3:15 on a crisp Friday afternoon. A little early for the drunks and the sick children. For the emergency room, you suspect, it'll be a slack time. The nurses will probably be nursing coffee, watching soap operas, grabbing cigarettes on the fly. The calm before the human storm.

So, of course, it's nothing like that at Prince George's General Hospital in Cheverly. Eleven patients sit in the waiting room, shifting impatiently in their seats. Six more are being treated inside. "It never stops," says Chet McPherson, a 23-year-old technician. "Never."

The Prince George's emergency room is strange even by hospital standards.

It has fluorescent lights, brick walls and no windows. Evidently, knowing whether it's day or night would be a distraction.

It has less space than many departments in the hospital, even though it averages ten times the trade in some cases.

It treats six times as many non-emergencies as real ones, and it can't refuse even the most obvious hypochondriacs-it is a public hospital.

Hardest of all, the staff can't exhibit impatient or disdain. And it can't make mistakes, not in this age of sky's-the-limit malpractice payoffs.

So it is a bit like a stock exchange, this sterile, sleek, stainless room. Frantic activity mixed with careful attention to detail. Constant pressure, but a joshing spirit that eases the burden. Yes, indeed, those are bodies on those beds, but times is taken to address them as Tom or Martha or Mr. Smith.

The bottom line is that this emergency room, the largest in the Washington suburbs, does its job and does it pretty well. Here's how job was done crisp Friday: Bum lick

Bum luck is what it was. Maria Jamison, 10, of Bowie, was playing on the jungle gym at school. Whoops! Off she tumbled, onto her left wrist. Her mother has wrapped it in a bag of ice, but even a layman can tell it's broken.

Chet McPherson is cheery and blustery with his young patients. He takes her pulse. "Just want it to make sure you have a pulse . . . .and you do! Congratulations!" Despitethe pain Maria smiles.

Next, he takes her temperature. "It always happens, right?" asks McPherson."They put a thermometer in your mouth and then they ask all sorts of questions."

"Mmmmmmph," grunts Maria.

An hour later, a doctor has set her wrist in a cast, and Maria is ready to go home. She looks a look less scared than she did. Sttill scared

The boy is 17, and he is still scared. His throat is sored, his voice gravelly, and he sniffles a lot. But he is one of the quick ones-10 minutes, a prescription and home.

"Throat culture-$15," says his medical chart. It also says that he has no family doctor and no medical insurance. "He'll never pay this," says Pat Cone, a nurse. "But we have to treat everyone." Worst enemies

Ah, the human race. Talk about being their own worst enemies.

The lady is sitting on a stool, explaining to a doctor why a knuckle on her middle finger is swollen. She was spanking her daughter. The daughter was wearing jeans that were inland with fake rhinstones. Whap! Ouch!

The man arrived at 3:45 p.m. for tests. He thinks he has veneral disease. He also has a job to report to, at 4 p.m. By 5 p.m., he is getting testy. He curses and threatens a nurse. She sternly points out that he might have come earlier; tests take time. The man softens. Then, out of the blue, he asks for her phone number.

Another man wanders up to a bystander and begins speaking very animatedly in a foreign language. The bystanders says he can't understand him. Later, the bystander asks a nurse what language the man had speaking. "His own," she says, pointing at her forehead. "It's a full moon tonight." Awful

Some situations are so awful that one has to turn one's head.

A 24-year-old woman from Lanover lies at the far end of the E.R, her feet toward the wall. She is miscarrying. No one can locate her husband. "I'm so alone," she whimpers. "It is my first baby."

A man, about 50, is wheeled in, filthy from head to foot. He had been test-driving his son's new motorcycle. You guessed it. His left shin is so horribly broken that it's wonder he's still conscious.

"I'm glad it was me," the man says. "If it can happen to me, it can happen to my son. I'm going to sell the damn thing." Human tragedies

But the human tragedies may be worse than the physical.

The E.R. has been alerted. A man was trying to walk across the Beltway near Lanover Road when a pickup truck hit him. As a policeman put it, "His shoes stayed there the rest of him went 150 feet." The man was dead before he knew what hit him.

His wife is brought into the waiting room 15 minutes before the body. She is wailing that special wail. "She been bitten by a dog. They stitch him. A woman has beeneman says.

"What am I going to do?" the woman shrieks, as she is led into the "family room" to get herself together. A priest comforts her. She doesn't notice the body being rolled in, wrapped in a plastic sack. Bee sting

On it goes, toward midnight.

A man has been beaten bloody in a fight. He doesn't live anywhere. He carries all his earthly goods with him in a bowling bag.

A child has seen bitten by a dog. They stitch him. A woman has been stung by a bee. They lance the string, and stitch her. A warehouseman has run over his own foor with a dolly. He is X-rayed and released.

Susan Ross, 32, nurse, bustles past."It's not exactly Pisces (an "in" Washington night club), but what else are you going to do on a Friday night?" she asks. 'Pretty normal'

11:30. End of shift. There have been 103 customers in eight hours, about average, according to Dr. George C. Hajjar, the E.R.'s physician director.

There have been 27 upset stomachs, 14 backaches, three car accidents and one epileptic fit. There have been 15 cases of flu, eight cases of mental disorder, six cases of plain old falling-down drunkness and one case of heart spasms.

One man died and one woman miscarried. A three-year-old swallowed some cold capsules; a three-year-old girl skinned her knee. A 54-year-old woman had a stroke; a 55-year-old man had an ulcer attack.

"Pretty normal," said Mike Friedman, the assistant head nurse,"Tomorrow's when it gets busy."