Recommended
Recommended
More Related Content
More from JA Larson
More from JA Larson (20)
Recently uploaded
Recently uploaded (20)
Aus 151126 presentation fpa16_heat injury
- 2. Sponsor: Directorate of Army Health HEAT INJURY AWARENESS Army Force Preservation Awareness Training 2016
- 3. Defence Policy requires all personnel to receive annual heat injury awareness training. The Army’s capability depends on its members being fully acclimatised and knowing how to prevent and manage a heat injury casualty. Purpose
- 4. Risk Factors Risk Management Heat Illness and Heat Injuries Heat Injury Management Responsibilities Reporting Scope
- 5. Risk Factors
- 7. Environmental factors – air temperature – humidity – air movement – heat radiation – temperature of surrounding objects Risk Factors
- 8. Activity levels Accumulation of activity over several days Clothing (i.e. t-shirts, body armour, MOPP) Failure to acclimatise Lower physical fitness Underlying illness Poor nutrition Risk Factors
- 9. Dehydration Salt depletion Alcohol/Caffeinated drinks/Supplements Medications Higher body mass/fat Personal motivation Risk Factors
- 10. Risk Management
- 11. Physiological adaptation that occurs in response to graduated exposure to the target environment: – 10 to 14 days is required for 95% of the population to have complete acclimatisation – 100 minutes per day in the target environment – Gradually increase the level of physical exertion over the 10-14 day period – Note: air conditioning degrades the rate of acclimatisation and deacclimatisation can occur quickly Acclimatisation
- 12. Results: – sweat at lower temperature – increased volume of sweat – decrease in amount of salt secreted in sweat – increased heat dissipation = lower core body temperature Acclimatisation = Less risk for heat injury Acclimatisation
- 13. Heat Stress Monitors • Quest 34 (QT 34) - Used by trained health professionals only
- 14. Heat Stress Monitors •Environmental Stress Index Monitor (ESIM) 2.0 - Used by any member of the ADF, AAC or APS, Defence Civilian or contractor
- 15. Army Work Tables
- 16. Heat Risk Injury Level MINIMUM MANAGEMENT REGIME Low The Low risk level requires monitoring of heat stress symptoms. Treatment and evacuation plans should be in place. Moderate The Moderate risk level requires active management oversight. Heat stress symptoms shall be monitored and both treatment and evacuation resources shall be available. High The High risk level requires careful management. Constant vigilance of heat stress symptoms shall be maintained. A Medical Technician (MT) with access to both a Medical Officer (MO) via telemedicine-link and effective emergency cooling must be available within 15 minutes. Emergency evacuation resources shall be available. Heat casualty rates up to five per cent should be anticipated. Extreme The Extreme risk level requires critical management. All personnel shall be fully acclimatised, fit, hydrated, rested and not suffering any illnesses. Activities shall only be undertaken with the express authority of a formation level commander or higher. Activity programmes shall be adjusted to minimise exposure to this level of risk. This level requires intense vigilance for heat stress symptoms and positive monitoring of food and water intake. A MT with access to both a MO via telemedicine-link and effective emergency cooling must be available within five minutes. A MO and effective emergency cooling shall be available within one hour. Heat casualty rates greater than 5 per cent can be anticipated.
- 17. Activities and rate of effort ACTIVITIES AND RATE OF EFFORT DESCRIPTION Light Work Moderate Work Heavy Work Very Heavy Work Walking: •Hard surface, no load at ≤ 4.5 kph •Hard surface, 20 kg load at < 4 kph •Hard surface, 30 kg load at < 3.5 kph •Sand, no load at < 3.5 kph Walking: •Hard surface, no load at 4.5–6.0 kph •Hard surface, 20 kg load at 4.0–5.5 kph •Hard surface, 30 kg load at 3.5–5.0 kph •Sand, no load at 3.5–4.5 kph Walking: •Hard surface, no load at > 6.0 kph •Hard surface, 20 kg load at > 5.5 kph •Hard surface, 30 kg load at > 5.0 kph •Sand, no load at > 4.5 kph Running: •Running at speed > 12 km/hr (12 min BFA) •Sprint running during physical training •MOUT training— urban rushing Lift and carry 155 mm shells at < 2 per minute Lift and carry 155 mm shells at 3–4 per minute Lift and carry 155 mm shells at > 4 per minute Fire and movement (Infantry Minor Tactics) Drill and ceremonial Patrolling Digging with entrenching tool Driving, tracked vehicle Weapon maintenance Small arms weapons firing Digging with a pick and shovel Obstacle Course crossing
- 18. Army Work Table WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour* MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <25 <22 <19 NL ¾ NL ¾ 50/10 ¾ 30/30 ¾ 25–26 22–23 19–20 NL ¾ NL ¾ 40/20 ¾ 20/40 ¾ 27–28 24–25 21–22 NL ¾ 50/10 1 30/30 1 20/40 1 29–30 26–27 23–24 NL ¾ 40/20 1 30/30 1 10/50 1 31 28 25 NL ¾ 30/30 1 20/40 1 5/55 1 32 29 26 50/10 1 20/40 1 10/50 1 5/55 1 33 30 27 40/20 1 10/50 1 10/50 1 CM 1 34 31 28 30/30 1 10/50 1 CM 1¼ CM 1 35 32 29 20/40 1 CM 1 CM 1¼ CM 1 36 33 30 10/50 1 CM 1 CM 1¼ CM 1 ≥37 ≥34 ≥31 CM 1 CM 1 CM 1¼ CM 1
- 19. Army Work Table WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour* MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <25 <22 <19 NL ¾ NL ¾ 50/10 ¾ 30/30 ¾ 25–26 22–23 19–20 NL ¾ NL ¾ 40/20 ¾ 20/40 ¾ 27–28 24–25 21–22 NL ¾ 50/10 1 30/30 1 20/40 1 29–30 26–27 23–24 NL ¾ 40/20 1 30/30 1 10/50 1 31 28 25 NL ¾ 30/30 1 20/40 1 5/55 1 32 29 26 50/10 1 20/40 1 10/50 1 5/55 1 33 30 27 40/20 1 10/50 1 10/50 1 CM 1 34 31 28 30/30 1 10/50 1 CM 1¼ CM 1 35 32 29 20/40 1 CM 1 CM 1¼ CM 1 36 33 30 10/50 1 CM 1 CM 1¼ CM 1 ≥37 ≥34 ≥31 CM 1 CM 1 CM 1¼ CM 1
- 20. Army Work Table WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour* MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <25 <22 <19 NL ¾ NL ¾ 50/10 ¾ 30/30 ¾ 25–26 22–23 19–20 NL ¾ NL ¾ 40/20 ¾ 20/40 ¾ 27–28 24–25 21–22 NL ¾ 50/10 1 30/30 1 20/40 1 29–30 26–27 23–24 NL ¾ 40/20 1 30/30 1 10/50 1 31 28 25 NL ¾ 30/30 1 20/40 1 5/55 1 32 29 26 50/10 1 20/40 1 10/50 1 5/55 1 33 30 27 40/20 1 10/50 1 10/50 1 CM 1 34 31 28 30/30 1 10/50 1 CM 1¼ CM 1 35 32 29 20/40 1 CM 1 CM 1¼ CM 1 36 33 30 10/50 1 CM 1 CM 1¼ CM 1 ≥37 ≥34 ≥31 CM 1 CM 1 CM 1¼ CM 1
- 21. Army Work Table WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour* MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <25 <22 <19 NL ¾ NL ¾ 50/10 ¾ 30/30 ¾ 25–26 22–23 19–20 NL ¾ NL ¾ 40/20 ¾ 20/40 ¾ 27–28 24–25 21–22 NL ¾ 50/10 1 30/30 1 20/40 1 29–30 26–27 23–24 NL ¾ 40/20 1 30/30 1 10/50 1 31 28 25 NL ¾ 30/30 1 20/40 1 5/55 1 32 29 26 50/10 1 20/40 1 10/50 1 5/55 1 33 30 27 40/20 1 10/50 1 10/50 1 CM 1 34 31 28 30/30 1 10/50 1 CM 1¼ CM 1 35 32 29 20/40 1 CM 1 CM 1¼ CM 1 36 33 30 10/50 1 CM 1 CM 1¼ CM 1 ≥37 ≥34 ≥31 CM 1 CM 1 CM 1¼ CM 1
- 22. Army Work Table WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour* MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <25 <22 <19 NL ¾ NL ¾ 50/10 ¾ 30/30 ¾ 25–26 22–23 19–20 NL ¾ NL ¾ 40/20 ¾ 20/40 ¾ 27–28 24–25 21–22 NL ¾ 50/10 1 30/30 1 20/40 1 29–30 26–27 23–24 NL ¾ 40/20 1 30/30 1 10/50 1 31 28 25 NL ¾ 30/30 1 20/40 1 5/55 1 32 29 26 50/10 1 20/40 1 10/50 1 5/55 1 33 30 27 40/20 1 10/50 1 10/50 1 CM 1 34 31 28 30/30 1 10/50 1 CM 1¼ CM 1 35 32 29 20/40 1 CM 1 CM 1¼ CM 1 36 33 30 10/50 1 CM 1 CM 1¼ CM 1 ≥37 ≥34 ≥31 CM 1 CM 1 CM 1¼ CM 1
- 23. Army Work Table WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour* MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <25 <22 <19 NL ¾ NL ¾ 50/10 ¾ 30/30 ¾ 25–26 22–23 19–20 NL ¾ NL ¾ 40/20 ¾ 20/40 ¾ 27–28 24–25 21–22 NL ¾ 50/10 1 30/30 1 20/40 1 29–30 26–27 23–24 NL ¾ 40/20 1 30/30 1 10/50 1 31 28 25 NL ¾ 30/30 1 20/40 1 5/55 1 32 29 26 50/10 1 20/40 1 10/50 1 5/55 1 33 30 27 40/20 1 10/50 1 10/50 1 CM 1 34 31 28 30/30 1 10/50 1 CM 1¼ CM 1 35 32 29 20/40 1 CM 1 CM 1¼ CM 1 36 33 30 10/50 1 CM 1 CM 1¼ CM 1 ≥37 ≥34 ≥31 CM 1 CM 1 CM 1¼ CM 1
- 24. Continuous Army Work Table Must be used with Recovery Table WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <19 NL ½ NL ½ NL ½ 55 ½ 55 ½ 19–20 NL ½ NL ½ 180 ½ 50 ½ 50 ½ 21–22 NL ½ NL ½ 100 ½ 45 ½ 45 ½ 23–24 <22 <19 NL ½ NL ¾ 75 ¾ 40 ¾ 25–26 22–23 19–20 NL ½ NL ¾ 70 ¾ 35 ¾ 27–28 24–25 21–22 NL ½ 150 ¾ 65 1 30 1 29–30 26–27 23–24 NL ¾ 100 ¾ 55 1 25 1 31 28 25 NL ¾ 80 ¾ 50 1 20 1 32 29 26 180 ¾ 70 ¾ 45 1 20 1 33 30 27 140 ¾ 55 ¾ 35 1 15 1 34 31 28 120 ¾ 50 1 35 1 10 1 35 32 29 100 ¾ 45 1 30 1 10 1 36 33 30 80 1 45 1 30 1 10 1 ≥37 ≥34 ≥31 70 1 40 1 25 1 5 1
- 25. Continuous Army Work Table Must be used with Recovery Table WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <19 NL ½ NL ½ NL ½ 55 ½ 55 ½ 19–20 NL ½ NL ½ 180 ½ 50 ½ 50 ½ 21–22 NL ½ NL ½ 100 ½ 45 ½ 45 ½ 23–24 <22 <19 NL ½ NL ¾ 75 ¾ 40 ¾ 25–26 22–23 19–20 NL ½ NL ¾ 70 ¾ 35 ¾ 27–28 24–25 21–22 NL ½ 150 ¾ 65 1 30 1 29–30 26–27 23–24 NL ¾ 100 ¾ 55 1 25 1 31 28 25 NL ¾ 80 ¾ 50 1 20 1 32 29 26 180 ¾ 70 ¾ 45 1 20 1 33 30 27 140 ¾ 55 ¾ 35 1 15 1 34 31 28 120 ¾ 50 1 35 1 10 1 35 32 29 100 ¾ 45 1 30 1 10 1 36 33 30 80 1 45 1 30 1 10 1 ≥37 ≥34 ≥31 70 1 40 1 25 1 5 1
- 26. WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <19 NL ½ NL ½ NL ½ 55 ½ 55 ½ 19–20 NL ½ NL ½ 180 ½ 50 ½ 50 ½ 21–22 NL ½ NL ½ 100 ½ 45 ½ 45 ½ 23–24 <22 <19 NL ½ NL ¾ 75 ¾ 40 ¾ 25–26 22–23 19–20 NL ½ NL ¾ 70 ¾ 35 ¾ 27–28 24–25 21–22 NL ½ 150 ¾ 65 1 30 1 29–30 26–27 23–24 NL ¾ 100 ¾ 55 1 25 1 31 28 25 NL ¾ 80 ¾ 50 1 20 1 32 29 26 180 ¾ 70 ¾ 45 1 20 1 33 30 27 140 ¾ 55 ¾ 35 1 15 1 34 31 28 120 ¾ 50 1 35 1 10 1 35 32 29 100 ¾ 45 1 30 1 10 1 36 33 30 80 1 45 1 30 1 10 1 ≥37 ≥34 ≥31 70 1 40 1 25 1 5 1 Continuous Army Work Table Must be used with Recovery Table
- 27. WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <19 NL ½ NL ½ NL ½ 55 ½ 55 ½ 19–20 NL ½ NL ½ 180 ½ 50 ½ 50 ½ 21–22 NL ½ NL ½ 100 ½ 45 ½ 45 ½ 23–24 <22 <19 NL ½ NL ¾ 75 ¾ 40 ¾ 25–26 22–23 19–20 NL ½ NL ¾ 70 ¾ 35 ¾ 27–28 24–25 21–22 NL ½ 150 ¾ 65 1 30 1 29–30 26–27 23–24 NL ¾ 100 ¾ 55 1 25 1 31 28 25 NL ¾ 80 ¾ 50 1 20 1 32 29 26 180 ¾ 70 ¾ 45 1 20 1 33 30 27 140 ¾ 55 ¾ 35 1 15 1 34 31 28 120 ¾ 50 1 35 1 10 1 35 32 29 100 ¾ 45 1 30 1 10 1 36 33 30 80 1 45 1 30 1 10 1 ≥37 ≥34 ≥31 70 1 40 1 25 1 5 1 Continuous Army Work Table Must be used with Recovery Table
- 28. WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <19 NL ½ NL ½ NL ½ 55 ½ 55 ½ 19–20 NL ½ NL ½ 180 ½ 50 ½ 50 ½ 21–22 NL ½ NL ½ 100 ½ 45 ½ 45 ½ 23–24 <22 <19 NL ½ NL ¾ 75 ¾ 40 ¾ 25–26 22–23 19–20 NL ½ NL ¾ 70 ¾ 35 ¾ 27–28 24–25 21–22 NL ½ 150 ¾ 65 1 30 1 29–30 26–27 23–24 NL ¾ 100 ¾ 55 1 25 1 31 28 25 NL ¾ 80 ¾ 50 1 20 1 32 29 26 180 ¾ 70 ¾ 45 1 20 1 33 30 27 140 ¾ 55 ¾ 35 1 15 1 34 31 28 120 ¾ 50 1 35 1 10 1 35 32 29 100 ¾ 45 1 30 1 10 1 36 33 30 80 1 45 1 30 1 10 1 ≥37 ≥34 ≥31 70 1 40 1 25 1 5 1 Continuous Army Work Table Must be used with Recovery Table
- 29. Continuous Army Work Table Must be used with Recovery Table WBGT °C Light Work Moderate work Heavy work Very Heavy work DPCU Body Armour MOPP4 Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) Work/ Rest (min) Water (L/h) <19 NL ½ NL ½ NL ½ 55 ½ 55 ½ 19–20 NL ½ NL ½ 180 ½ 50 ½ 50 ½ 21–22 NL ½ NL ½ 100 ½ 45 ½ 45 ½ 23–24 <22 <19 NL ½ NL ¾ 75 ¾ 40 ¾ 25–26 22–23 19–20 NL ½ NL ¾ 70 ¾ 35 ¾ 27–28 24–25 21–22 NL ½ 150 ¾ 65 1 30 1 29–30 26–27 23–24 NL ¾ 100 ¾ 55 1 25 1 31 28 25 NL ¾ 80 ¾ 50 1 20 1 32 29 26 180 ¾ 70 ¾ 45 1 20 1 33 30 27 140 ¾ 55 ¾ 35 1 15 1 34 31 28 120 ¾ 50 1 35 1 10 1 35 32 29 100 ¾ 45 1 30 1 10 1 36 33 30 80 1 45 1 30 1 10 1 ≥37 ≥34 ≥31 70 1 40 1 25 1 5 1
- 30. Recovery Table WBGT °C Recovery Time (minutes) DPCU Body Armour MOPP4 <19 15 30 60 19–23 30 60 90 24–26 30 60 120 27 30 60 180 28 30 60 240 29 30 60 360 30 60 120 900 31–32 60 120 NCNP 33 90 180 NCNP 34 120 240 NCNP 35 480 960 NCNP ≥36 NCNP NCNP NCNP
- 31. WBGT °C Recovery Time (minutes) DPCU Body Armour MOPP4 <19 15 30 60 19–23 30 60 90 24–26 30 60 120 27 30 60 180 28 30 60 240 29 30 60 360 30 60 120 900 31–32 60 120 NCNP 33 90 180 NCNP 34 120 240 NCNP 35 480 960 NCNP ≥36 NCNP NCNP NCNP Recovery Table
- 32. WBGT °C Recovery Time (minutes) DPCU Body Armour MOPP4 <19 15 30 60 19–23 30 60 90 24–26 30 60 120 27 30 60 180 28 30 60 240 29 30 60 360 30 60 120 900 31–32 60 120 NCNP 33 90 180 NCNP 34 120 240 NCNP 35 480 960 NCNP ≥36 NCNP NCNP NCNP Recovery Table
- 33. WBGT °C Recovery Time (minutes) DPCU Body Armour MOPP4 <19 15 30 60 19–23 30 60 90 24–26 30 60 120 27 30 60 180 28 30 60 240 29 30 60 360 30 60 120 900 31–32 60 120 NCNP 33 90 180 NCNP 34 120 240 NCNP 35 480 960 NCNP ≥36 NCNP NCNP NCNP Recovery Table
- 34. WBGT °C Recovery Time (minutes) DPCU Body Armour MOPP4 <19 15 30 60 19–23 30 60 90 24–26 30 60 120 27 30 60 180 28 30 60 240 29 30 60 360 30 60 120 900 31–32 60 120 NCNP 33 90 180 NCNP 34 120 240 NCNP 35 480 960 NCNP ≥36 NCNP NCNP NCNP Recovery Table
- 35. Heat Illness and Heat Injury
- 36. Is a spectrum of disorders that arise from the body’s reaction to heat. It includes minor conditions such as heat cramps, heat syncope and heat exhaustion. The core body temperature is usually normal (370 C) and not above 400 C. Heat illness
- 37. Heat Injury = MEDICAL EMERGENCY Prevention through early identification of heat injury symptoms and the immediate treatment of minor heat casualties will reduce the risk of more serious consequences. The onset of heat injury symptoms can be sudden and quickly lead to serious tissue damage or, in extreme cases, death.
- 38. Results from an increase in core body temperature due to exposure to both environmental and internally generated heat. The organs most commonly affected are the brain, muscle, liver and the kidneys. The core body temperature is usually above 400 C and this is a medical emergency! Heat injury
- 40. Danger Response Send for help Airway Breathing CPR Heat Injury Management
- 41. Remove clothing to expose the skin Pour water over the skin, fan vigorously Place casualty in the shade If the casualty is conscious and cooperative give cool water to drink Evacuate to a medical treatment facility in an open vehicle to allow air flow to assist in cooling Heat Injury Management
- 42. Start the day hydrated Keep your fluids up Drink to thirst Hydration
- 43. The colour of urine is a good indicator of how well you are hydrated: IDEAL ↓
- 44. Sometimes known as ‘water intoxication’ this is a medical emergency. Symptoms: – Mental status changes – Vomiting – History of drinking lots of water – Poor food intake – Distended or bloated abdomen – Large amounts of clear urine Beware of Over-hydration
- 45. Responsibilities
- 46. taking reasonable precautions to safeguard your health and safety alerting your Commander of any risk factors that could increase your risk of heat injury YOU are responsible for:
- 47. alerting your Commander if you are feeling unwell during any activity monitoring and taking action when you observe the signs of heat illness/injury in others (i.e. look after your mates). YOU are responsible for:
- 48. Preventing heat casualties through: – allocating sufficient resources (i.e. water, appropriate medical support) – conducting training and operations in accordance with AHI 03 guidelines – investigating heat casualty incidences – learning from incidents to improve heat casualty prevention Commanders are responsible for:
- 49. All heat-related injuries must be correctly recorded on Sentinel Call a spade a spade and do not try to enter or describe a heat illness or injury in a record as something else Disguising the mechanism of injury helps no-one Reporting
- 50. Almost all heat-related injuries are preventable Heat injuries are serious: never under-estimate them Acclimatisation, work–rest periods and good hydration are the ideal preventative measures Beware of ‘water intoxication’ Record heat injuries as heat injuries Summary
- 51. AHI 03—Management of Heat related injuries –Heat injury risk factors –Acclimatisation tables and guidance –Army work tables –Recovery tables Further Info
Editor's Notes
- 1. The Defence Health Manual mandates that heat injury awareness training be provided to all Defence personnel and contractors. 2. To confirm: They must have a broad understanding of signs, symptoms and the management of a heat injury and understand the importance of acclimatisation.
- This slide shows how energy (heat) is transferred in a soldier working in hot weather. These mechanisms are: Radiation- transfer of heat through space from object to object. This can be heat loss OR heat gain Convection- transfer of heat through gases and liquids. Air temp lower than body temp = heat loss from body. Air temp higher than body temp = heat gain to body. Conduction- transfer of heat from object to object through contact. Not usually a factor in considering body heat stress. Evaporation- transfer of heat from liquid to gas by lungs and sweat. Body gets hot, sweats, sweat evaporates. Evaporation is reduced as humidity increases. Evaporation is sometimes the only means the body has to reduce its temperature. Reflection- indirect solar radiation which is reflected off the environment.
- 1. These are some of the factors that put you at higher risk of heat illness and heat injury.
- Activities conducted in heat on consecutive days can cause heat accumulation. This means soldiers may not cool effectively and start the next day with a higher core temperature This means risk of heat injury increases and heat casualties may occur in activities that were previously tolerated
- Acclimatisation is an important step in risk management. Acclimatised soldiers are less likely to fall prey to heat illness and injury.
- See AHI 03 for Acclimatisation tables and guide.
- All units have been issued with both WBGT monitors (“widgets”) and hand-held Environmental Stress Index Monitors (ESIM). The WBGT is a composite index measured in degrees Celsius. It should not be confused with the normal ambient temperature. It comprises three parameters: the Wet Bulb Temperature, the Black Globe Temperature, and the Dry Bulb or ambient temperature combined to provide a heat stress index. When using a monitor, determine the existing local weather conditions at the site of training (the WBGT index) and then read the recommended work-rest table in AHI 03.
- IOT use the Army Work Tables, Commanders must understand the risk management regime required that correlates to the level of risk that will be identified by the Army Work Tables.
- The risk level identified by the Army Work tables will be informed by the level of clothing, the WBGT and the levels of work being carried out. This table provides guidance on deciding how to define the level of work. For example, fire and movement is defined as Very Heavy Work. 2. NOTE: HEALTHMAN uses Very light work, light work, moderate work and heavy work. HEALTHMAN DOES NOT cover ‘very heavy work’!
- This table is designed for up to five hours of work to be conducted with regular breaks. These breaks are designed to allow the body to cool between bouts of work. After five hours of work-rest the recovery table shall be applied (see AHI 03). The work-rest cycle is the ratio of minutes of work to minutes of rest in each one hour period. 3. USE: determine the type of clothing worn, then the WBGT temperature of the activity location and the type of work being carried out. For example, soldiers wearing DPCU in an environment where the WBGT is 31 degrees Celsius, and are doing moderate work (i.e. small arms weapon firing), have a work/rest ratio of 30/30 (30 mins work and 30 mins rest) and a risk injury level of LOW. See example on next slides…
- This is the continuous work table, which is designed for activities where the work rest tables are not appropriate, i.e. specific activities where the duration exceeds the work cycle duration. Any period of continuous activity MUST be followed by the required recovery period as detailed in the Recovery table in AHI 3. When using this table it is intended that there be only two periods of continuous activity in any 24-hour period. See AHI 3. 2. USE: determine the type of clothing worn, then the WBGT temperature of the activity location and the type of work being carried out. For example, soldiers wearing DPCU in an environment where the WBGT is 31 degrees Celsius, and are doing moderate work (i.e. patrolling), are required to rest after 80 minutes – the risk injury level is LOW. See example on next slides…
- In this example the 80 minutes work should be followed by 60 minutes rest (as per the Recovery Table in AHI 3, on next slide) The total continuous work in a 24 hr period should be 2x periods of 80 minutes work (both periods immediately followed by 60 minutes rest)
- The recovery table is to be used with the Continuous Army Work Table Note: Natural Cooling Not Possible (NCNP). When the WBGT is high, the body cannot lose heat through natural methods. Active cooling is required to reduce the body’s core temperature to a safe level. USE: Identify the WBGT temperature of the activity location and the type of clothing worn. From the previous example, the WBGT is 31 degrees Celsius and the soldiers are wearing DPCU and have just completed the 80 mins of continuous patrolling (i.e. moderate work). See the example on next slides…
- 1. Heat cramps are caused by the excessive loss of salt in the sweat of members, who are usually not acclimatised. A key feature of acclimatisation is a reduction in the concentration of salt in the sweat. Heat cramps are easily treated by additional salt in the diet. 2. Heat syncope and exhaustion is the result of the body’s attempts to cool itself by pumping blood to the skin. Enough blood is shunted to the skin that to maintain blood pressure to the vital internal organs the heart must beat rapidly. This leads to a feeling of fatigue and/or collapse.
- 1. The onset of heat injury symptoms (i.e. rapidly rising core body temperature) can be sudden and quickly lead to serious tissue damage or, in extreme cases, death. 2. The most extreme form of heat injury is heat stroke where the core body temperature exceeds 40.6oC. Signs and symptoms include confusion, disorientation or abnormal behaviour. This calls for drastic and rapid cooling and immediate medical assistance. 3. Heat stroke has a 20% mortality rate and a 20% incidence of permanent disability. 4. Heat stroke is a medical emergency.
- If you suspect a soldier to be suffering from heat illness or heat injury start with the basic first aid principle of DRSABC.
- Following DRSABC, attempt to cool the soldier IOT reduce his core temperature prevent any further harm.
- 1. If the water levels in the body are balanced, the urine will be a pale straw or lemonade colour (colours 1 and 2 above). 2. When water loss from the body exceeds water intake, the kidneys will conserve water, making the urine more concentrated and darker in colour. 3. All personnel should monitor hydration status by noting the colour and volume of their urine. 4. Generally, dark yellow urine (colours 6 to 8 above) indicates that you are dehydrated and that you need to increase your water and salt consumption. 5. Consuming vitamin supplements may also produce darker yellow urine.
- Over hydration is caused by drinking large quantities of water in a short time without electrolyte or salt replacement. Over-worked kidneys cannot flush the water out and the blood becomes ‘water logged’. 3. This causes the excess water to enter the body’s cells and cause them to swell. 4. Swelling of cells in the brain cause seizures, coma or a heart attack. 5. As a guide, under most conditions, you should not drink more than one litre an hour. 5. The key to good hydration is to drink before you undertake activities in a hot environment.
- 1. Heat injuries should be described and entered as such in all reporting procedures, records and forms. 2. Appropriate wording is to be used. i.e. “heat illness” – nothing else! 3. This allows Army to continuously improve heat training and treatment.
- 1. We have looked briefly at heat injuries and heat illnesses and the differences between them (i.e. heat injuries occur in casualty’s whose core body temperature is greater than 40 degrees Celsius). You should know how to spot early signs and symptoms of heat-related issues. We have reviewed: individual responsibilities heat risk factors risk management heat injury management reporting. 4. We stress that Army has a zero tolerance of heat injury fatalities during training.
- Stress that AHI 03 is Army’s specific guidance on management of Heat related injuries and planning tables for risk management of activities in the heat.