A comparison of carbon monoxide levels during the use of a multi-fuel camp stove

A Field Study of Carbon Monoxide Levels in Snow Caves During Short-Term Stove Use

INTRODUCTION

While the use of camping stoves in poorly ventilated areas is discouraged, the need to address dehydration challenges in harsh arctic conditions has led to their unconventional use inside snow caves for snow melting, subjecting occupants to unknown carbon monoxide (CO) levels. This study, located at sea level in northeastern Greenland, aimed to assess CO levels and dynamics during short cooking sessions in newly constructed emergency snow caves.

METHODS

In 5 snow caves, constructed according to the same design principles by 4 different individuals, a single MSR Whisperlite multifuel burner, primed with ethanol and burning white gas, was used to melt snow. CO concentrations were monitored every minute until all the snow in a 5-L pot was converted to water and CO levels returned to below 10 ppm.

RESULTS

A total of 16 experiments conducted showed that the priming phase generated the highest CO peaks, with a maximum of 120 ppm. Time-weighted averages ranged from 14 ppm to 67 ppm, with trial durations of 15 to 21 min. A single trial with a dirty burner resulted in up to a 10-fold increase in CO levels.

CONCLUSIONS

While single, short cooking sessions of less than 10 min burn time in newly constructed snow caves may be tolerated under specific conditions, the study highlighted substantial variation between caves and the importance of using clean burners, emphasizing the need for further research to gain a comprehensive understanding of CO exposure dynamics in snow caves.

Carbon Monoxide Levels Produced by Propane/Isobutane Canister Stoves inside a Tent

INTRODUCTION

Improper use of camp stoves in enclosed spaces has resulted in fatalities from carbon monoxide (CO) poisoning. Prior research has focused on the CO output of stoves burning white gas, unleaded gas, or kerosene. Stoves burning an isobutane/propane fuel have not been investigated and are the focus of this study.

METHODS

Three stoves utilizing isobutane/propane fuel were used to heat a pot of water inside a 3-season tent under controlled settings. Multiple runs with each stove were performed, and CO measurements, in parts per million (ppm), were recorded at 1-min intervals for a total of 15 min using a RAE Systems gas monitor. Data are reported as mean with SD. Repeated measures analysis of variance was utilized to examine changes over time. Statistical significance was set at P<0.05.

RESULTS

There was a statistically significant main effect of time and CO level, F (14, 168)=7.6, P<0.001. There was a statistically significant difference between-subjects effect of stove group F (2, 12)=8.6, P=0.005, indicating that CO levels were different depending on the stove. Tukey's post-hoc analyses revealed that stove A had the highest CO levels. The average level of stove A was statistically significantly higher than that of stove B and stove C, with a mean CO level difference of 79 ppm (95% CI, 3-156), P=0.043 and 117 ppm (95% CI, 40-194), P=0.004, respectively.

CONCLUSIONS

Stoves utilizing isobutane/propane fuel can produce unsafe CO levels and should not be used in enclosed spaces.

Effect of fuel type on carbon monoxide accumulation in tents of varied design

OBJECTIVE

The use of backpacking stoves in tents has been recognized to result in elevated carboxyhemoglobin levels and even death among tent inhabitants. A study was performed to evaluate carbon monoxide production occurring in varying tents with variable fuel types.

METHODS

Using a popular backpacking stove, both white gas and regular unleaded gasoline were used to heat a pot of water inside 2 tents of differing levels of weather resistance ("3-season tent" and "4-season tent") under controlled settings. A remote carbon monoxide sensor measured levels over a 20-minute period. Multiple 20-minute runs were performed with varying fuel and tent combinations to assess peak levels and rates of carbon monoxide production.

RESULTS

Mean peak carbon monoxide levels were obtained in the 3-season tent and 4-season tent when white gas was burned measuring 60.5 ppm (95% CI: 31.2 to 89.8) and 154.5 ppm (95% CI: 112.8 to 195.7; P = .002), respectively. The use of regular unleaded gasoline in the 3-season and 4-season tents resulted in mean peak carbon monoxide levels of 102.9 ppm (95% CI: 77.8 to 128.0) and 210.6 ppm (95% CI: 37.4 to 383.1; P = .06), respectively. Using regular unleaded gasoline resulted in significantly increased mean peak carbon monoxide levels compared with white gas in the 3-season tent (P = .006); however, the difference was not significant in the 4-season tent (P = .23).

CONCLUSIONS

The use of backpacking stoves in tents produces varying levels of carbon monoxide related to fuel type and tent styles. Efforts should continue to educate persons of the risk of carbon monoxide poisoning with the use of any stove while inside tents.

Study of physiological responses to acute carbon monoxide exposure with a human patient simulator

Human patient simulators are widely used to train health professionals and students in a clinical setting, but they also can be used to enhance physiology education in a laboratory setting. Our course incorporates the human patient simulator for experiential learning in which undergraduate university juniors and seniors are instructed to design, conduct, and present (orally and in written form) their project testing physiological adaptation to an extreme environment. This article is a student report on the physiological response to acute carbon monoxide exposure in a simulated healthy adult male and a coal miner and represents how 1) human patient simulators can be used in a nonclinical way for experiential hypothesis testing; 2) students can transition from traditional textbook learning to practical application of their knowledge; and 3) student-initiated group investigation drives critical thought. While the course instructors remain available for consultation throughout the project, the relatively unstructured framework of the assignment drives the students to create an experiment independently, troubleshoot problems, and interpret the results. The only stipulation of the project is that the students must generate an experiment that is physiologically realistic and that requires them to search out and incorporate appropriate data from primary scientific literature. In this context, the human patient simulator is a viable educational tool for teaching integrative physiology in a laboratory environment by bridging textual information with experiential investigation.