It is a beautiful day -- bright sunshine and comfortable temperatures. A line of motorcycles stretches out in front of you, thundering along roads dappled in sunlight and leaves.

Suddenly, it happens. As an oncoming vehicle strays across the center line, a bike swerves and goes down. A shower of sparks flies from the sliding machine as it shreds itself all over the road. Everyone pulls over, jumps off bikes and rushes toward their fallen friend. There is shouting and screaming as the scene becomes chaos. And from over the hill, you hear the unmistakable roar of a coal truck headed your way.

Summer is the season for group motorcycle rides. Most times, the rides are smooth and uneventful. But occasionally, it all goes sideways. In those situations, you have to act. But knowing what to do or, just as important, what NOT to do keeps an accident from becoming a tragedy.

Riders could suffer a host of injuries in an accident, head and spinal trauma being the most serious. Fractures, dislocations, lacerations, abrasions (that dreaded road rash), internal and external bleeding are just a few other injuries.

You can prepare yourself for this eventuality by taking an advanced first-aid course and carrying first-aid packs when riding. Urge all riders to wear protective gear, such as gloves, chaps, armored jackets and, yes, helmets. But accidents can happen to even the best prepared rider.

Medical and accident scene experts say there are specific things we can do during the first few moments of trauma's "Golden Hour." But remember that you're neither a doctor nor a paramedic. Do only the minimum necessary to sustain life until help arrives.

1. Secure the scene to keep other vehicles from driving into the accident. Send someone at least 150 feet to either side of the accident to stop traffic. If necessary, go beyond the nearest hill or curve. Assign specific people to the following tasks, and get everyone else off the road and out of the way.

2. Call 911. If this happens in one of those rare places lacking 911 coverage, call the operator, making sure it's a local one. DO NOT YELL. Talk slowly, calmly, and clearly. Don't hang up until the dispatcher tells you to. Give the following information:

• Your name and phone number first, in case you get cut off.

• The type of accident and the number of vehicles involved.

• Location, as accurately as possible. Include the road name or number, which lane, the mile marker, or distance and direction from the nearest town or landmark.

• Number of injured, and if anyone's trapped.

3. Don't turn off ignition keys. This may surprise you, but according to Johnstown police Officer Erin P. Kabler, lead crash investigator, "As an investigator, I would prefer that the ignition not be touched unless absolutely necessary [in case of fire]. We can get a lot of information from the motorcycle prior to the ignition being turned off."

4. Don't disturb the evidence. An accident is a crime scene, almost always involving a violation of the law. Even lifting a fallen bike contaminates the evidence, making it harder for investigators to determine the cause and responsibility. Have someone write down what happened, including names and addresses of witnesses. If moving one of the vehicles is medically necessary, first commit to memory its exact location and position.

5. Don't move the injured unless they're in immediate danger, such as:

• Face down and not breathing.

• Lying under hot metal, or if the vehicle is on fire.

• Lying in a pool of gasoline.

If it is necessary to move the injured, use three to four people. Maintain spinal immobility by log rolling or a blanket drag. Only move the injured the minimum distance absolutely needed. Drag. Don't carry. Take the injured person upslope away from leaking gas and upwind from fire. Don't remove helmet or clothing. If the person is having trouble breathing, loosen his or her collar. Gently support and immobilize the head and neck, as well as any obvious fractures. If the injured party is fully or partially conscious, talk to the person by name. Keep the person awake and aware of the surroundings. Ask the person about his or her medications and write them down.

6. Remember the ABC's of first aid: Airway, Breathing and Circulation. Use approved methods of artificial respiration to keep them breathing. Control bleeding by direct pressure to the wound. Do not use a tourniquet unless a limb is completely severed.

7. Once first responders are on scene, back off. Direct law enforcement to the person who was writing down the particulars of the accident. Only one person should talk. If you know the person's next of kin, give that info to the police. Let the police make the call.

Above all, remain calm. Panic accomplishes nothing except further injury.

When a friend or loved one is hurt, we all want to help. But we must be smart about what we do, or risk doing serious harm.

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