F2165-06-Heat Stress Due to Thermal Protective Clothingindividual.utoronto.ca/Avi_S9/RFPB Heat Stress Due to Thermal... · ESC102F2165+06’ Heat’Stress’Due’to’Thermal’Protective’Clothing’

ESC102 F2165-‐06 Heat Stress Due to Thermal Protective Clothing

REQUEST FOR PROPOSAL

Heat Stress Due to Thermal Protective Clothing

March 2, 2013

F2165-‐06


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Abstract Heat stress is the most significant issue the firefighter community of Toronto faces. This problem arises when firefighters on duty wear bunker suits made from Thermal Protective Clothing (TPC), which causes them to overheat. Not only does this issue cause heat stroke, cardiovascular strain and heart attacks, but it decreases the efficiency of man power in the field and the oxygen supply of the Self-‐Contained Breathing Apparatus (SCBA).[18] Multiple studies have shown that coupled with hot environments and physical exertion, TPC causes dangerous levels of heat strain. In fact, the more effective TPC is at protecting the wearer from burns and chemical poisoning, the more burdensome it becomes because of low Total Heat Loss (THL).[2] THL is the property of TPC that measures the level of heat transfer through the material. The lower the THL, the higher the insulating property of the TPC and therefore the higher the resulting physiological strain. Action taken up to date has focused on rehabilitation instead of prevention. For example, several studies have compared active versus passive cooling methods to optimize heat stress reduction.[10][ 3] The best methods are currently available and being implemented in Toronto. The statistics, however, show while 50% of firefighter deaths were attributed to heart attacks in 2006, 46.5 % of them were in 2011, making the drop less than 5%.[23][13] Furthermore, Janos Csepreghi, an executive member of the Toronto Professional Firefighter’s Association, stated that heat stress is still today the leading cause of death in the community(Appendix D), which means rehabilitation is not effective enough and preventative techniques must now be researched. Consequently, a portable solution that prevents the physiological burden of wearing TPC without compromising the NFPA Performance Requirements (Appendix A) must be designed.[13]


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TABLE OF CONTENTS Abstract…………………………………………………………..………………………………………………………………………….2 1. Introduction……………………………………………………..…………………………………………………………..…………4 2. City-‐of-‐Toronto Firefighters …………………………………………………………..…………………………….…………..4 2.1. Firefighters as a Community….……………………………………………………………………….…………..4 2.2. Quality-‐of-‐Life Considerations……………………………………………………………………………………4 2.3. The Heat Stress Need..…………………………………………………………………….…………………………5 3. Philosophy of Engineering Design…………………………………………………………………………………………….5 3.1. Engineering Design Definition……………………………………………………………………………………5 3.2. The Bunker Suit Engineering Design Problem…………………………………………………..………...5 3.3. The Bunker Suit Engineering Design Process……………………………………………………………...6 4. Firefighter Bunker Suit Need……………………………………………………………………………………………………6 4.1. Consequences for Firefighter Quality-‐of-‐life………………………………………………………………..6 4.1.1. Short-‐term Consequences…………………………………………………………………..………..6 4.1.2. Long-‐term Consequences………………………………………………………………..…………...7 4.2. Specifics of the Bunker Suit……………………………………………………………………………………......7 4.3. Direction of the Manufacturers…………………………………………………………………………………..9 5. Considerations of Stakeholders………………………………………………………………………………………………11 5.1. GTA Firefighters………….…………………………………………………………………………………..………12 5.2. Bunker Gear Manufacturers ……………………………………..……………………………………..……....13 5.3. Government …………………………………………………………………………………………………..……….13 5.4. Workplace Safety and Insurance Board …………………………………………………………..……….13 5.5. Firefighter Unions / Associations……………………………………………..……………………..……….13 5.6. Emergency Services ………………………………………………………………………………………………..13 5.7. Home Owners and Businesses / Automobile Drivers ………………………………………………..14 6. Requirements of the Self-‐Cooling Bunker Suit…………………………………………………………………………14 6.1. High-‐Order Objectives……..……………………………………………………………………………….……...14 6.2. Detailed Requirements…………………………………………………………………………………………….14 6.3. Summary of Requirements…………….………………………………………………………………...………16 7. Exploration of Reference Designs…………………………………………………………………………………………...17 7.1. Apollo Shirt by the Ministry of Supply ……………………………………………………………..……….17 7.2. Cold Intravenous Saline Injection ……………………..……………………………………………..……….17 7.3. CoreControled Glove by Avacore….…………………………………………………………………..………18 Works Cited………………………………………………………………………………………………………………………………19 Appendix A………………………………………………………………………………………………………………………..……...21 Appendix B………………………………………………………………………………………………………………………..………22 Appendix C………………………………………………………………………………………………………………………..………23 Appendix D………………………………………………………………………………………………………………………..……...24 Appendix E………………………………………………………………………………………………………………………..………25 Appendix F………………………………………………………………………………………………………………………..………26 Appendix G………………………………………………………………………………………………………………………..………27 Appendix H………………………………………………………………………………………………………………………..…...…28


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1. Introduction The firefighters of Toronto are one of the city’s most vital communities and many issues associated with their work impede their quality of life. The purpose of this Request for Proposal is to frame the particular issue of heat stress as the engineering design problem of the bunker suit. These bunker suits make up the firefighters’ uniforms and are made from Thermal Protective Clothing (TPC). Studies show that the more effective TPC is at protecting the wearer from burns and chemical poisoning, the more of a physiological burden it becomes because of the low Total Heat Loss (THL) factor, which measures the amount of heat able to escape through the material.[2] The lower the THL of the TPC, the higher its insulating property and the higher the physiological strain on the wearer. This is the most detrimental factor to the quality of life of firefighters because it causes health conditions such as heat stroke, cardiovascular strain and heart attacks and as a result is the leading cause of death within their community. This Request for Proposal will begin by framing the problem and the community that it affects while explaining the engineering design philosophy used. Next, the stakeholders will be explored in order to impose and justify a set of guiding requirements for the solution providers. Finally several reference designs will be outlined and analyzed in terms of their potential contribution towards a solution. 2. City of Toronto Firefighters In order to frame the heat stress issue as an engineering design problem, we begin by defining three main sections of our chosen design space: the firefighters of Toronto. These three main sections are an overview of the Toronto firefighters as a community, their quality of life and the need that was found detrimental to that quality of life. 2.1. Firefighters as a Community Being in a community is “the condition of sharing or having certain attitudes or interests in common (e.g. a similarity or identity, joint ownership or liability)” and a community itself is a “group of people with a common characteristic or interest living together within a larger society”.[15] The firefighters of Toronto, which we define as the group of active professional and volunteering firefighters in the GTA sharing training expertise and working conditions, comprise the community that exhibits the bunker suit need. 2.2. Quality-‐of-‐Life Considerations Quality of life is the “notion of human welfare (well-‐being) measured by social indicators rather than by ‘quantitative’ measures of income and production.”[14] Individually, it is “personal satisfaction (or dissatisfaction) with the cultural or intellectual conditions under which a person lives (as distinct from material comfort).”[17] After talking to Janos Csepreghi (Appendix D), the most detrimental aspect to the quality of life to Toronto’s firefighters and the one that could most realistically be avoided was that of heat strain on duty.


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2.3. The Heat Stress Need Need is “a necessity arising from circumstances of a situation or case.”[11] The issue of heat stress is a need exhibited by the firefighting community that if solved, would improve the quality of life of its members. The circumstances in which firefighters must wear TPC and engage in physical exertion are unavoidable because these are fundamental to their job. The necessity that must be addressed is caused by the characteristics of the TPC to prevent sweat evaporation and encapsulate heat, which cause cardiovascular strain and heightened risk of heart attack. 3. Philosophy of Engineering Design The problem of the bunker suit was framed as an engineering design problem using a process based on a referenced definition of engineering design. We recommend that the solution providers use the following philosophy as guidance when developing a solution. 3.1. Engineering Design Definition Engineering design is said to be the “process of devising a system, component, or process to meet desired needs.” It is a process in which decision making is used, often in an iterative fashion to create a stated objective and then use “basic sciences, mathematics, and engineering sciences” to meet it optimally. Among the fundamental elements of the design process are the establishment of objectives and criteria, synthesis, analysis, construction, testing and evaluation.”[4] 3.2. The Bunker Suit Engineering Design Process We recognized that the decision making process mentioned in 3.1 could be broken down into three major steps: identifying the customer and their desired need, framing the need as an engineering design problem and solving this problem. The focus of this RFP is the first two steps, while the solution providers must solve the problem. In order to help us complete this process, we referred to flow charts illustrating the definition in 3.1(Appendix F).[4] 1. Identifying the Customer and their Desired Need: We chose Toronto’s volunteer and professional firefighters as our customers, or our target community, because of their extreme and unusual working conditions that adversely affect their quality of life. By pursuing preliminary research into their main needs, we narrowed down our focus to equipment issues since their workplace encompasses all of the GTA. Consequently we chose the issue of heat stress caused by the bunker suits as we found it to have the greatest detrimental impact. 2. Framing the Need as an Engineering Design Problem: To begin framing the heat stress need as an engineering design problem, we decided to use two main forms of research: online sources, and a member of the firefighting community. From this we


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were able to frame a set of specific requirements for our engineering problem as well as a thoroughly considered list of stakeholders and their stakes in the problem of the bunker suit. Online Sources: The combined use of newspaper articles, studies, research journals and our direct contact provided us with a rich perspective on the subject and all the evidence we needed frame a worthwhile engineering design problem. The metrics and criteria in the requirements for the design solution as well as the stakeholder considerations we incorporated were developed from these sources. Firefighter Community Contact: Mr. Csepreghi, an executive member of the TPFA, was informative, enthusiastic about the chosen need and willing to continue working with the solution providers. His first-‐hand experience further supported the large impact and relevance of the problem. Furthermore, he gave us an idea of the side effects that overheating could have on the co-‐ordination and efficiency of missions. 3.3. The Engineering Design Problem of the Bunker Suit The design problem: without compromising any of the NFPA Requirements (Appendix A) of the bunker suit, the solution providers must design a method of keeping the temperature of a firefighter on duty wearing full gear in expected working conditions below the heat stress range in order to eliminate the physiological burden associated with wearing TPC.[13]

4. Firefighter Bunker Suit Need There is supporting evidence that heat stress undergone by firefighters while wearing TPC is the most detrimental factor to their quality of life. The short-‐term and long-‐term consequences, the physical qualities of the bunker suit and the action taken up do date surrounding this issue all demonstrate its legitimacy. 4.1. Consequences for Firefighter Quality-‐of-‐Life This problem of the bunker suit affects firefighters in the short the long-‐term. Heat stress causes immediate health risks, organizational problems in the field and the decrease of manpower and equipment efficiency. Over time, heat stress results in health problems due to repetitive cardiovascular strain. 4.1.1. Short-‐term Consequences 1. Immediate heart attacks Extreme heat strain, stressful environments and physically demanding conditions are the main reasons that heart attacks are the largest killers of firefighters in North America.[23] Inexperienced and unfit volunteer firefighters are even more susceptible this, which is why their death rate due to


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heart attacks is higher than that of professional firefighters.[10] Finally, if any underlying heart condition or obesity is present, their heart attack risk rises exponentially.[20] 2. Organizational Issues According to Mr. Csepreghi,organizational confusion is the result of frequent cooling breaks taken by firefighters on duty.(Appendix D). This makes it another short-‐term issue caused by the problem of the bunker suit. Mr. Csepreghi explained firsthand accounts of firefighters who were lost track of because of their constant influx and out fluxes for cooling breaks (Appendix D). This problem has led to the deaths of firefighters, who have been trapped or have fallen unconscious while their location was unknown, 3. Efficiency Issues Efficiency issues also arise because firefighters have to take frequent cooling breaks. One efficiency issue is that of reduced manpower during critical times when fires are at their strongest and therefore the firefighters are even more overheated. The second is that of increased oxygen intake because of the increased stress on firefighter’s bodies, which leads to quickly depleted oxygen tanks, and more money having to be spent by the government and firefighter associations to accommodate for these issues. 4.1.2. Long-‐term Consequences In the long-‐term, heart attack risks are still prominent, even post retirement. The combination of repetitive heat stress over years of working in the field puts stress on the heart that causes permanent damage. Lyneth Wolski, the occupational physiologist said that “the combination of heat stress from temperatures of up to 200 Celcius and heavy-‐duty protective gear worn in a stressful occupation puts firefighters at risk of heart attacks.”[20] Finally, the organizational and efficiency issues become long-‐term problems as their impact is considered over time. 4.2. Specifics of the Bunker Suit There are two main attributes of bunker gear (see Fig.1) that causes a physiological burden to the wearer: the weight of the extra equipment, in particular that of the Self-‐Contained Breathing Apparatus (SCBA), and the properties of the Thermal Protective Clothing (TPC). The properties of TPC can be split into its weight and the intrinsic THL factor of the material. Also see Appendix H for the standard features of Morning Pride’s bunker suit that Toronto’s firefighters use.


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Figure 1: Morning Pride’s Bunker Suit[5] According to Mr.Csepreghi, the given equipment firefighters carry with them are necessary on duty. These may include tools, first aid supplies or other gear depending on the situation. Furthermore, the SCBA and the monitors associated with it are vital in order to supply and monitor oxygen in adverse environments (see Fig.2).

Figure 2: Toronto Firefighter wearing SCBA[6]


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Much “active research” has been done in order to optimize the protective versus burdensome relationship of TPC. Burden here refers to both the weight and the THL factor of the material.[2] In 2011, a study was conducted for the Textile Research Journal in order to analyze this ratio under low level heat exposures exactly like those firefighters face regularly. The study concluded that the physiological burden to the wearer inflicted by the TCP could not be reduced sufficiently without compromising the material’s ability to prevent burns.[2] As TPC becomes heavier, bulkier and thicker, the Intrinsic Thermal and Evaporative Resistances (Rcf and Ref) increase, which causes the THL to decrease and the resulting heat stress to rise to extremes, especially in hot and humid environments in which the human body relies primarily on sweating to cool down (Appendix B). Furthermore, this study was the first to consider the effects of stored energy as opposed to just using the regular TPP/RPP approach (Appendix C).[2] By so doing they proved that TCP absorbs the heat energy and dissipates it during the cooling process, which creates enough additional heat to burn the wearer in some cases. 4.3. Action Taken Up to Date Overview: Action has been taken regarding the problem of the bunker suit and although related firefighter heart attacks have diminished, they are still the leading cause of death in the community. In 2006, the US based National Fire Protection Association recorded that over 50 % of firefighters die of heart attacks.[23] Furthermore Lynneth Wolski, the occupational physiologist, stated that same year that she attributed 85 to 90 % of firefighter deaths to thermal stress coupled with the physical demands of the job.”[20] Since then, cooling methods have been evaluated, clothing changes have been made, codes have been modified and research has been gathered about monitoring devices in order to combat the problem. Studies evaluating cooling methods: 1. Toronto Fire Service In 2006, the Toronto Fire Service conducted a study on the “Management of Heat Stress for the Firefighter” comparing active versus passive cooling methods after heat strain suffered on duty.[10] Immersing one’s forearms into ice water was the most effective method and is implemented by Toronto’s firefighters according to Mr. Csepreghi (see Fig.3 below). Furthermore, the study also showed that wearing shorts beneath the bunker suit as opposed to the traditional pants proved to be more advantageous the longer the wearer was in TPC.[10]


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Figure 3: Kore Cooler Rehab Chair[7]

2. Fireground Rehab Evaluation (FIRE) Trial In 2010, the Fireground Rehab Evaluation (FIRE) Trial compared four marketed active cooling methods with the injection of 4°C degree saline solution in 24°C conditions.[3] None of the investigated active methods were particularly more effective than the injection because once the body was in a condition of heat stress, stabilization requires time regardless takes a long time regardless of the cooling method for it to stabilize again Clothing Changes: 1. Bunker Suit Manufacturers According to Mr. Cspreghi, Morning Pride, the bunker suit manufacturer that supplies Toronto’s Firefighters, terminated the implementation of elastic ankle-‐bands, designed to prevent water infiltration, in order to facilitate heat escape (Appendix D). In fact, his was the very reason why a colleague of Mr. Cspreghi’s suffered burns around the groin area as hot steam got into his suit. Code Modifications: 1. The NFPA The 2008 Edition of the NFPA Performance Requirements have updated so that the material must have a THL 450 W/m2 instead of the 2007 version of 205 W/m2 , which will allow for more heat and moisture transfer thereby allowing the body to cool to a greater extent. [13] Research Conducted in Order to Solve the Problem: 1. The University of Victoria and Tiny Transmitters The university conducted research and developed a small transmitter that could be swallowed to monitor core body temperature, heart pressure and blood pressure. It would send out signals through a chest monitor so firefighters under strain could be rescued. The monitor and transmitter cost 3058$ per set and were approved in January 2006 by Health Canada. [20]


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Conclusions: Despite all of these efforts over the half decade, 46.5 % of firefighter deaths were still attributed to heart attacks in 2011 because of this issue therefore the need to develop a method of cooling firefighters on the job legitimate and justified one. [23] Furthermore, there has been very little research done to prevent heat stress because the focus has primarily been on relieving it, which makes this design problem even more pertinent. 5. Considerations of Stakeholders When creating a design workspace, one of the most important factors to consider is the stakeholders and their stake in the engineering project. We recognize that certain stakeholders have a greater stake in the project, and we will attempt to rank them as reasonably as possible. The main types of stakeholders that we will consider in this project include the following: clients, regulators, users, the public and the environment. In the context of our problem, the public stake, we find, is significantly important because of the vital position of firefighters within our community (See Fig. 4).


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Figure 4: Tree Diagram of Stakeholders for the bunker suit engineering design problem for GTA firefighters. 5.1. GTA Firefighters Firefighters are the most important stakeholder for this engineering problem, as they play the role of our primary client. As our main client, we are trying to serve them by solving a problem and increasing their quality of life, in this case reducing their chance of heart attacks and improving their efficiency at work by directly integrating cooling into their bunker suit, so they don’t have to take frequent breaks.


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5.2. Bunker Gear Manufacturers Another important stakeholder and main client for us, because they will be the companies that will take our potential design to mass production. Having them as one of our main stakeholders implies that we must find a solution that economically feasible and can be produced in a short amount of time. 5.3. Government As firefighters are an important public resource and service, the government will have to take an important role when it comes to this engineering problem. All forms of government from the municipal level to the federal could arguably a stake in this project. Firstly, the ministry of health and ministry of labour (Workplace Health and Safety) could hold a stake, with the effects of overstraining on firefighters, increased hospitalization and causalities of firefighters. Other minor stakes can be held by the ministries of the environment and infrastructure as the shortage of man power in fire departments, affects the maintenance of infrastructure in the city as well as the control of certain fires that could be detrimental to the environment. 5.4. Workplace Safety and Insurance Board Within the Occupational Disease Policy and Research Branch of the WSIB, they investigate problems and risks involved in the workplace of all different professions. They work extensively with firefighter unions to address in adjudicating occupational disease claims and developing persuasive evidence that firefighters are exposed to greater health risks such as heart attack and cancer. This stakeholder definition could be expanded to other research organizations that have investigated the health risks involved with firefighting. 5.5. Firefighter Unions / Associations Our next stakeholders are the organizations that take this research and recommend certain codes and standards to protect firefighters. In our research process we have touched base with a member of the Toronto Professional Fire Fighter’s Association (TPFFA), to help us determine to get a first person perspective of the problem and to collect recommendations for the definition of the problem. Associations such as the National Fire Protection Association (NFPA), are also very important stakeholders as they are the stakeholders that play the regulator role with their annual publishing of codes. 5.6. Emergency Services Emergency Services also has a stake in the improvement of this health risk, as it will affect manpower at hand to respond to calls. As EMS and firefighters work as a cohesive unit, the more efficiently and quickly firefighters can extract injured for certain situations, EMS can be given a greater chance of keeping the alive and healing them in the long run. Finally, if firefighters are safer from potential health risks, EMS will be able to focus on treating public injuries as opposed to injuries within the firefighters.


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5.7 Home Owners and Businesses / Automobile Drivers Home owners, businesses and automobile drivers are a logical transition from the previous stakeholders, emergency services, as they are the indirect clients of engineering problem. The function of the firefighting community is to serve the overall community and keep them safe in case of critical emergencies. The less health risks (more manpower) and more efficient firefighters do their job, the more lives can be saved due to fires in the GTA, whether it be in a structure or a vehicle. 6. Requirements of the Design Solution 6.1. High-‐Order Objectives

• Design a solution that reduces the heat-‐related effects of wearing TPC and prevents its physiological burden.

• Integrate the solution into existing bunker gear. • Integrate ergonomic principles and human factors such as comfort, portability and safety. • The solution should meet the criteria described in section 6.2.

6.2. Detailed Requirements Detailed Objectives Design for Portability:

• Ease of carrying and/or carrying within the suit Design for Safety:

• Should maintain the protection against toxins that bunker suit provides

• Shouldn’t affect the protective layers that prevent burns Design for Comfort:

• Ease of movement and stress-‐free Design for Durability:

• Long-‐lasting, strong and easy to fix and maintain over time Criteria Effectiveness: -‐ how well the design solution can cool the firefighter and keep the firefighter’s body temperature at 98.2°F (36.8°C), which is the body’s optimal temperature[21] (metric: temperature in degrees Celsius; the more stable around 36.8°C, the better) Cost: -‐ total cost of implementing design solution (metric: cost in Canadian dollars; lower is better)


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Ease of use: -‐ the amount of training for the firefighters required to learn how to use the new design (metric: time; less is better) Durability: -‐ the length of time that the design solution will remain in operable condition (metrics: time and frequency of maintenance required; longer is better for time and less is better for frequency of maintenance required) Portability: -‐ how easy the device is for firefighters to carry (metrics: weight and volume; less is better for both) (other considerations: straps, buckles or other aspects of the device that make it easier to carry) -‐ level of physical comfort of firefighters when carrying the device (metric: feedback from professional firefighters; positive feedback is better). Safety: -‐ to what extent implementation of the device affects safety of firefighters, where safety here means the prevention of burns and the penetration of toxins (metric: number of burns and number of infections due to exposure to toxins; where less is better for both). Eco-‐friendly: -‐ weighing the harm done by manufacturing and disposing of the solution device (metric: recyclable; the more recyclable the better) Constraints Safety: Design solution must not impose any additional danger on firefighter. (Firefighters always find themselves in dangerous conditions; the purpose of the solution is improve their quality of life so it should not increase danger.) Impact on Firefighters’ Ability to do Their Job: Design solution must not significantly inhibit the movement of firefighters. Design solution must not reduce the response time of firefighter. (Firefighters’ judgment and ability to act is a life-‐or-‐death call so the solution should allow them to be more comfortable and therefore think clearer and act faster.) Effects on Other Parts of the Suit: Design solution must not compromise any other function of the suit. (The solution cannot, for example, compromise the suits ability to protect the user from toxins.) Existing Standards: The design solution must follow requirements specified in the NFPA 1999: Standard on Protective Clothing for Emergency Medical Operations (Appendix A).


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6.3. Summary of Requirements

Detailed Objectives

Explanation Constraints Criteria Metrics

Effectiveness The rate at which cooling takes place.

None. Quickens attainment of optimal temperature: 36.8°C.[21]

Time (less is better)

Design for Durability

Lastingness and ability to resist force

-‐ must not fail under usual conditions the firefighters encounter

Decreases maintenance required. Decreases failure of device under extreme conditions.

Maintenance and frequency (less is better)

Design for Safety

The condition of being protected against physical harm.

-‐ no burns -‐ no chemical penetration through suit -‐ must follow codes and standards required by NFPA

Decrease the number of burns. Decrease exposure to chemicals.

Safety: -‐ number of burns -‐ number of infections due to exposure to toxins -‐ meets NFPA (non-‐negotiable)

Design for Portability

The ability to carry the device while in duty or build it within the bunker suit.

-‐ must not impose any additional danger on carrier

Facilitate the ability to carry the device around.

Weight (less is better)

Cost The amount of money the solution is going to cost.

Mr. Cspreghi stated that raising money for safety is an easy task.

Reduce the amount spent on solution. (large-‐scale production)

Money (less is better)

Ease of use Firefighters must be trained to use new device.

None. Decrease training required by firefighters to learn how to use the new design.

Time (less is better) Feedback from professional firefighters (positive is better)

Eco-‐friendly Environmentally friendly.

None. Decrease harm to environment when in use and when disposed.

Recyclable (recyclable is better)


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7. Exploration of Reference Designs The wide variety of cooling mechanisms available that could serve as components in a solution to the design problem that demonstrate its wide solution space; however, these designs are meant to serve as examples and the designer is not limited to them when coming up with a solution. The examples mentioned below, each of which has advantages and disadvantages, include a temperature-‐regulating vest, using cold saline injections and a hand-‐cooling device. 7.1. Apollo Shirt by the Ministry of Supply [12] The Apollo shirt is a knit shirt made of a synthetic blend of phase change materials that help manage heat, moisture and odor and is not made with toxic chemical coatings like Formaldehyde. The most relevant portion of this design is the thermo-‐regulatory base layer (Appendix G) that firefighters can wear under their suit. Key Features of the Shirt:

1) Heat management “Apollo uses Phase-‐change Materials (PCMs) to pull heat away from your body and actually store it in the shirt -‐ like a battery.” This type of material is used commonly used in NASA space suits.

2) Moisture management “Your body naturally sweats throughout the day. Using an engineering-‐driven approach, our unique blend of fibers will wick moisture away from your body, keeping you dry -‐-‐ in the hottest or tensest of situations.”

3) Odor Management “Your skin releases oils and other materials, which leads to bacteria. Bacteria is the leading cause of odor. By using an anti-‐microbial coating, as well as Silver threads, the Apollo shirt takes care of pesky odors.”

4) Dynamic Motion. “By using tests like Strain Analysis and designing the shirt with your motion in mind, the Apollo shirt adapts to your movements -‐-‐ it stays tucked in all day, and moves with your body rather than against it.” The most relevant portion of this design is the thermo-‐regulatory base layer that has the features of the Apollo dress shirt but in the form that a firefighter can wear under their suit. 7.2. Cold Intravenous Saline Injection[3] Cold saline infusion was considered the passive method of cooling during the Fireground Rehab Trial, where methods of active versus passive cooling were compared to find the optimal method of rehabilitation for firefighters suffering from heat stress. It involves the circulation of cold (4°C) saline fluid through a firefighter’s circulation system.


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Key Features of the Cold Saline Infusion:

1) Discomfort Factor The process of receiving a cold saline injection when suffering from heat stress is largely uncomfortable, and the subjects of the Fireground Rehab Trial undergoing this “passive” method of cooling who were later re-‐introduced to a heated environment complained of intense discomfort in the upper extremities where the saline was injected. [Firegournd Rehab Trial]

2) Heat Dissipation During the 20 minute rehabilitation period, the cold saline infusion resulted in a core temperature drop of approximately 0.86±0.45°C drop, thus proving that cold saline infusion does reduce core body temperature. This is marginally the highest temperature reduction, with the next best being the active cooling method of arm-‐immersion in water, which has a core temperature drop of 0.83±0.30°C.[3] Although cold saline infusion did result in the highest drop of core temperature after the 20 minute rehabilitation period, the difference between this temperature drop versus the active methods (i.e. water-‐cooled vest, fan, arm/hand immersion) was minimal. 7.3. CoreControled Glove by Avacore[1][3] This device was used as an active cooling method for the Fireground Rehab Trial. It works by applying a slight vacuum distal to the wrist and has been marketed to the Toronto firefighters (Appendix G). Key Features of the Hand-‐Cooling Device:

1) Accelerates Blood Flow The CoreControl hand-‐cooling device accelerates blood flow “using a proprietary and scientific combination of carefully controlled temperature settings and slight vacuum. “

2) Speeds Up Natural Heat Dissipation Process The accelerated flow of blood is targeted at specialized blood vessels called arteriovenous anastomoses located in the palms. These blood vessels are close to the surface of the skin which causes heat to dissipate from the blood as it flows through the vessels. The accelerated flow of blood speeds up the natural heat dissipation process.

3) Effective Core Cooling Most cooling methods are ineffective at cooling the core often as a result of being applied at the skins surface and failing to penetrate the body’s insulating layers of tissue. However, this a very effective method for cooling the entire core of ones body as the cooled blood flows throughout the entire circulatory system. While the CoreControl Glove is effective at cooling the human body, it lacks portability and would impair a firefighter’s mobility if they were to carry it with them. It presents, however, an interesting cooling technology and if the device could be significantly reduced in size it may yield a viable solution.


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Works Cited [1] Avacore Technologies "Technology: How it works"[Online] Available: http://www.avacore.com/technology/how-‐it-‐works [Accessed 15 February 2013]. [2] Guowen Song, Stephen Paskaluk, Rohit Sati, Elizabeth M. Crown, J. Doug Dale, Mark Ackerman “Thermal Protective Performance of Protective Clothing used for Low Radiant Heat

Protection”. Textile Research Journal 81.3(2010). [3] David Hostler, "Comparison of Active Cooling Devices with Passive Cooling for Rehabilitation of

Firefighters Performing Exercise in Thermal Protective Clothing: A Report from the Fireground Rehab Evaluation (FIRE) Trial." Prehospital Emergency Care 14.3 300-‐9 Sep 2010

[4] Eric Salt, Robert Rothery. Design for Electrical and Computer Engineers: "CAPSTONE DESIGN 1 AND 2." Clarkson University. [Online] Available: http://claws.eng.ua.edu/attachments/127_2011%20-‐%20Lecture%202.pdf [Accessed 14 February 2013]. [5] Goliath2 Studios[Online] Available: http://www.goliath2.com/HW1/rearzoom.html (Bunker Suit Rear) Available: http://www.goliath2.com/HW1/frontzoom.html (Bunker Suit Front) [Accessed on March 2nd 2013] [6] Goliath2 Studios[Online] Available: http://www.goliath2.com/HW1/Morning%20Pride%20Gear.pdf [Accessed on March 2nd 2013] [7] Honeywell [Online] Available: http://www.honeywellfirstresponder.com/en-‐ US/Pages/Product.aspx?category=RehabChair&cat=HLS-‐HFRP&pid=KoreKooler [Accessed on March 2nd 2013] [8] Kickstarter [Online] Available:http://www.kickstarter.com/projects/1850124313/ministry-‐of-‐supply-‐the-‐ future-‐of-‐dress-‐shirts[Accessed on February 14th 2013] [9] McLellan, T. M., and G. A. Selkirk. "Heat Stress while Wearing Long Pants Or Shorts Under

Firefighting Protective Clothing." Ergonomics 47.1 75-‐90 (2004). [10] McLellan, Tom M., and Glen A. Selkirk. "The Management of Heat Stress for the Firefighter: A Review of Work Conducted on Behalf of the Toronto Fire Service." Industrial health 44.3 (2006) [11] Merriam-‐Webster Dictionary [Online] Available: http://www.merriam-‐webster.com/dictionary/community [Accessed on February 14 2013]


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[12] Ministry of Supply [Online] Available:http://ministryofsupply.com/atmos-‐base-‐layer-‐459.html[ Accessed on February 14 2013] [13] National Fire Protection Association "NFPA 1999: STANDARD ON PROTECTIVE CLOTHING FOR EMERGENCY MEDICAL OPERATIONS. Current Edition: 2013 " [Online] Available: http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=1 999&cookie_test=1 [Accessed 15 February 2013]. [14] OECD [Online] Available: http://stats.oecd.org/glossary/detail.asp?ID=2218 [Accessed on February 14th 2013] [15] Oxford English Dictionary [Online] Available:http://oxforddictionaries.com/definition/english/community?q=community [Accessed on February 14th 2013] [16] Patirop Chitrphiromsri and Andrey V. Kuznetsov. " Modeling Heat and Moisture Transport in

Firefighter Protective Clothing during Flash Fire Exposure." Heat and Mass Transfer 41.3,206-‐15,Jan 2005.

[17] Princeton Wordnet Search [Online] Available: http://wordnetweb.princeton.edu/perl/webwn?s=quality%20of%20life [Accessed on February 14 2013] [18] Selkirk, G. A., T. M. McLellan, and J. Wong. "Active Versus Passive Cooling during Work in Warm

Environments while Wearing Firefighting Protective Clothing." Journal of occupational and environmental hygiene 1.8 (2004): 521-‐31.

[19] Selkirk, G. A., and T. M. McLellan. "Physical Work Limits for Toronto Firefighters in Warm

Environments." Journal of occupational and environmental hygiene 1.4 (2004): 199-‐212. [20] �"Tiny Transmitters Save Firefighters." Toronto Star (2006) [21] "Toronto Fire Crews Put Out Four-‐Alarm Fire, have Trouble in Heat and Humidity." Canadian

Press NewsWire (2005) [22] Torvi, David A., and Chris M. J. Sawcyn. "Improving Heat Transfer Models of Air Gaps in Bench Top Tests of Thermal Protective Fabrics." Textile Research Journal 79.7 (2009) [23] U.S Fire Administration "Firefighter Fatalities Statistics and Reports"[Online] Available: http://apps.usfa.fema.gov/firefighter-‐fatalities/fatalityData/statistics [Accessed 15 February 2013].


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Appendix A:

National Fire Protection Association Performance Requirements.[13]


22

Appendix B:

Effect of fabric thickness on thermal resistance, evaporative resistance and total heat loss. [2]


23

Appendix C:

Comparison of the TPP/RPP approach and the stored energy approach.[2]


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Appendix D:

Summary of Meeting with Mr. Janos Csepreghi

The group met with the executive officer in Toronto Professional Firefighter’s Association, Janos Csepreghi. The basics about Toronto Fire services and the firefighters department were explained to the group. Among the topics of discussion were the instant managing systems and the bunker gear models.

Next, we asked about the research we had undertaken, which concluded that the main cause of death among firefighters still was heart attacks and Mr. Csepreghi confirmed this. He also mentioned that methods of active cooling, such as the Kore Kooler rehab chair that is used by Toronto firefighters in particular, are ineffective solutions to the problem. He then proceeded to talk about problems firefighters face on a daily basis. The most important problem was the ineffectiveness of methods used for active cooling and how this affects firefighter efficiency. Issues that were explained by Mr. Csepreghi included organizational problems that have resulted in the loss of firefighters on duty, discomfort associated with the temperature alarms, as well as the dangers caused by the absorption of toxins into the bunker gear.

Finally, we discussed the importance of involvement of firefighters in construction decisions (related to material used).


25

Appendix E

We chose to narrow our scope down to the problem of the overheating of firefighters within their bunker suits during missions and physical activity. This struck us as a major problem, as it is the main reason behind heart attack deaths in firefighters and by solving the problem, not only will we reduce health risks for firefighters, but we will also increase their efficiency to do their tasks and help others. When compared to other problems that were suggested during group discussion and our meeting with contacts in our chosen community, we found that it was the most feasible first-‐year Engineering Science problem and will have the clearest transition into an engineering problem. It also has the biggest direct impact to the quality of life and needs of firefighters, by reducing health risk involved with performing their professional activities. Other problems such as the organization of the dispatch of firefighters during missions will also be indirectly solved when having dealt with the chosen problem.


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Appendix F:

Representation of Engineering Design.[4]

Representation of the Preliminary Stages of Engineering Design.[4]


27

Appendix G:

Black Thermo Regulatory Base Layer[9]

The CoreControl Glove by Avacore[1]


28

Appendix H:

Standard Features of Morning Pride Turnout Gear[6]

Documents

F2165-06-Heat Stress Due to Thermal Protective Clothingindividual.utoronto.ca/Avi_S9/RFPB Heat Stress Due to Thermal... · ESC102F2165+06’ Heat’Stress’Due’to’Thermal’Protective’Clothing’