
Toolkit for Public Health and Emergency Management Officials
ISBN: 978-1-100-17344-3
Cat. No.: H128-1/10-623E
HC Pub.: 100596
Health Canada gratefully acknowledges the contributions of the following people in reviewing chapters:
Chris Brown (City of Windsor), Quentin Chiotti (Pollution Probe), Lorraine Davidson (Canadian Centre for Occupational Health and Safety), Nancy Dubois (University of Toronto), Stephan Hamel (New Brunswick Public Health), Sandi Hirst (University of Calgary), Toni Morris-Oswald (Manitoba Health and Healthy Living), Fred Ruf (Outsourcing Services Inc.), Scott Sheridan (Kent State University), Trevor Smith Diggins (Risk Communications Specialist), Sue Sullivan (Canadian Public Health Association), Rae-Anne van de Lande (City of Hamilton).
To receive more information about climate change and health activities at Health Canada, please contact:

Extreme heat is a current health risk. As our climate continues to change, extreme heat events/heat waves are expected to increase in frequency, length and severity, resulting in increased health risks for many Canadians. Older adults, those who are chronically ill and socially disadvantaged people, among others, are more vulnerable to health effects related to extreme heat. These effects can include serious illness and even death. In some parts of Canada, the annual number of extremely hot days is expected to more than double over the next 30 years.
Public health and emergency management officials play a key role in implementing communication strategies to provide practical and useful information to health service providers, caregivers and the public to help manage health risks from extreme heat events. These strategies and their associated messages must be effective, consistent and targeted to the appropriate audiences. Communicating the Health Risks of Extreme Heat Events: Toolkit for Public Health and Emergency Management Officials was developed by Health Canada to help achieve this goal.
The Toolkit is based on best communication practices for addressing health risks from extreme heat events. The practices are drawn from experiences in Canadian communities and internationally. They were developed with input from public health officials and health communication experts, as well as a review of the existing literature.
This Toolkit is intended for use by public health and emergency management officials who are developing or updating heat-health communication strategies. It is designed to guide the development of targeted heat-health communication campaigns and necessary outreach products for specific audiences. Currently, many Canadians do not follow the prevention advice provided by public health fact sheets and the media when extreme heat events occur.1,2 Systematic application of best communication practices in the design and evaluation of heat-health communication campaigns is required to communicate heat-health messages consistently and effectively.
To this end the Toolkit provides:
Individual Canadians have an important responsibility to prepare for extreme heat events and modify their behaviour when weather poses a health risk. Information about the dangers of extreme heat and adaptation options delivered in a timely manner will support the widespread adoption of protective actions by people in communities across Canada.
There is no standard definition of an extreme heat event, commonly known as a "heat wave."
Footnote a Most jurisdictions define extreme heat events based on the potential for hot weather conditions to result in an unacceptable level of health effects, including increased mortality. Environment Canada (Ontario Region) defines a heat wave as "a period with more than three consecutive days of maximum temperatures at or above 32°C [90°F]."
3 However, temperature is only one component of heat, which also depends on humidity, wind speed and radiant load. The weather conditions that could result in health risks depend on the sensitivity, acclimatization and adaptability of the population to extreme heat - that is, heat vulnerability.
In Canada, extreme heat events are not well documented and attributed deaths are often estimated using sources such as media reports. According to the Canadian Disaster Database, five extreme heat events were reported in Canada between 1900 and 2005 (1912, 1936, 1953, 1963, 1988) causing just over 1,200 deaths.4 Other research indicates that in Toronto alone, an average of 120 deaths from extreme heat occurred annually between 1954 and 2000.5 Most recently, in 2005 Toronto experienced 41 extremely hot days (exceeding 30°C/86°F).6 Internationally, there have been a number of devastating extreme heat events, such as:
Chicago (1995) - resulting in over 700 deaths.7,8
Europe (2003) - resulting in over 70,000 deaths.9
In 2007, the Intergovernmental Panel on Climate Change (IPCC) concluded that "hot extremes"
and "heat waves"
are very likely (>90% probability of occurrence) to increase as our climate continues to change.10 This predicted temperature increase is particularly pronounced for night temperatures, resulting in reduced night-time relief from the heat.11 In addition, Environment Canada (Figure 1) forecasts that many cities in Canada can expect a substantial increase in the number of days with temperatures exceeding 30°C/86°F, levels that are dangerous to human health.12,13 These changing weather conditions are a growing concern for individuals and communities in Canada.
Figure 1: Current and projected number of days exceeding 30°C/86°F for Canadian cities
The number of hot days for each city is based on the observed temperature data between 1961 and 1990, and projected for 2021-2040, 2041-2060 and 2081-2100.
Source: Developed by Kharin Slava, Canadian Centre for Climate Modeling and Analysis, Canadian Global Climate Change Model version 3.1, personal communication, 2009. The temperature projections were analyzed with the Special Report on Emissions Scenarios (SRES) using the IPCC middle-of-the-road emissions scenario (A1B).120

During extreme heat events, many people succumb to underlying health conditions (e.g. respiratory, cardiovascular),14 while some may experience heat stroke (Table 1) that could result in death. These health outcomes are preventable and are primarily caused by over-exposure to extreme heat and/or over-exertion for a person's age and/or physical condition.15 To prevent negative health impacts from extreme heat events, public health and emergency management officials can assess community and individual factors contributing to vulnerability and develop intervention programs supported by appropriate communication strategies.
| Heat stroke | The most serious type of heat illness is a result of body heat overload. Signs of heat stroke may include a core body temperature of more than 40°C/104°F, complete or partial loss of consciousness and/or reduced mental ability.15 Sweating is not a good indicator, as there are two types of heat stroke:
|
|---|---|
| Heat exhaustion | Caused by excessive loss of water and salt. Symptoms may include heavy sweating, weakness, dizziness, nausea, headache, diarrhea and muscle cramps. |
| Heat fainting (parade syncope) | Caused by the loss of body fluids through sweating and by lowered blood pressure due to pooling of blood in the legs. Symptoms include temporary dizziness and fainting resulting from an insufficient flow of blood to the brain while a person is standing. |
| Heat cramps | Caused by a salt imbalance resulting from a failure to replace salt lost through excessive sweating. Symptoms are sharp muscle pains. |
| Heat rash (miliaria rubra) | A result of inflammation of clogged sweat glands and accompanied by tiny red spots on the skin, which may give a prickling sensation. |
| Heat edema | Heat-induced swelling frequently noticeable in the ankles, feet and hands, and most often seen in people who are not regularly exposed to heat. |
Source: Canadian Centre for Occupational Health and Safety, 2005.39
Community factors that can increase the likelihood of heat exposure or affect the risk associated with it may include16,17:
Individual factors that can increase the likelihood of heat exposure or the risk associated with it may include:

Heat sensitivity is increased for those who are not regularly exposed to hot environments.21,22 Extreme heat events early in the summer generally result in higher mortality and morbidity than those later in the season.21 This "acclimatization"
is due to physiological adaptation in both cardiovascular and sweating systems.23 Furthermore, the body's ability to acclimatize may be limited for some, such as those with heart disease,24,25 older adults25 and young children, who are also considered to be heat-vulnerable.25
Analyses of extreme heat events help to identify heat-vulnerable groups for which hot weather Table 2.
Health risks from extreme heat may be compounded for those with more than one risk factor. For example, people with a psychiatric illness, taking an antipsychotic drug that affects heat sensitivity, and who live alone may be at greater risk than those with only one of these three risk factors.
Current and future heat vulnerabilities have been studied in Quebec. Climate modelling and a social vulnerability index consisting of age, poverty, social isolation and education indices were used in prediction models (Box 1). This type of forecasting is limited by uncertainty about future socio-demographic conditions. However, by studying populations at risk, health officials can learn about the unique needs in their communities, identify the most heat-vulnerable individuals, and provide targeted advice and services to those in greatest need.

Source: Vescovi, 2007.17,121
As our climate continues to change, weather conditions that already pose risks to health may increase in the future.
The amount of lead time in forecasts of extreme heat events is now allowing public health officials and the public to prepare for dangerous conditions. Heat-related illnesses can be reduced with measures that help people to maintain a normal body temperature (approximately 37°C/99°F). To reduce the likelihood of morbidity and mortality, public health and emergency management officials, together with individual Canadians, need to take measures that include both short- and long-term strategies.
Short-term strategies provide targeted groups with timely, consistent and accurate information to help people make informed decisions and change their behaviour to minimize health risks, such as drinking more water and going to cooling shelters during extreme heat. Many communities in Canada and around the world have developed heat alert and response systems that encourage people to take actions to protect their health.41 The four typical components of heat alert and response systems include:
Long-term strategies are designed to reduce the exposure of the general public to extreme heat and help them adapt more effectively. Such strategies include:
Green roof in Ottawa
Source: Craig A.L. Riedl
Public health and emergency management officials play an important role in communicating short-term and long-term strategies to help individuals, organizations and communities take the most appropriate adaptive actions and make informed decisions to reduce health risks.
To overcome barriers to behavioural change, communication activities must acknowledge that
"there is no 'general public' ... there are many publics, each with differing views and perceptions of health and environment risks."45
Past experiences with health promotion campaigns to prepare for public health emergencies and natural disasters provide useful guidance for developing effective heat-health communication campaigns. Campaigns are most effective when public health and emergency management officials46:
Know your target audience - Identify who you are trying to reach with your heat-health communication campaign and consider their physical conditions, level of knowledge and needs, demographic characteristics, recent experiences, beliefs and values.
The characteristics of a community and population groups (Table 2) that increase heat vulnerability should be assessed at the beginning of your campaign so you can choose appropriate communication strategies and tools. This process, often called formative evaluation, allows you to identify individuals and groups who should be targeted to receive risk communication materials and interventions, and ensure that the needs of your stakeholders are met. This process also focuses efforts and resources to prepare for extreme heat events and helps to tailor the development of "how-to"
information.
Successful heat-health communication campaigns should be targeted to guide heat-vulnerable individuals at four distinct levels of audience organization47:
Targeting communication campaigns requires that heat-vulnerable individuals be separated into groups according to their characteristics. These characteristics could relate to demographics, specific behaviours, attitudes, perceptions of heat-health risks, personal values, lifestyles and opinions.48 These characteristics are key determinants of how people receive and process information from education and outreach campaigns. Empower interested individuals to play a key role in your campaign by including them in the process. This will encourage active participation and increase the chance that communication activities will have an impact.49
You can reach target groups directly and/or indirectly by involving their social networks (e.g. family members, friends, co-workers, opinion leaders, and gatekeepers to information goods and services) to spread heat-health messages and increase awareness of health risks.47 Involving members of social networks also helps them learn about the need to pay close attention to heat-vulnerable people during extreme heat events.
Your heat-health communication campaigns should also target supporting organizations, to raise awareness about heat-health issues, guide the establishment of heat-health action plans (e.g. emergency plans for extreme heat events), and provide direction on preventative measures to minimize health impacts. This will help to ensure that heat-health messages are adopted and distributed (Box 2) and that the information flows to target audiences.
Relevant organizations include:
When community organizations are engaged, they can often bring additional resources to the table along with knowledge of the target audiences and their needs. They may also be encouraged to take the lead on heat-health issues and act as role models for other organizations in the community.47
At the societal level, effective heat-health campaigns aim for long-term impacts to help communities and people cope with extreme heat events. A longer-term impact can be achieved by modifying social norms and implementing supportive policies and regulations to protect those most vulnerable and bring about needed environmental changes, such as reducing the urban heat island effect.
Source: Canadian Red Cross
The Canadian Red Cross developed its Expect the Unexpected program in 1997, following the major floods in Saguenay, Quebec, in 1996. Intended for educators and parents, the program is designed to help youth and their families deal with the impact of natural disasters and adopt disaster preparedness behaviours. The Canadian Red Cross is grateful to the American Red Cross for permitting the adaptation of its Masters of Disasters™ program in order to create the Expect the Unexpected program.
The only disaster-based educational program of its kind in Canada, Expect the Unexpected is designed to help children, youth, educators and parents learn about the importance of disaster preparedness. It features in-class and at-home activities on topics such as climate change, weather events, knowing the risks in your community, safety rules, making a plan, getting a kit and dealing with emotions related to emergencies.41,50
After identifying your target audiences for a campaign, the next step is to develop realistic objectives that fit budgets and that focus on health-related outcomes of both ultimate goals and intermediate objectives.
The ultimate goal of your communication campaign is to reduce heat-related morbidity and mortality. To achieve this, intermediate objectives need to be set to1,47:
Choose the right messenger - In advance of an extreme heat event, you should identify and train credible and empathetic messengers who can move the message forward (e.g. health care providers and caregivers).51
There is no single approach to developing an effective communication campaign. The most appropriate strategy will depend on:
Successful heat-health communication campaigns often include three means of communication to reach the target audience, all of which should be community-based:
Source: The Weather Network
Mass/broadcast media include television, radio, Internet, newspapers and magazines that reach very large audiences.47 To reach specific audiences, campaign planners tailor messages and deliver them through selected vehicles and messengers at times when these audiences are likely to be accessing or using certain sections of particular media.
Recent surveys of Canadians show that most people receive their extreme weather information from mass/broadcast media, through television (56%), radio (35%) and the Internet (27%).52 Partnering and engaging local media is important to establish credibility and ensure dissemination of consistent messages. Messages from mass/broadcast media can often blend into other channels of communication by stimulating discussion, especially if the campaign messages are presented as "news"
rather than "advertising."
The communication framework developed by the Direction de santé publique de l'Agence de la santé et des services sociaux de Montréal is a good example of how interpersonal networks (activities to support health professionals), targeted media (promotional tools) and mass/broadcast media (press relations) are used to communicate heat-health messages to the target audience.
The three communication strategies used include:

Source: Direction de santé publique de l'Agence de la santé et des services sociaux de Montréal, 2009.122
Communication strategies should also be supplemented with targeted media such as fact sheets, pamphlets, posters, fridge magnets, and personal alerts through short message service (SMS), facsimile and e-mail. Some of these could be mailed directly to people's homes or inserted into the newspapers your audience is likely to read. This method gives people an information resource they can use as they become more interested in the campaign.44
Interpersonal networks are crucial and often most powerful. They allow for greater participation in the issue, especially when feedback is required. Interpersonal networks spread public messages by community leaders, health care providers, educators, friends and relatives who will often endorse the messages and enhance their impact.47
Distributing heat-health messages during community and group events is also important. The attention of the targeted audience is already captured, as community events are often well promoted and reported on by the media. For example, messages could be integrated into activities planned by faith-based groups, scientific conferences, and industry, community and outdoor events (e.g. festivals).
Multiple, diverse channels and vehicles should be coordinated to distribute heat-health messages and to reinforce them. For example, mailed fact sheets or fridge magnets should be supplemented with an awareness campaign before the mail-out to increase the likelihood of an audience keeping this material. Shortly after, it is beneficial to follow up with additional heat-health messages using multiple means to spike interest and entice the audience to read the mailed material.44Apply the rule: three messages, three times, using three different ways.48
If the community borders another jurisdiction, the target audience may also receive their health information during extreme heat events from other authorities. It is important to coordinate these heat-health messages and alerts as much as possible to build and maintain credibility, and to make the best use of available resources.
The U.S. Environmental Protection Agency (EPA) has developed fact sheets on risks to health from extreme heat that are tailored to the needs of specific target audiences. The "It's Too Darn Hot"
fact sheet is offered in 17 languages and comes in two versions - the high-literacy version and a simpler version for those with a lower reading ability. EPA also offers a large-font series of fact sheets for people with a visual impairment.53
Source: www.epa.gov/aging/resources/factsheets/index.htm.
Communication products should be tailored to each target audience (Box 4). To enhance understanding and retention of the message, heat-health written material and graphics must be appropriate for the reading level, age range, and ethnic or cultural background of the audience. Focus the message on the abilities of the audience and address their unique challenges and perspectives. The information provided should emphasize practical steps to protect health within available community resources.
Socio-economic factors may prevent people from changing their behaviours in the face of serious risks to health. These challenges include insufficient financial resources for air conditioning, lack of clean water or adequate shelter, inadequate skills and knowledge, limited physical ability, and certain views and beliefs (local preferences, accepted behavioural patterns). Risk communication efforts have more chance of influencing behaviour when they are complemented by programs that remove barriers to action and provide opportunities for citizens to adopt coping strategies. For example, providing free bus tickets during extreme heat events will encourage people to go places where they can cool down. Interventions to overcome barriers to action should take into account the existing capacity of communities and partners. They should also address the need of target audiences and be based on service utilization, availability and accessibility of services, and stakeholders' perceptions of audience need (Box 5).
Effective communication planning must begin well in advance of an extreme heat event to positively influence behavioural change and to help the audience deal with extremely hot weather. Extreme heat and health communication campaigns generally occur over three phases:
Choose the right moment - Your message will have the greatest impact if it is in the right place at the right time. Choose the means of distribution that are most appropriate for your audiences. Look for ways to tie messages to events that will catch the audiences' attention and spark their interest.
Before the Heat Season
To reach targeted individuals in time, awareness campaigns should begin in the spring before extremely hot weather begins and continue during the summer months. Educate audiences about available resources in communities, such as cooling facilities, utility rebates, subsidies and transportation assistance.
Before summer, raising public and stakeholder awareness is more challenging than communication during the heat season. This is because both the media and the public are less likely to get interested and involved in heat-health issues. Communication activities should focus on raising the audiences' curiosity about heat-health issues. This will encourage information sharing and a desire to look for more details from multiple sources. Make sure these sources are available in advance (e.g. websites, fact sheets). This will empower audiences and give people an opportunity to plan their own protective measures.44
It is beneficial to build on and possibly incorporate (where appropriate) heat-health awareness activities into existing community and group events and health promotion campaigns (e.g. West Nile virus) held in the spring. Properly timed and audience-appropriate messages will ensure the best use of resources, contribute to wider audience reach and increase the likelihood of messages being understood and retained.
Many steps to encourage adaptation to extreme heat address more than one barrier to action.
Socio-economic challenges

Newcomers to Canada and cultural barriers
Inadequate skills and knowledge
Limited mobility
Source: Examples are based on actions being taken by the cities of Toronto, Hamilton and Montréal.63,123
During the Heat Season and During an Extreme Heat Event
Heat stroke has a fast onset and low survival rate.32
The timing of communication activities is critical. Early summer extreme heat events result in higher mortality and morbidity than do those occurring later in the season.21 Extra communication efforts are needed early in the season to warn and help protect heat-vulnerable individuals.
During an extreme heat event, providing effective and rapid communication materials emphasizing only three to seven bits of familiar information that audiences can/should remember is very important. This will increase the likelihood of retention of key messages. By repeating these messages often, through different channels and vehicles, you will increase the reach and number of times they hear your message, demonstrate credibility, and provide needed support to those most at risk.54
Heat-related mortality also continues to occur shortly after extreme heat events,55 so it is a good idea to build the recovery phase into your communication campaign. Provide ongoing reminders to the public even after such events have passed (e.g. "we are still recovering from an extreme heat event, continue to drink cool water before you feel thirsty"
).
Be prepared - use the "window of opportunity"
after the extreme heat event to communicate with your audience. This will increase the likelihood of messages being heard and picked up by the audience, and encourage behavioural change.44
Although residents of rural and small town communities are less likely to be affected by the urban heat island effect (i.e. there is more night-time relief from the heat) or crime if they keep their windows open, they are likely to be at high risk for several reasons:

Small towns and rural communities often face unique challenges in developing and implementing extreme heat and health communication campaigns.
These can include:
These communities also have important strengths that can be drawn upon when developing communication plans. These may include:
Authorities in rural communities may need to find innovative approaches to use their strengths and address challenges. For example, because of fewer ways to communicate with the public, heat awareness campaigns may need to focus on empowering people to take independent action by monitoring important weather information and the health of those around them. To facilitate communication with audiences in summer, officials may inform the public about the severity of extreme heat events by displaying a "heat meter"
sign by the side of the road, an entrance to a park or recreational facility. The sign could display community-specific heat warnings such as an advisory, warning or alert. The heat monitor design used by the City of Hamilton is one example that could be adapted to develop a local heat meter sign in rural areas (Box 6).
To distribute heat-health information in rural areas, you could use:
When communicating with intended audiences, take advantage of techniques designed to capture attention, along with strategies that will influence behavioural outcomes.65 It is important to ensure that heat-health messages are accessible, credible, personally relevant, take into consideration existing knowledge and focus on achievable outcomes (Box 7). See Appendix B for the Toronto Health Communication Unit's Message Review Tool to develop messages that address an audience's level of understanding and relevance.
Successful public education campaigns, such as "Quit smoking,"
"Fasten your seat belt"
and "Don't litter,"
have had three strategies in common44:
"the local angle"and the possible impacts that the target audience care about (e.g. health for parents with young children and older adults, performance for those who are physically active) and offer simple solutions (e.g. drink water).
It is important to keep messages consistent throughout all stages of the campaign and between distribution vehicles (e.g. fact sheets, media releases, websites). Consistent messages from all public officials, community leaders, health care providers, educators and other sources help develop and maintain credibility and trust with the audiences. To do this, look for potential inconsistencies with other health-promotion campaigns (e.g. ultraviolet radiation, air quality, infectious diseases, physical activity, green city and energy-use reduction campaigns). It is very important to ensure that heat-health messages are complementary before you distribute them.
"It's good for you"is not a reward that motivates people. Understand the needs of audiences and what will motivate them to consider changing their behaviour (e.g. improved performance for those who are physically active).

Address contradictory messages by integrating heat-health messages into other health-promotion campaigns (Box 8) or developing a databank of health messages for the public when extreme heat events happen at the same time as other public health emergencies or events. This would help to maintain consistency, minimize confusion among the public and give appropriate health protection guidance to your audiences.

Solution:
Incorporate messages about the need to take protective measures against vector-borne diseases into heat-health communication materials (see Appendix D for a fact sheet example).
The following heat-health messages were developed through a review of the scientific literature about risks to health from extreme heat, best practices in health risk communication and the most effective actions to protect Canadians. The messages were reviewed by health communication experts and public health officials in communities developing heat alert and response systems. Explanations for each message and considerations to help minimize contradictory and confusing statements are provided.
The messages are not presented in order of importance. Some may be more appropriate depending on the target audience, timing and vehicle chosen for communication. Testing of these messages with your audience is important to ensure relevance and applicability. Fact sheets aimed at older adults, those who are physically active and parents with young children, which use many of these messages, are included in Appendix D.

Heat illnesses are preventable.
This message empowers the reader. It reduces barriers to action.
While extreme heat can put everyone at risk from heat illnesses, health risks are greatest for:

Heat-vulnerable individuals - The list should accurately represent populations at higher risk in your community (determined through an assessment of individual- and community-level vulnerabilities).
Older adults - Older adults may be faced with compounding factors that could put them at increased risk during extreme heat events. These factors may include chronic illnesses,68,69 impaired thermoregulatory system,70 medications that interfere with the body's cooling mechanisms,36,71-73 social isolation,32 lower literacy26 and poverty.26 The term "older adults"
is seen as appropriate for this target group because it eliminates association with a specific age (e.g. "senior"
usually denotes a person 65 years of age or older). The term "elderly"
may be inappropriate or confusing when addressing communities that include Aboriginal people. "Elder"
is a title given to some Aboriginal people in recognition of their wisdom and is often reserved as a title of honour.74
Infants and young children - Given the unique physiological characteristics of children's bodies and their high dependency on caregivers, they are likely to be at risk during extreme heat events.75,76
People with chronic illnesses - Individuals with breathing difficulties,77 heart problems78 and psychiatric illnesses79-81 are at a higher risk of heat-related health effects.
People who work in the heat - Some work environments expose people to higher heat-health risks. Examples include foundries, steel mills, smelters and glass factories. As well, people who work outdoors (e.g. construction, road repair, open-pit mining and farming), in laundries, restaurant kitchens, bakeries and canneries39 are at higher risk.82
People who exercise in the heat - Physically active individuals who exercise in the heat (e.g. professional athletes, marathon runners, recreational athletes, people who walk or bike outdoors) could face greater environmental heat exposure and physical strain. In addition, some of these people may expect their usual performance despite the dangerous weather conditions.
Homeless people and low-income earners - These populations have limited financial resources to take protective actions and often experience greater social isolation. They therefore experience greater environmental exposures to heat and may also be faced with less access to clean water, cool places, and health and social services.
If you are taking medication or have a health condition, ask your doctor or pharmacist if it increases your health risk in the heat and follow their recommendations.

Some drugs interfere with the body's ability to maintain normal body temperature. Sensitivity can vary widely, so people should be encouraged to seek advice from their doctors and pharmacists.
Heat illnesses include heat stroke, heat exhaustion, heat fainting, heat edema (swelling of hands, feet and ankles), heat rash and heat cramps (muscle cramps).
Watch for symptoms of heat illness, which include:
If you experience any of these symptoms during extreme heat, immediately move to a cool place and drink liquids. Water is best.

Urgency of the situation - Immediate actions need to be taken when signs of heat illness are seen. If not treated immediately, they may result in a life-threatening condition such as heat stroke.13 This urgency should be highlighted in the message.
First aid advice - When symptoms of heat exhaustion are seen, the most effective treatment is to move the person to a cool place.82-84 The message should focus on a cool place rather than an air-conditioned place (e.g. shopping mall, public building). This will °C/9°F cooler than the surrounding area.18
Heat stroke is a medical emergency! Call 911 or your local emergency number immediately if you are caring for someone, such as a neighbour, who has a high body temperature and is either unconscious, confused or has stopped sweating.
While waiting for help - cool the person right away by:

Medical emergency - Heat stroke is a medical emergency and requires immediate medical attention, as the mortality rate can be high.32 Emphasize the immediate need to call 911 or a local emergency number, which should be included in the message.
Sweating - Sweating is not a good indicator of heat stroke for the general public because there are two types of heat stroke - classic (accompanied by little or no sweating, usually occurring in children, those who are chronically ill and older adults) and exertional (accompanied by an increase in body temperature because of strenuous exercise or occupational exposure along with environmental heat, and where sweating is usually present).39
High body temperature - Core body temperature over 40°C/104°F is indicative of heat stroke. However, to get an accurate reading you need to use a rectal thermometer, which may not be available or convenient. Therefore, "high body temperature"
was chosen to describe this sign of heat stroke since immediate action is required.
Cooling advice - Full body submersion in cool water is the fastest method to treat exercise-induced heat stroke (effective among young people, military personnel and athletes with exertional-related heat stroke). However, it is mainly applicable in a clinical setting.85-87 In other settings, cool the person by applying cold water to large areas of the skin or clothing and fan them as much as possible, keeping in mind that cooling larger areas will improve efficiency.88-90
Frequently visit neighbours, friends and older family members, especially those who are chronically ill, to make sure that they are cool and hydrated.

Importance of visiting - Visitors can help identify signs of heat illness that could be missed over the telephone. Checking with a telephone call is sufficient only for people who have excellent self-care ability.
Frequency of visits - It is essential to use careful judgment of a person's ability for self-care and past experiences in hot environments when determining how often to visit the person under your care.
Drink plenty of cool liquids, especially water, before you feel thirsty to decrease your risk of dehydration. Thirst is not a good indicator of dehydration.

Drink "before you feel thirsty"
- Many people, especially older adults, may be in a state of chronic dehydration because of a reduced ability to feel thirst, the body's reduced ability to react to dehydration and concern over frequent urination.26,27 By the time a person feels thirst, they have already lost about 2% of their body water and dehydration has occurred.91 One method of reminding people to drink water is by advising them to leave a colourful glass by the sink and to drink from it after every hand washing.92
Volume of water - Individuals should take personal responsibility for keeping hydrated.93 People gain water from food and liquid intake, and lose water through urination, sweating and normal metabolic processes. Everyone has different water needs, depending on their activity level, diet, exposure to heat, perspiration rate and sodium concentration in sweat.94 Canada's Food Guide recommends drinking "more water in hot weather or when you are very active."
95
Water versus juice or sports drinks - Water is the best hydrating liquid. Sports drinks and juices are popular but are also expensive. Considering the large quantities of juice or sports drinks that need to be consumed to stay properly hydrated in the heat, consumption of these liquids could be dangerous for diabetics. On the other hand, as our society has developed a taste for juices and sodas, flavouring water with natural fruit juice may make it more appealing.83
Caffeinated beverages - Caffeine is a diuretic that increases urination. Regular caffeine users are adjusted to the effect of caffeine, minimizing its diuretic properties.98 Therefore, people may continue to drink caffeinated beverages during extreme heat, but should not increase consumption during this time.
Cool liquids - Research suggests that people will not drink enough water unless it has been cooled (21-24°C/70-65°F).25
Fruits and vegetables - Fruits and vegetables have high water content and are a great snack to increase daily water consumption.
Reschedule or plan outdoor activities during cooler parts of the day.

Defining "cooler parts of the day"
- Every region has its own micro-climate. Depending on the location of a person's residence, their body could get a heat load from direct sunlight during the day or from pavement and buildings even after the sun sets.99 It is important to let people decide which time is cooler and more comfortable for outdoor activities.
Give options - For those who may want to participate in outdoor activities, offer safer options such as:
West Nile virus - Mosquitoes can transmit West Nile virus and are most active during cooler parts of the day. To minimize the possibility of infection, include the following West Nile virus safety tip from Health Canada101:
Encourage the audience to move around - Moving around may actually reduce the possibility of fainting in the heat. People who sit or stand for an extended period of time may be at greater risk during extreme heat events.83
Acclimatization - Exposure to outdoor temperatures in the summer helps to prepare a healthy person's body for the heat through acclimatization and may reduce the probability of heat illnesses. Acclimatization takes time and will depend on individual characteristics. Guidelines for healthy people who exercise or work in the heat indicate that it requires 10 to 14 days of exposure to hot temperatures for the body to adapt.102 Consequently, even for healthy people strenuous activities in the heat could be dangerous, especially early in the heat season.
Wear loose-fitting, light-coloured clothing made of breathable fabric.

Clothing - Clothing thickness and the amount of skin covered will affect the efficiency of heat transfer and the evaporation of sweat from the skin.103 Insulation, permeability and breathability are characteristics important to consider when determining the most appropriate clothes to wear during extreme heat.104
Never leave people or pets in your care inside a parked vehicle or in direct sunlight.

"People or pets in your care"
versus "anyone"
- It is not feasible to list all people (e.g. infants, those who are chronically ill) who should not be left in the vehicle during extreme heat. The designation "people or pets in your care"
implies those with caregiver needs. Indicating "anyone"
may appear to be too generic and could result in mistrust and disregard of the message.
Temperature inside a vehicle could get very dangerous - When the outside air temperature is 23°C/73°F, the temperatures inside a vehicle can be extremely dangerous - more than 50°C/122°F.105
Take a break from the heat by spending a few hours in a cool place. It could be a tree-shaded area, swimming facility or an air-conditioned spot such as a public building, shopping mall, grocery store, place of worship or public

Time needed for sufficient cooling - This depends on individual characteristics. Every person needs to judge their own comfort level and when they feel refreshed after cooling.
Unique community cooling options - Develop this message based on the existing air-conditioned resources and programs that are most appropriate for your target audience and their demographics (e.g. cooling centre, public library, cooling room in an apartment building, place of worship, shopping mall, grocery store). Keep in mind that some people may not have access to air-conditioned places. Therefore, it is a good idea to highlight other cooling options (e.g. waterfront locations, tree-shaded areas, swimming facility or spray pads - some of these may be excellent choices for children).
Air-conditioned spot - Use of air conditioners during extreme heat events diminishes heat-health risks.32 However, air conditioners can use a lot of energy, give off greenhouse gases and may decrease acclimatization to heat. Therefore, public health information should highlight alternatives and educate about the most efficient use of air conditioners. Messages that suggest using air conditioners should include user guidelines such as:
Take cool showers or baths until you feel refreshed.

"Cool"
versus "cold"
- Some people who are at a higher risk from extreme heat may have other health conditions such as cardiovascular disorders. Exposure to a rapid shift in temperature could have health consequences.107 Recommending a "cool"
rather than "cold"
shower or bath minimizes this risk.
Bathroom safety - Older adults108 and children109 may be at increased risk of injuries while in the bath tub. Messages to these groups could add additional suggestions to protect them from injuries, such as including Health Canada's fall prevention guidelines:
Misting - Misting with cool water is helpful during extreme heat. Mist cools the body by conductive cooling and contributes to evaporative cooling, especially when windy.
Cooling hands and forearms - Cooling a person's hands and forearms can improve athletic and occupational performance and comfort while reducing heat strain.13,36,73,84,85,112
Prepare meals that don't need to be cooked in your oven.

Ovens produce a lot of heat. Cooking with an oven will increase the indoor temperature, which is difficult to lower during extreme heat events, especially without an air conditioner.
Block sun out by closing awnings, curtains or blinds during the day.

"Greenhouse effect"
- Allowing the sun to beam through the windows will increase your indoor temperature due to the "greenhouse effect"
and will result in trapping hot air in the home. Installing and closing awnings or shutters is very effective at keeping the heat outside, since the sun's rays will be blocked before they reach the window.
Plan for the future - Planting a broadleaf tree on the side of the house where the sun hits during the hottest part of the day will provide shade during the summer months and shelter the house from radiant heat.
Avoid sun exposure. Shade yourself by wearing a wide-brimmed, breathable hat or using an umbrella.

Heat is made up of four main physical and environmental factors that contribute to the body's heat load: humidity, radiant load, temperature and wind speed.39 Direct sun exposure will increase the radiant load and total heat exposure. This is why shaded areas are cooler and wearing a wide-brimmed, breathable hat or using an umbrella in the sun is recommended.
Hats - Basic scientific principles, as well as designs that have evolved in hot climates, indicate that hats worn to protect against the sun's ultraviolet (UV) rays and sunburn should be:
Umbrella - Using an umbrella to avoid sun (radiant load) exposure is ideal as it does not interfere with evaporative cooling and provides a lot of shade.
Sunburn - UV exposure could result in sunburn. Sunburned skin loses its sweating efficiency, which impairs the ability of the body to regulate its temperature.115
Sun safety - If sun exposure is unavoidable, recommend the use of a sunscreen lotion that is SPF 15 or higher and that users follow the manufacturer's directions for safe use.116 Remind your audience that sunscreen and insect repellents can be safely used together, and that they should apply the sunscreen first, then the insect repellent.
Formal evaluation of heat-health communication campaigns can help to improve communication strategies and messages, and will ensure that they are costeffective and appropriate for your audience.
There are three main types of evaluation:

To evaluate programs, campaign leaders may use informal feedback from stakeholders and target audiences, as well as their own observations from past experiences. However, this type of evaluation is often based on incomplete data and may be biased. Formal evaluation is more credible and is better for accurately capturing the strengths and weaknesses of heat-health communication campaigns.117
Formal and informal evaluations should117:
The evaluation plan should be simple and costeffective. It should also include those involved in developing and participating in the campaign (e.g. audiences, stakeholders, government and nongovernment organizations).118 Engaging these groups and receiving constant feedback will ensure identification of common goals among stakeholders, realistic expectations of the campaign outcomes, and appropriate measurable indicators for use in evaluation.119
Develop an evaluation plan along with the communication campaign to best capture opportunities for data gathering during the implementation phase. Base the plan on the ultimate goals and intermediate objectives of the campaign.
Evaluations could be completed using qualitative (focus groups, interviews, questionnaires, diaries) and quantitative (surveys, analysis of records, service utilization, morbidity/mortality data) methods (Appendix F).
Campaign evaluations will help you to117,118:
Process evaluation is used to examine a program during its implementation.
A process evaluation examines services related to implementation of the campaign and allows the campaign leader to assess117,118:
Source: Health Communication Unit, 2007.117
As part of a process evaluation, it is important to monitor and evaluate news and trends to identify emerging needs of the audience and stakeholders, allow for timely response to new scientific developments, address criticisms and build partnerships.119 Monitoring includes:
Outcome evaluation is appropriate for well-developed heat-health communication campaigns that have been implemented over a number of years and have made progress toward campaign objectives.
Outcome evaluation, also known as summative evaluation, should focus on117:
Intermediate objectives
Ultimate goals
Source: Health Communication Unit, 2007.117
Document the results of the formal evaluation to guide future efforts to strengthen heat-health communication activities. Share them with team members and stakeholders, through presentations, discussions, meetings and e-mail updates.119 The evaluation reports should be published and available for dissemination.Footnote c
Evaluation activities are most beneficial when they are ongoing, as behaviour changes take place over time. Long-term efforts to measure impacts are needed to ensure sustained behavioural adaptations during extreme heat events. Even if behavioural changes are observed shortly after a program is launched, it does not mean that they will be sustained over time.119
The plain-language checklist can be used to develop or modify heat-health messages.
Source: Adapted from Health Canada, 1999 and U.S. Centers for Disease Control and Prevention, 2002.54,124
This message review tool can be used with stakeholders and target audiences to evaluate the appropriateness of heat-health messages.
Final Recommendation
Source: Adapted from the Health Communication Unit, 2002.125
Heat illnesses are preventable.
While extreme heat can put everyone at risk from heat illnesses, health risks are greatest for:
If you are taking medication or have a health condition, ask your doctor or pharmacist if it increases your health risk in the heat and follow their recommendations.
Heat illnesses include heat stroke, heat exhaustion, heat fainting, heat edema (swelling of hands, feet and ankles), heat rash and heat cramps (muscle cramps).
Watch for symptoms of heat illness, which include:
If you experience any of these symptoms during extreme heat, immediately move to a cool place and drink liquids. Water is best.
Heat stroke is a medical emergency! Call 911 or your local emergency number immediately if you are caring for someone, such as a neighbour, who has a high body temperature and is either unconscious, confused or has stopped sweating.
While waiting for help - cool the person right away by:
Frequently visit neighbours, friends and older family members, especially those who are chronically ill, to make sure that they are cool and hydrated.
Drink plenty of cool liquids, especially water, before you feel thirsty to decrease your risk of dehydration. Thirst is not a good indicator of dehydration.
Reschedule or plan outdoor activities during cooler parts of the day.
Wear loose-fitting, light-coloured clothing made of breathable fabric.
Never leave people or pets in your care inside a parked vehicle or in direct sunlight.
Take a break from the heat by spending a few hours in a cool place. It could be a tree-shaded area, swimming facility or an air-conditioned spot such as a public building, shopping mall,
Take cool showers or baths until you feel refreshed.
Prepare meals that don't need to be cooked in your oven.
Block sun out by closing awnings, curtains or blinds during the day.
Avoid sun exposure. Shade yourself by wearing a wide-brimmed, breathable hat or using an umbrella.
Protect yourself from the dangers of very HOT weather
It's way too HOT!

Hot temperatures can be dangerous, especially if you have:
If you are taking medication or have a health condition, ask your doctor or pharmacist if it increases your health risk in the heat and follow their recommendations.
Heat illnesses include heat stroke, heat exhaustion, heat fainting, heat edema (swelling of hands, feet and ankles), heat rash and heat cramps (muscle cramps). Heat illnesses can affect you quickly and are mainly caused by over-exposure to heat or over-exertion in the heat.
Tune in regularly to local weather forecasts and alerts so you know when to take extra care.
Arrange for regular visits by family members, neighbours or friends during very hot days in case you need assistance. Visitors can help identify signs of heat illness that could be missed over the phone.
If you have an air conditioner, make sure it works properly before the hot weather starts. Otherwise, find an air-conditioned spot close by where you can cool off for a few hours during very hot days. This will help you cope with the heat better.
Watch for symptoms of heat illness, which include:
If you experience any of these symptoms during hot weather, immediately move to a cool place and drink liquids. Water is best.
While waiting for help - cool the person right away by:
Drink plenty of cool liquids, especially water, before you feel thirsty to decrease your risk of dehydration. Thirst is not a good indicator of dehydration.
Dress for the weather - Wear loose-fitting, light-coloured clothing made from breathable fabric.
Keep your home cool.
If your home is extremely hot:
Never leave people or pets in your care inside a parked vehicle or in direct sunlight.
Reschedule or plan outdoor activities during cooler parts of the day.
Avoid sun exposure. Shade yourself by wearing a wide-brimmed, breathable hat or using an umbrella.
Public Health Agency of Canada's "You CAN prevent falls!"
www.phac-aspc.gc.ca/seniors-aines/publications/public/injury-blessure/preventeviter/ index-eng.php
Health Canada's "It's Your Health - Insect Repellents"
www.hc-sc.gc.ca/hl-vs/iyh-vsv/life-vie/insect-eng.php
Health Canada's "Sun Safety"
www.hc-sc.gc.ca/hl-vs/pubs/sun-sol/safety-prudence-eng.php
Environment Canada's "Air Quality Health Index"
www.airhealth.ca
Protect yourself from the dangers of EXTREME HEAT
You're ACTIVE in the HEAT! You're at RISK!

Being physically active provides many health benefits, but during extreme heat it can put you at risk even if you are healthy. Your risk increases if you have:
If you are taking medication or have a health condition, ask your doctor or pharmacist if it increases your health risk in the heat and follow their recommendation.
Heat illnesses can lead to long-term health problems and even death. These illnesses include heat stroke, heat exhaustion, heat fainting, heat edema (swelling of hands, feet and ankles), heat rash and heat cramps (muscle cramps), and are mainly caused by over-exposure to extreme heat or over-exertion for a person's age and physical condition.
Your body produces heat, especially during physical activity. Hot air and exposure to direct sun rays or hot surfaces also heat your body. This heat is lost by contact with cool air and by sweat production, which cools your body as the sweat evaporates. Weather conditions play a big role in how your body regulates its temperature. For example, if it's windy, sweat evaporates faster, which helps to cool you. However, high humidity slows down this process, contributing to increased body temperature.
Your body is not used to (not acclimatized to) extreme heat at the beginning of the summer. You are also not acclimatized if you don't exercise regularly during hot weather.
Protect your health - watch for symptoms of heat illness, which include:
If you experience any of these symptoms during extreme heat, immediately move to a cool place and drink liquids. Water is best.
Heat stroke is a medical emergency! Call 911 or your local emergency number immediately if you are caring for someone, such as a running partner, who has a high body temperature and is either unconscious or confused.
While waiting for help - cool the person right away by:
Never leave people or pets in your care inside a parked vehicle or in direct sunlight.
Drink plenty of cool liquids, especially water, before you feel thirsty. Thirst is not a good indicator of dehydration. By the time you feel thirsty, you are already dehydrated.
Reschedule or find alternatives - If you can, reschedule strenuous outdoor activity to a cooler part of the day or another day. There are ways in which you can still be physically active while avoiding the heat, such as:
Be realistic - Try not to expect the usual performance from yourself during extreme heat.
Take extra water breaks - Move into the shade, drink water and remove gear, such as a helmet or equipment, to let your body cool off.
Avoid sun exposure - Exposure to direct sun will heat your body and can result in sunburn. Sunburned skin loses its sweating efficiency, which impairs your body's ability to regulate its temperature.
Recover - Allow your body to recover after heat exposure. Spend a few hours in a cooler tree-shaded area or somewhere that's air conditioned, such as your home, a shopping mall, grocery store, public building or public library.
Health Canada's "It's Your Health - Insect Repellents"
www.hc-sc.gc.ca/hl-vs/iyh-vsv/life-vie/insect-eng.php
Health Canada's "Sun Safety"
www.hc-sc.gc.ca/hl-vs/pubs/sun-sol/safety-prudence-eng.php
Public Health Agency of Canada's "Canada's Physical Activity Guide to Healthy Active Living"
www.phac-aspc.gc.ca/hp-ps/hl-mvs/pag-gap/pdf/handbook-eng.pdf
Environment Canada's "Air Quality Health Index"
www.airhealth.ca
Protect your child from the dangers of EXTREME HEAT
Keep children COOL!

Extreme heat can be dangerous for all children, especially for infants and young children.
Heat illnesses include heat stroke, heat exhaustion, heat fainting, heat edema (swelling of the hands, feet and ankles), heat rash (prickly heat) and heat cramps (muscle cramps). They are mainly caused by over-exposure to heat or over-exertion in the heat, and if not prevented, can lead to long-term health problems
Stay informed about local weather forecasts and alerts so you know when to take extra care.
If you have an air conditioner, make sure it works properly before the hot weather starts. Otherwise, find an air-conditioned spot near you that you can use to cool off for a few hours during extreme heat.
Learn about ways to keep your home cool during the summer. For example, if you live in a house, plant trees on the side where the sun hits the house during the hottest part of the day.
Stay alert for symptoms of heat illness. They include:
If you see any of these signs during extreme heat immediately move the child to a cool place and give liquids. Water is best. If you are breastfeeding your child, breast milk will provide adequate hydration, but remember to keep yourself hydrated so you can produce a sufficient amount of milk.
Heat stroke is a medical emergency! Call 911 or your local emergency number immediately if you are caring for a child who has a high body temperature and is unconscious, confused, or has stopped sweating.
While waiting for help - cool the child right away by:
Children most at risk include those with breathing difficulties (asthma), heart conditions, kidney problems, mental and physical disabilities, developmental disorders, diarrhea, and those who take certain medications. Ask your doctor or pharmacist if the medication increases risk to their health in the heat and follow their recommendations.
DEHYDRATION is dangerous. Give plenty of cool liquids to drink, especially water, before your child feels thirsty.
Dress your child in loose-fitting, light-coloured clothing made from a breathable fabric.
Keep your home cool.
If your home is extremely hot:
Never leave children inside a parked vehicle or in direct sunlight.
Reschedule or plan outdoor activities during cooler parts of the day.
Avoid sun exposure - Keep your child in the shade or protected from the sun by wearing a wide-brimmed, breathable hat or shade them with an umbrella.
Health Canada's "Babies, children and sun safety"
www.hc-sc.gc.ca/hl-vs/pubs/sun-sol/babies_child-bebes_enfant-eng.php
Health Canada's "Is your child safe?"
www.hc-sc.gc.ca/cps-spc/pubs/cons/child-enfant/index-eng.php
Health Canada's "It's Your Health - Insect Repellents"
www.hc-sc.gc.ca/hl-vs/iyh-vsv/life-vie/insect-eng.php
Environment Canada's "Air Quality Health Index"
www.airhealth.ca
[Citizens of public] Urged to Take Precautions for Upcoming Extreme Heat Event
[DATE] For Immediate Release
[PLACE] - The Chief Medical Officer of Health, [NAME], is advising [PLACE] to take steps to prevent heat-related illness during the upcoming extreme heat event, also known as a "heat wave."
With temperatures expected to rise in the next [days], Environment Canada has issued a humidex advisory (humidex values in excess of 40).
While extreme heat can put everyone at risk from heat illnesses, health risks are greatest for older adults, infants and young children, people with chronic illnesses such as breathing difficulties, heart conditions or psychiatric illnesses, people who work or who exercise in the heat, homeless people and low-income earners. Those who take medication or have a health condition should ask their doctor or pharmacist if it increases their health risk in the heat and follow their recommendations.
Heat illnesses are preventable, but they can lead to long-term health problems and even death. If any symptoms of heat illness are present (such as dizziness or fainting, nausea or vomiting, headache, rapid breathing and heartbeat, or extreme thirst), immediately move to a cool place and drink liquids. Water is best. The most dangerous heat illness is heat stroke, with symptoms that include complete or partial loss of consciousness or confusion and high body temperature. If caring for someone with these symptoms, call [LOCAL EMERGENCY NUMBER] immediately. While waiting for help, cool the person right away by moving them to a cool place, applying cold water to large areas of the skin or clothing and fanning the person as much as possible.
Public health officials urge everyone to stay alert and take precautions. Remember to frequently visit neighbours, friends and older family members, especially those who are chronically ill, to make sure that they are cool and hydrated.
[PLACE] Public Health recommends taking the following actions to stay cool:
Additional tips on how to stay safe and what to do during an extreme heat-related emergency are available on the following websites: [Insert web links]
MEDIA CONTACT: [NAME, PHONE NUMBER]
Source: Adapted from the Health Communication Unit, 2007.117
Note that this document uses "extreme heat event"
rather than "heat wave."
Focus groups with older adults in rural communities across Canada showed this to be the most effective communication tool (Public Health Agency of Canada, 2007).64
For a good evaluation example of a heat-health communication campaign see "Evaluation of the Education Campaign on Health Risks Associated with Heat Waves and on Related Protection Measures"
developed by the Direction de santé publique de l'Agence de la santé et des services sociaux de Montréal, 2009.122