Royal Army College

Lesson Overview

A team on a task is kept going by a short list of commodities that keep the human body alive and working: clean water, enough food, and the rest and care that let people carry on. Of these, water comes first. A person can work for some days without food, but only hours without water before judgement and strength begin to fail, and in heat the margin is shorter still. So the planner of any sustainment task begins with water, then rations, then the welfare of the people doing the work, because a force is made of people, and a force whose people are dehydrated, underfed, or worn out has stopped helping whether it knows it or not. This lesson teaches how to plan those commodities by the number of people and the number of days, the figures to plan from, and why all of it must be safe to drink and eat.

It teaches the planning to two ends at once. The first is the team's own effectiveness: a member short of water tires fast, thinks slowly, and makes the errors a fresh member would not, and the same is true, more slowly, of one who is underfed or exhausted. The second is the people the force serves, because on a relief task the water, the hot meal, and the dry place to rest are among the most valuable things the Army carries, and getting them there in the right quantity is the help itself. A tired, cold, hungry team cannot do that work, so its own welfare is not a comfort set against the mission but a part of the mission.

This is the knowledge layer. The treatment of a treatment system, the recognition and care of a dehydrated or heat-injured person, and the practice of food and field hygiene are taught and certified in person in MED 210 Field Health, and the hands-on storekeeping and issue of these commodities is practised and signed off in person where supervision allows; this lesson teaches the planning and the principles on which that work rests. By the end you will be able to state the daily water a person needs for life and for full field living and plan a task's water by people and days, explain why water and food must be safe and how that ties to MED 210, plan rations by people and days and describe what a field ration is, and explain why rest, morale, and welfare are part of sustainment and how to plan for them.

Key Terms

Drinking water requirement: the water a person must take in by mouth each day to stay alive and effective, roughly 2.5 to 3 litres a day at rest in temperate conditions and several litres more in heat or under hard work.
Full water allowance: the larger figure that covers drinking, cooking, and personal hygiene together; the Sphere relief planning figure of about 15 litres per person per day is a useful benchmark.
Sphere standard: the recognised humanitarian benchmark for the minimum a person needs in a relief setting, used here as a planning figure for water.
Potable water: water that is safe to drink, either from a clean source or made safe by treatment; the only kind that should ever reach a person's bottle or pot.
Field ration: a packaged, calorie-dense, keeping ration designed to feed a person for a stated period in the field without refrigeration or a kitchen.
Ration scale: the planned issue of food per person per day, from which a task's rations are worked out by people and days.
Food hygiene: the discipline of preparing, storing, and serving food so that it does not make people ill; a catering responsibility tied to MED 210.
Welfare: the deliberate care of the people doing the work, their rest, food, warmth, and morale, planned as part of sustainment because a worn-out team is an ineffective one.
Consumption rate: how much of a commodity a person or team uses in a set time, the figure all this planning is built from.

Water comes first

Of every commodity a team carries, water is the one the planning starts with, because the body fails fastest without it. A person at rest in temperate conditions needs roughly 2.5 to 3 litres of drinking water a day simply to replace what the body loses through breath, sweat, and urine and to stay alive and clear-headed. That is the floor, and it is a floor for a person doing nothing in mild weather. The moment the work is hard or the weather is hot, the figure climbs, and it climbs steeply: a member working through a hot day can lose several litres more in sweat alone, and the drinking requirement can reach five, six, or more litres in a day. Heat and effort, not thirst, are the guide to how much a team will drink, because thirst lags behind the loss and a busy member often does not feel it until they are already short.

Dehydration is dangerous out of proportion to how mild it feels. Losing even a small fraction of the body's water saps strength and, worse, dulls judgement, so a dehydrated member tires quickly and begins to make the small errors that a sustainment task cannot afford. In heat, dehydration is also the road to heat illness, which is a medical emergency. The planner's defence against all of this is to plan generously, to err on the side of more water rather than less, and to plan resupply so that it arrives before the team runs short, never after. Running out of water is not an inconvenience to be endured to the next delivery; it is a sustainment failure that takes the team out of action.

A planner must hold two figures in mind, because they answer different questions. The drinking water requirement answers "how much must each person drink to stay alive and effective", and it is the figure that matters when the only question is keeping people going, for example a section carrying its own water on a short task. The full water allowance answers "how much water does a person need for proper field living", because people do not only drink: they cook, they wash, and on a longer task that hygiene is what keeps them healthy. For the full allowance the Sphere humanitarian standard gives a sound planning figure of about 15 litres per person per day for drinking, cooking, and personal hygiene combined. That figure is drawn from relief work, where it is the benchmark for the minimum a person in need should receive, and it serves equally well as the figure for what a relief task must deliver to the people it serves.

  WHICH WATER FIGURE TO PLAN FROM

  Question being asked                         Plan from
  -------------------------------------------  --------------------------
  How much must each person DRINK to stay      2.5 to 3 L/person/day
  alive and effective, at rest, temperate?     (the survival floor)

  Same, but in heat or under hard work?        5 to 6+ L/person/day
                                               (climbs with heat/effort)

  How much for full FIELD LIVING: drinking     ~15 L/person/day
  plus cooking plus personal hygiene?          (Sphere planning figure)

  How much to DELIVER to people on a relief    ~15 L/person/day
  task (the people we serve)?                  (Sphere minimum)

  Rule: plan generously, and resupply BEFORE the team runs short.

Planning water by people and days

Water, like every commodity in this course, is planned from the same two numbers: how many people, and for how many days. Multiply the daily figure per person by the number of people and by the number of days, and the answer is the water the task needs. Then add a margin, because plans slip, days run long, and the heat is often worse than forecast. A planner who works to the exact figure and no more has planned to run out on the first hot afternoon or the first delay.

Take a worked example. A section of eight is to spend three days on a task in warm weather, carrying and being resupplied with its own drinking water. Plan from the higher drinking figure for warm, working conditions, say 5 litres per person per day. Eight people times 5 litres times 3 days is 120 litres of drinking water, before any margin. Add a sensible margin of a fifth and the figure is about 144 litres to plan, source, and move. That is a real load, and seeing it on paper is exactly the point: it tells the planner this much water must be carried or delivered, and it forces the question of how, which is the work of Lesson 05 on transport and load planning.

The table below sets the two figures, the drinking requirement and the full Sphere allowance, against people and days, so that a planner can read off the rough quantity for a task at a glance. It is a planning aid, not a substitute for working the sum for the actual conditions.

  WATER PLANNING TABLE  (litres, before margin)

  DRINKING ONLY  (plan ~3 L/person/day temperate; more in heat)
                 1 day    3 days   7 days
   1 person        3 L      9 L      21 L
   4 persons      12 L     36 L      84 L
   8 persons      24 L     72 L     168 L
  20 persons      60 L    180 L     420 L

  FULL FIELD LIVING / RELIEF DELIVERY  (~15 L/person/day, Sphere)
                 1 day    3 days   7 days
   1 person       15 L     45 L     105 L
   4 persons      60 L    180 L     420 L
   8 persons     120 L    360 L     840 L
  20 persons     300 L    900 L   2,100 L

  Then ADD A MARGIN (a fifth is a sensible start), and plan UP
  the drinking figure for heat or hard work.

Water must be safe

A quantity of water is only useful if it is safe to drink. Water that carries disease will put more people out of action than thirst would have, and on a relief task unsafe water handed to people in need does harm in the name of help. So the planner's question is never only "how much water" but "how much safe water", and the two are planned together. Water comes either from a source already clean and trusted, such as a treated mains supply or bottled stock, or from a source that must be made safe by treatment before anyone drinks it.

The methods and the judgement of treating field water, boiling, filtering, chemical treatment, and how to tell when each is needed, are taught and certified in person in MED 210 Field Health, and a logistician does not improvise them. What the logistician must do is plan for them: if the water source is not already potable, then the means of treatment, the filters, the tablets, the fuel to boil, become commodities in their own right and are planned by consumption just as the water is. A plan that delivers 144 litres of untreated water and no means of treating it has not delivered drinking water at all. The two courses meet exactly here: MED 210 makes the water safe, LOG 210 makes sure the means to do so are present in the right quantity, and the team drinks safely because both were planned.

Rations: feeding a force by people and days

Food is planned on the same principle as water, by people and by days, from a planned daily issue per person called the ration scale. Decide how many people are to be fed and for how many days, multiply, add a margin, and the answer is the rations to source and move. The arithmetic is the same as for water, and so is the discipline: plan generously and resupply before the team runs short, because hungry people, like thirsty ones, lose strength and clarity.

For the field the ration of choice is the field ration: a packaged, self-contained ration designed to feed a person for a day, or a meal, in the field without a kitchen or refrigeration. A good field ration has two qualities the planner depends on. It is calorie-dense, because field work, carrying loads, and cold all burn energy fast, and an underfed member tires and chills more quickly; the field ration is built to deliver a full day's energy in a package light enough to carry. And it keeps, because it must survive storage and movement without refrigeration and still be safe and palatable when it is opened. Those two qualities are why field rations, not fresh food, are the staple of a task: fresh food feeds people well at a base with a kitchen, but it is heavy, perishable, and needs cooking, while the field ration goes in a pack and waits until it is needed.

  RATION PLANNING AID  (per person per day = one day's ration)

  PEOPLE  x  DAYS  =  rations to source   (then + margin)

  e.g. 8 people x 3 days  = 24 day-rations  -> + margin ~5 = ~29

  CHOOSE THE RATION TO THE TASK
  -----------------------------------------------------------------
  Field ration      calorie-dense, keeps, no kitchen   the field
                    needed, eaten hot or cold          staple
  Fresh / cooked    feeds well, needs kitchen, heavy,   a base with
                    perishable                          a kitchen
  -----------------------------------------------------------------

  ALWAYS PLAN ALONGSIDE THE FOOD:
   - water to cook and drink with it      (see water table)
   - the means to heat it, and fuel       (see Lesson 04)
   - food hygiene in preparing/serving    (tie to MED 210)

When food is prepared and served for a team, rather than each member eating an issued ration alone, catering and food hygiene become a sustainment responsibility. Food prepared or stored badly will make a team ill, and a team laid low by an upset stomach is as surely out of action as one that has run out of rations. The standards of clean preparation, safe storage, and safe serving are taught and certified in person in MED 210 Field Health, and the logistician plans so that they can be met: clean water to prepare and wash with, the means to keep food at safe temperatures, and a clean place to work. Here again the two courses meet: MED 210 sets the hygiene standard, LOG 210 plans the water, fuel, and stores that make meeting it possible.

Welfare is part of sustainment

It is tempting to think sustainment ends at water and rations, the things that go in the body, and that rest and morale are a softer matter for the team to sort out among themselves. That is a mistake, and an expensive one. A tired, cold, hungry team is an ineffective team, and no quantity of correctly delivered stores changes that. The whole point of sustaining a force is to keep its people able to do the work, and people who have not slept, who are chilled, or who are losing heart are not able, however full the ration store. So the welfare of the team, its rest, its warmth, and its morale, is planned as deliberately as its water, because it is sustainment by another name.

Rest is the clearest case. Fatigue degrades judgement and strength as surely as dehydration does, and a team driven without rest will begin to make errors, miss things, and eventually stop being useful, no matter how willing its members are. A sustainment plan that runs people without a plan for sleep and recovery is planning to fail at the far end of the task, just as surely as one that runs out of water. So rest goes into the plan: a routine that lets people sleep, work shared out so that no one is run into the ground, and the simple provision, a dry place to lie, a hot meal, a warm drink, that lets tired people recover.

Morale follows from this and feeds back into it. People kept fed, watered, warm, and rested keep their spirits, and people whose spirits hold keep working through hardship that would break a neglected team. The small things the logistician can provide, the hot meal at the end of a cold day, the brew at a halt, the dry socks, the post or the means to contact home, do work out of all proportion to their weight, because they tell the team it is looked after and worth looking after. None of this is comfort for its own sake; it is method, and the method keeps the team in action. The leader and the logistician plan it together, the leader judging the people, the logistician providing the means, and between them they keep the force fit to do the work.

In Practice: A two-day field clinic resupply

A relief task is set: a small field clinic is to run for two days in a generic rural location, staffed by a team of six, serving an expected eighty people a day who come for care. The Quartermaster NCO is asked to plan the water, rations, and welfare. She begins, as the lesson says, with water, and she separates the two questions. The clinic team of six needs water for full field living, drinking, cooking, and the hygiene that a clinic above all must keep, so she plans them at the Sphere figure of about 15 litres each per day: six people times 15 litres times 2 days is 180 litres for the team. The people coming for care will be there only briefly, so for them she plans drinking water and water for the clinic's own use rather than a full daily allowance each, and she works that figure with the clinic lead. To both totals she adds a fifth as a margin, and she notes on the plan, in red, that the local water source is untreated, so the means of treatment, filters and the fuel to boil, are demanded as commodities in their own right, with a line to MED 210 who will run the treatment and the food hygiene.

Rations next, by people and days: six staff times two days is twelve day-rations of field ration, plus a margin, calorie-dense and keeping so they survive the move and need no kitchen. She plans the water to cook and drink with them inside the water figure, and the means to heat them, with fuel, against Lesson 04. Then, before she closes the plan, she does the thing a hurried planner skips: she plans the team's welfare. A clinic that runs two days flat out will wear its six people down, so she builds in a rest plan, with the staff working in turns rather than all six straight through both days, a dry covered place for those off shift to lie down and get a hot meal and a warm drink, and she earmarks a little spare fuel for brews at the halts. She writes one line at the top of the plan, "a tired team treats badly", and it carries the argument: the rest and the hot drinks are not indulgence, they are what keeps the clinic treating well into the second day. Her plan delivers safe water in the right quantity, rations that keep, and a team still fit to work at the end, and the help gets done.

Check Your Understanding

A section of ten is to work for two days in hot weather, carrying its own drinking water. Using a planning figure of 5 litres of drinking water per person per day for hot, working conditions, how much drinking water should be planned before any margin, and why is a margin then added?
Explain the difference between the drinking water requirement (about 2.5 to 3 litres a day at rest in temperate conditions) and the full Sphere field allowance (about 15 litres per person per day), and give one situation in which a planner would use each.
Why are rest and morale treated as part of sustainment in this lesson, and not as a separate, softer matter for the team to manage on its own?

Reflection (write a short paragraph): Think of a time you were tired, hungry, thirsty, or cold while trying to do a job. How did it affect the quality and care of your work, and what would have made the most difference? Relate your answer to why this lesson plans a team's welfare as deliberately as its water and rations.

Summary

Water comes first: a person needs roughly 2.5 to 3 litres of drinking water a day at rest in temperate conditions, and several litres more in heat or under hard work; dehydration saps strength and judgement before it is felt.
For full field living, drinking plus cooking plus hygiene, the Sphere humanitarian figure of about 15 litres per person per day is a sound planning benchmark, and it is also the figure for delivering water to people on a relief task.
Plan water and rations the same way, by people and by days, then add a margin, and resupply before the team runs short, never after.
Water and food must be safe: treatment of water and food hygiene are taught and certified in person in MED 210 Field Health, and the logistician plans the means to meet those standards.
Field rations are calorie-dense and keeping, the field staple; plan alongside them the water, the means to heat, and the fuel they need.
Welfare is sustainment: a tired, cold, hungry team is ineffective, so rest, warmth, and morale are planned as deliberately as water and food.
Cross-references: builds on LOG 201 and LOG 210 Lesson 01 (Sustaining a Force in the Field) and Lesson 02 (Resupply and the Demand Cycle); leads to Lesson 04 (Power, Fuel, and Batteries) and Lesson 05 (Transport, Load Planning, and Movement); ties closely to MED 210 Field Health (safe water, food hygiene, medical care) and to HCR 201 / HCR 210 for the fair distribution of relief.

Water, Rations, and Welfare