THURSDAY

I RETURN to day work and begin my week as a "door closer" at one of the least active firehouses in the city.

The reason I'm the door closer is because, according to the doctors I've been to, I have an unstable knee from an on-duty injury and surgery.

Although there are no permanent light duty jobs in the Fire Department, there are approximately 35 to 40 firemen on light duty. Since the city no longer wants to retire members of the Fire Department injured in the line of duty, and all other positions are filled, we close doors.

Getting up at 5:30 a.m. has never been easy, but after a shower, shave and clean uniform I pick up the newspaper at my apartment in Arlington and head for work.

Arriving by 6:30 a.m. I have a cup of coffee and divide the paper among the other firemen, retaining the crossword puzzle for myself, a source of much good-natured verbal abuse from my compatriots.

By 7:30 a.m., I'm back in my car aiming it at the Giant store at Wisconsin and Macomb with a list of two dozen jumbo eggs, two pounds of bacon, one box of quick grits, one loaf of bread, one pound of butter and one and a half gallons of milk for seven hungry hulks.

During my absence, the rookie has raised the flag and written the watch list and assignments in the desk journal. I'm noted as being on light duty and door closer, as opposed to the hook, bar, axe, line or layout man.

After the breakfast, dice are rolled to see who will have to clean the kitchen. The lowest roller is the loser.

Other members go to their clean-up stations. Since we spend two-thirds of our time in this turn-of-the-century firehouse, it has to be kept livable. Sweep, mop and wax the floors, where there is linoleum remaining, that is. The walls are crumbling around us but you may be assured the floors are clean. Polish the brass poles, wash the apparatus, check the hooks, appliances and masks and, everyone's favorite chore, scrub the bathrooms.

Since I'm on light duty, I have no clean-up assignment so I try to stay out of the way, sometimes wasting my quarters in the pinball machine in the basement.

At 8:40 a.m., an alarm comes in for the bank down the street. Brooms, rags, sponges and brushes drop as everyone else runs for the apparatus. I walk to the watch desk, wave goodbye, close the doors and wash the rest of the breakfast dishes.

The engine and truck companies return quickly after resetting the alarm bells. No fire, just a faulty system.

After an otherwise uneventful day, 3:30 p.m. arrives and it's time for me to go home to an early dinner, the news (maybe someone else fought a fire today), then Hill Street Blues and bed.

FRIDAY

We have pancakes and sausage for breakfast and our driver loses the roll of the dice.

The engine and truck go out for a drill and again I wave goodbye and close the doors.

SATURDAY

We have French toast and sausage. The usual complaints were aired about my selection of bread ("Shudda got Wonder.") or sausages ("We had links last time."). No matter what I buy, they'll always eat.

Today is our tillerman's day for doing the dishes.

This being "date night," I take my latest flame (no pun intended) out for dinner and drinks.

SUNDAY

Sleep late after a hard night and three days of getting up so early. Read the paper in bed and don't get up until it is time to get ready for work.

It being a sunny Sunday, I take the long way to work and stop for an ice cream cone.

When I got to work, I am just finishing the cone and the rest want to know where theirs are. That sets me up for a walk to Swenson's after dinner for those who want ice cream or malts.

Dinner is the usual firehouse fare, ''1-2-3," too-well-done roast beef, lumpy mashed potatoes and overcooked green beans. For some reason, most wanted second helpings. Judging by some of the waistlines, most could have gone without altogether.

The rest of the evening is spent slurping ice cream, watching TV, talking, studying, playing the pinball machine or sitting out in front of the firehouse watching people try to pick up the quarter we have glued to a manhole cover.

It's always a good idea to check your bed before you get in it at the firehouse. You never know when someone might have short- sheeted it, put flour or balloons in it or put it up on Coke cans so when you sit down on it in the dark it crashes to the floor.

I like to go up early and try to get to sleep before all the snoring, burping, horseplay and changing of watchmen begins.

At 3:04 a.m., the lights come on and the bell rings. Rousted from an unusually sound sleep in such a way makes my heart jump as firemen rustle up, pull on their turnout pants, pull up the hatch covers and slide down the pole. Then I realize I am not going with them. I get up, walk downstairs and close the doors.

They come back, I go back to bed and reawake at 7 a.m.

MONDAY

I have the day off. I use the time to catch up on some much neglected domestic duties.

This way I don't have to spend my regular three days off cleaning or run- ning errands.

Since my girlfriend doesn't want to go out because she had to get up early for work the next morning, I stay in and read.

TUESDAY

At the firehouse by 3:30 p.m.; go to the store (spaghetti tonight).

Watch the news, talk, read, pinball and bed. Another exciting night.

I get up at 6:30 a.m. for a cup of coffee before driving across town to the Police and Fire Clinic near Blue Plains in Southwest for my monthly visit to the doctor.

WEDNESDAY

I am there at 7:15 a.m; the doctor arrives at 8:40 a.m. Mine is the fifth name on his list of patients. At 9:20 a.m., my name is called. The doctor looks through my file, sees his notes of the previous month and writes anew, "Has unstable right knee. Is unfit for full duty as a fireman. To remain on light duty indefinitely. Return to the clinic in one month."