"What you do could be life-saving. You are essential and intrinsic to what we do here. Without you there is no racing, no grand prix." It is a rallying call the audience of 350 scarcely requires. These are the converted, the committed; train-spotters, some would say. These are motor racing marshals.
Just like the millionaire drivers, these volunteers have their training days. Some here are novices, most are on refresher courses. They pay their own way and for their overalls, which can cost pounds 70. Their allowance for the three days of last year's British Grand Prix meeting was pounds 10. They may be in for an increase at this year's four-day event.
But then, as they tell you, this is their hobby, it's what turns them on. You suspect them to be frustrated motor racers. "No, just nuts about the sport," most insist. A middle-aged woman, who has been a marshal for six years, says: "I want to be involved and put something back into the sport. That sounds altruistic, but it's true."
They put something back - waving warning flags, extinguishing fires, dragging stricken cars from gravel traps and controlling crowds - at circuits up and down the land. A thousand of them will be on duty at the grand prix here in July.
High summer seems as distant as the next British world champion as instructors from the marshals' club take groups through their specialised tasks. Out in the country, exposed to the full venom of the elements, fire-fighters tackle a burning car. A women of modest stature and a boy of 16 - the minimum age for a marshal - are among those who attack the flames with growing belief. Around 20 per cent of marshals are female.
Back in the classroom, the groups settle for instruction and an exchange of opinions. They range from a "gold" man with 30 years experience to "greys" and novices. They are preached the virtues of customer care, the customer being the driver, team member, organiser and spectator. "We are like referees." In other words, they get it in the neck from all sides.
"You've got to look interested even if you want them to bugger off. We've travelled miles, paid to get there, we're soaking wet, tired, crap food, but we do it because we love it. We have people from different jobs, from a cross-section of the community, but here we are teams and marshals who meet at weekends. Please don't think we are cliquish or weird. We're pleased to see more ladies."
That last remark is directed at two slightly nervous looking novices. Their apprehension becomes more acute with further recollections of encounters with difficult "customers". "I do not expect someone to call me a something cow. Not because I am a woman, but because I am a marshal. Some are offensive." The gold man chimes in: "You've got to be thick-skinned. It's down to experience. One of the pits, not here, is a Stalag 17 job. Even I was shocked." The woman marshal comes back: "I know they are under stress, but I can accept only a certain amount from them, not abuse."
A male marshal with a long memory recounts: "Stirling Moss asked where his Ferrari was and was told to sit down in the corner and shut up. And he did." Another marshal: "There's a certain lady, who is the exception, who tells you to eff off. What do you do?" A colleague proffers a solution: "You've had your fire training - aim at her." One of the novices, by now perplexed, asks: "What are these complaints?"
Someone leaning casually in the corner responds: "Why can't I do that? Why can't I go there? Why am I disqualified?" The gold man comes to the rescue. "Don't think it's so bad. It's fun. These are the negative sides. Don't take it personally, just get it sorted."
After lunch another group is digesting procedural guidance in the event of a major incident. Team discipline is declared essential. "The last thing we need is heroes." At the scrutineering bay, the rescue crew demonstrate their efficiency with cutting equipment. They can remove the roof of a touring car in five minutes. "If we can't get a driver out, no one can."
Heroes or not, British marshals are content to perpetuate the claim that they are the best trained and regimented in the world. A former chief incident officer, battle-weary and scarred, says: "I don't think some team managers would realise we are here today - or even care."
Gary Dearn worked his way through the ranks to become the present chief incident officer here and his wife, Pam, from the banks to the control tower. "There's more enjoyment at club meetings than grand prix meetings. The grand prix is the pinnacle and everyone is drawn by the speed and hype. But to be honest, it's not worth the hassle and the bull," he said.
The expansion of the grand prix meeting to four days loads still heavier demands on the shoulders of the volunteers, but a full complement has been assigned and already they are planning their minimum requirement of 15 days' service this season to qualify for the big race next year. As long as they have their thick skins and packed sandwiches, motor racing in this country is in safe hands.