries significant weight, not only in definition but also in practical application. Knowing that crossing the opening of a confined space, even with just a limb, constitutes an entry and potential exposure to serious safety and health hazards is a basic fundamental concept that all workers should be well informed. So, the next time you think – I’ll just reach in and turn that valve or take a quick look – slow down and think! The time you save isn’t worth your life.

ONLINE REFERENCES:

OSHA 1910.146 PRCS

Chris McGlynn, M.S., CSP is a Certified Safety Professional and Nationally Registered Paramedic who serves as the Director of Safety and VPP Coordinator for Roco Rescue. He currently serves as Director-at-Large on the VPPPA Region VI Board of Directors and is past President of the American Society of Safety Professionals Greater Baton Rouge Chapter. Chris also represents ASSP on the ANSI Z117 Confined Space and Z390 Hydrogen Sulfide Training Standard Development Committees. He is also an active OSHA Special Government Employee within the Voluntary Protection Program.

In confined space work, ensuring air quality is a top priority. With directives from OSHA and consensus recommendations from ANSI & NFPA, understanding the ins and outs of atmospheric monitoring is key. This article will briefly review what OSHA requires as well as what ANSI, NFPA and Roco recommend for practices that ensure worker safety remains the top priority in working in these challenging environments. While the OSHA General Industry standard allows for periodic monitoring and sets no exact timespan between testing – however, as a safer way, Roco recommends continuous air monitoring any time workers are in the space.

OSHA 1910.146 refers to testing the internal atmosphere before an employee enters the space and testing as necessary to maintain acceptable entry conditions. Testing should be based on the hazard assessment for a given space as well as how rapidly those hazards could cause a change in the atmosphere, which may require additional action for safe entry.

OSHA’s Confined Spaces in Construction (1926-Subpart AA) also references monitoring frequency. It states continuous monitoring is required unless periodic monitoring is sufficient to ensure entry conditions are maintained, or continuous monitoring is not commercially available.

Note: Also take into consideration any previous work activities that may have introduced atmospheric hazards into the space as well as any known history of hazardous atmospheric conditions.

"Roco strongly encourages continuous monitoring while workers are inside a permit-required confined space."

Looking at best practice consensus standards, ANSI Z117 advocates for continuous monitoring in situations when a worker is present in a space where atmospheric conditions have the potential to change.

The national consensus standard, NFPA 350 Guide for Safe Confined Space Entry and Work 2022, also generally refers to “continuous air monitoring” when possible. Here’s a quote from NFPA 350, Section 7.13.1 (www.nfpa.org), Continuous Atmospheric Monitoring, “Atmospheric conditions can change quickly or gradually over time; without continuous atmospheric monitoring, air contaminants may increase, or the oxygen percentage may decrease or increase, creating dangerous confined space atmospheric conditions.” NFPA adds, “Entrants, Attendants, and other personnel may be unaware of changing conditions if the air quality was only initially monitored and determined to be acceptable. The atmosphere within and outside the confined space should be monitored continuously to ensure continued safe working conditions.”

PRE-ENTRY TESTING

Although OSHA does not define a specific timeline to conduct pre-entry monitoring, Roco uses as a guideline that a “baseline test” is to be conducted approximately 30 minutes prior to the entry and then again immediately prior to entry. If ventilation is being used as a control measure for atmospheric hazards, initial atmospheric monitoring should be conducted without ventilation to establish a baseline atmosphere.

A comparison of these readings could indicate that atmospheric changes have occurred inside the space. If a space has been vacated for a period of time, it is recommended that similar baseline testing be repeated. This is critical as it may reveal the presence of previously unrecognized or unanticipated atmospheric hazards.

Again, confined space work is inherently hazardous – and atmospheric hazards are a leading cause of fatalities. Do everything you can to keep your people safe. Don’t let your guard down even for a minute!

Additional Resources: 

Frequently Asked Questions: OSHA PRCS Standard Clarification 

How much periodic testing is required?

The frequency of testing depends on the nature of the permit space and the results of the initial testing performed under paragraph (c)(5)(ii)(c). The requirement in paragraph (c)(5)(ii)(F) for periodic testing as necessary to ensure the space is maintained within the limits of the acceptable entry conditions is critical. OSHA believes that all permit space atmospheres are dynamic due to variables such as temperature, pressure, physical characteristics of the material posing the atmospheric hazard, variable efficiency of ventilation equipment and air delivery system, etc. The employer will have to determine and document on an individual permit space basis what the frequency of testing will be and under what conditions the verification testing will be done.
 
What does testing or monitoring "as necessary" mean as required by 1910.146(d)(5)(ii) to decide if the acceptable entry conditions are being maintained?

The standard does not have specific frequency rates because of the performance-oriented nature of the standard and the unique hazards of each permit space. However, there will always be, to some degree, testing or monitoring during entry operations which is reflective of the atmospheric hazard.

Some of the factors that affect frequency are:

* Results of test allowing entry.
* The regularity of entry (daily, weekly, or monthly).
* The uniformity of the permit space (the extent to which the configuration, use, and contents vary).
* The documented history of previous monitoring activities.
* Knowledge of the hazards which affect the permit space as well as the historical experience gained from monitoring results of previous entries.

Knowledge and recorded data gained from successive entries (such as ventilation required to maintain acceptable entry conditions) may be used to document changes in the frequency of monitoring.

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