Featured Topic

• Shift Food Fire Camp Trial
• Risk Factors and Stress: Incident Management Teams
• Bacteria and Fungi in Personal Drinking Systems
• Purification of Personal Drinking Systems

Research

This section reviews project-related field studies of wildland firefighters during the 2007 fire season. The studies were conducted by researchers and graduate students from the University of Montana Human Performance Laboratory, in cooperation with MTDC and the U.S. Army Research Institute for Environmental Medicine, with support from the National Wildfire Coordinating Group.

Shift Food Fire Camp Trial

Past UM-MTDC research has shown that eating small items throughout the day (shift food) rather than just eating at lunch enhanced work output before lunch and late in the shift. Total work output increased by 15 to 20 percent. Firefighters also preferred shift food to sack lunches during recent studies. Shift food cost less than standard sack lunches during those studies.

The 2007 study evaluated the use of shift food for wildland firefighters, with emphasis on implementing the program in a fire camp, the caterer's response, overall satisfaction with shift food, and the role of educational materials in changing the way firefighters eat during the workday.

The Big Sky Mobile Catering Corp. provided shift food at the Sawmill Complex and Jocko Lakes fire camps during the 2007 fire season. The shift food included smaller food items (50 to 300 kilocalories) served on a rotating menu. Bilingual educational materials provided in the dining tents included information on the shift food, the benefits of eating some food every hour or two, and the results of past studies. The shift food was served to firefighters for 5 days at the Sawmill Complex and for 6 days at Jocko Lakes. Satisfaction surveys were administered on the last day of each experimental trial.

Combined survey data showed that 46 percent of the respondents preferred the shift food, 31 percent preferred the traditional sack lunch, 17.8 percent preferred neither, and 4.9 percent preferred both (see figure below).

On average, respondents gave shift food a score of above 5.0 (scale 1 to 10, where 1 = strongly disagree and 10 = strongly agree) for convenience to carry (6.8), convenience to eat (6.8), ability to work (5.2), variety (6.5), taste (6.0), appearance (5.8), energy (5.6), and overall satisfaction (5.9). Firefighters preferred shift food based on its convenience, their ability to do work, their energy, and their overall satisfaction. Firefighters wanted additional food items in the shift food.

Food preferences during a study at two
Montana fire camps during 2007.

In general, shift food was well received. However, only 34 percent of the respondents reported reading the educational materials and consuming their food every 1 to 2 hours as recommended. Further anecdotal evidence suggests that firefighters need more information on nutrition and work performance. We recommend using the MTDC nutrition education program "Eating for Health and Performance: The Wildland Firefighter" (Cox and Sharkey 2007).

The respondents' overall satisfaction (5.9) with the shift food was lower than in previous trials, where firefighters selected their own food items from bins. To simplify the process for the caterer during this study, the shift food items were packaged by the caterer. The cost of high-calorie shift food ($17.91) was higher than the sack lunch ($14.85) and the low-calorie shift food ($11.29).

The UM-MTDC research team recommends that the caterers, contract personnel, and specialists at MTDC and the University of Montana collaborate to improve menus, contract language, and educational materials. In the future, the revised shift food system should be evaluated using several caterers in a number of fire camps.

Shift Food Fire Camp Trial. N. Plante and S. Gaskill, University of Montana; B. Sharkey, MTDC.

Conducted under terms of a memorandum of understanding between MTDC and the University of Montana Human Performance Laboratory.

Risk Factors and Stress: Incident Management Teams

Coronary artery disease is the leading cause of death in the United States. A 2006 survey of 66 incident management team members (Wildland Firefighter Health & Safety Report No. 11, 2007) showed that they had an average of 2.6 coronary artery disease risk factors. Physical inactivity and poor nutrition are two risk factors for coronary artery disease that are within an individual's control and can influence other risk factors, such as high blood pressure, high cholesterol, obesity, and diabetes.

The 2007 study discussed here evaluated the health status, activity levels, and cardiovascular risk factors of incident management team members during the 2007 fire season. Subjects were asked to complete a health history and risk factor questionnaire. After the survey was completed, their height, weight, resting heart rate, and resting blood pressure were recorded. Subjects completed a bicycle test to estimate maximal oxygen consumption (VO2 max). A blood draw was scheduled before breakfast the following morning for glucose and lipid panel analysis. Finally, subjects were asked to assess the stress associated with their team position.

Fifty-six team members served as subjects (38 males and 18 females). Their average age was 49.5. Overall, the team members mirrored national demographics in terms of coronary artery disease risk factors relative to their age, with an average of 2.8 risk factors—57 percent were overweight, 16 percent were obese, 21 percent had hypertension, 43 percent had low VO2 max values during the bicycle test, and 62 percent had a family history of heart disease. Additionally, 14 percent had high blood glucose levels, 18 percent had high triglycerides, 9 percent had low HDLs, 20 percent had high LDLs, and 43 percent had high cholesterol. Seventeen respondents (30 percent) said they had above average or severe stress in their position on the team. These data indicate that team members are at risk for coronary artery disease and demonstrate the need for stress reduction, both at fire camp and back at home. The authors recommend further study of job-related stress and its impact on coronary artery disease risk factors, overall health, and job performance.

Risk factors and stress: incident management teams. E. Lieberg, S. Gaskill, and C. Palmer, University of Montana; B. Sharkey, MTDC. Supported by MTDC.

Bacteria and Fungi in Personal Drinking Systems

This study surveyed bacteria, molds, and yeasts in firefighters' personal drinking systems. Personal drinking systems include water bottles and bladders with drinking tubes. Samples were collected from 15 personal drinking systems by taking samples of the water and swabbing the inside of the systems. Several different culture media were used to grow a variety of organisms. Firefighters were asked to complete a short questionnaire about their personal drinking system (how long they had used it, when they last cleaned it, and whether they added sport drink to the water).

High concentrations of molds and yeasts (opportunistic pathogens) were discovered inside several systems. Legionella-like bacteria (Legionella causes Legionnaires' disease) were detected in one water bottle and in a drinking tube. Most systems were over a year old and had never been cleaned (table 3).

Table 3—Microbiological investigation of personal drinking systems used by wildland firefighters. Camp crud is the way firefighters describe upper respiratory illnesses that pass through fire camps.

Water container	Seasons used	Time since last cleaning	Addition of drink mix	Mold present	Yeasts present	Sick in the last month
Sipping system	1	Never	No	Yes	Yes	No
Sipping system	Unknown	Never	No	Yes	Yes	Camp crud
Sipping system	1	Never	Yes	Yes	Yes	Camp crud
Sipping system	1	Never	No	Yes	Yes	Sinus infection
Water bottle	5	Never	No	Yes	Yes	No
Water bottle	1	Never	No	Yes	Yes	Camp crud
Water bottle	Unknown	Never	No	Yes	Yes	Camp crud
Water bottle	1	Never	No	Yes	Yes	No
Water bottle	1	Never	Yes	Yes	Yes	No
Water bottle	1	Never	No	Yes	Yes	Sinus infection
Water bottle	1	Never	Yes	Yes	Yes	No
Water bottle	1	Never	No	Yes	Yes	Allergies
Water bottle	1	Never	No	Yes	Yes	Sinus infection
Water bottle	1	Never	Yes	Yes	Yes	Camp crud
Water bottle	1	Never	No	Yes	Yes	No

The firefighters' personal drinking systems are unsanitary. Because the systems are rarely cleaned, they develop a microbial film. This film is not necessarily hazardous, but is likely to give the water a bad taste. The molds growing in the film could be causing allergic responses in some firefighters. An inexpensive water purification technology should be tested for sanitizing drinking systems.

Bacteria and fungi in personal drinking systems. P. Ramsey, J. Domitrovich, A. Williams, and J. Gannon, University of Montana. Supported by MTDC.

Purification of Personal Drinking Systems

This study analyzed water purification technology (chlorine dioxide water purifier tablets) for firefighters' personal drinking systems. A bladder with a drinking tube was tested for microorganisms using different culture media before and 4 hours after a tablet of chlorine dioxide was added to the water.

Chlorine dioxide reduced microbes below detectable concentrations in the water inside the bladder and on the inside of the bladder. Firefighters usually fill their drinking systems at night after they return from the fireline. The tablets could clean their personal drinking system overnight. The systems would not need to be flushed afterward, because the tablets create potable water. Future studies could determine how frequently the cleaning tablets need to be used.

University of Montana researchers P. Ramsey and J. Gannon worked with Aquamira Technologies, Inc. (917 West 600 North, Logan, UT 84321) when studying water purification technologies. Aquamira's product uses chlorine dioxide to sanitize drinking systems. (CamelBak Products, LLC, also sells cleaning tablets that generate chlorine dioxide. CamelBak recommends soaking the system for 5 minutes after the tablets have been added, then rinsing the system and drying it).

Purification of hydration systems: a case study. P. Ramsey, J. Domitrovich, A. Williams, and J. Gannon, University of Montana. Supported by MTDC.