Day in the San José mine begins at 7.30am, when a makeshift lighting rig powered by truck batteries and a portable generator flickers into life, casting a weak light on the refuge where the men have now spent 35 days.

In the hours after the shaft was sealed the miners used truck headlights to light their way, but in the following days, electrician Edison Pena wired up a series of lamps which provide between eight and 12 hours of light to provide a semblance of day and night.

"In those first few days, he took care of all the illumination down there, they had some equipment in there. It was never dark," said Pedro Campusano, a nurse with the rescue operation who has regular contact with the miners. "They had some machinery including a pickup, a truck, so he installed an electrical [generator] to feed the lighting system."

Breakfast begins to arrive at 8.30am via a delivery system known as the "pigeons" – the three-metre metal tubes that are packed with food, medicine and letters and lowered 700 metres through a 8.8cm communications shaft.

The food takes over an hour to arrive, with deliveries every 20 to 30 minutes. At the bottom of the mine, three men are tasked with receiving the "pigeons," unpacking bottled water, hot sandwiches and morning medicines, then stuffing the latest letters and messages into the torpedo-shaped tube, which slowly rises out of sight.

After breakfast the men clean their living area. "They know how to maintain their environment. They have a designated bathroom area, garbage area and are even recycling," said Dr Andre Llarena, an anaesthesiologist with the Chilean navy. "They put plastic stuff away from biological [wastes], in different holes. They are taking care of their place."

Morning showers require the men to climb aboard a bulldozer-type mining vehicle that rumbles 300 metres up the tunnel to a natural waterfall where they shower, shampoo and clean off the ubiquitous rust-coloured mud.

Showers and breakfast are followed by morning chores, some under instruction from mining engineers above ground, others in obedience to common sense.

Last week the trapped men sent up a list with a job description for each of them. "We have three groups, 'Refuge', 'The Ramp' and '105' [metres above sea level]," wrote Omar Raygada in a letter to his family. "I am head of Refuge."

Each group leader reports directly to Luis Urzua, the shift foreman on 5 August, when the men entered the mine in northern Chile for what was expected to be a half-day shift. Each has a variety of jobs which must be completed before the eight-hour turn is over.

"These men are trapped in their office – they are not tourists who went cave visiting. They know the drill, know how to get around," said Llarena. "They regularly spent 10-12 hours down there in the heat and humidity, and that's what they're doing now. That's what psychologists are reinforcing – this is a long shift, a very long shift, but still a shift."

Nineteen-year-old Jimmy Sanchez, the youngest of the group, is the "environmental assistant", who roams the caverns with a handheld computerised device that measures oxygen, CO 2 levels and air temperature, which usually averages at around 31C. Every day Sanchez takes the reading from the gas detector and sends his reports to the medical team outside the mine. Another group of men reinforce the mine walls and divert streams of water seeping into their refuge. Several of the drilling and communications tubes connecting the men to the surface use water as lubricant, meaning a constant stream of muddy gunk trickles into their world.

Throughout the morning, some of the men maintain regular security patrols to scan the perimeter of their sleeping and living quarters, alert for signs of another rockfall. Others spend hours working with long-handled picks to lever loose large rocks that threaten to fall from the ceiling.

What the miners most fear is that a small rockfall could suddenly trigger a full-scale collapse, leaving them trapped in an even more confined space.

"They will seek shelter at the first major movement [of rocks]," said Alejandro Pino, a lead organiser of the rescue operation who works for the Association Chilena de Seguridad [ACHS]. "These are experienced miners – at the first sign of major movement they know where to hide."

The relief bore that will allow the men to escape is still some 140 metres from the living quarters, but in around three weeks' time a much larger drill bit will start tearing through the ceiling of the chamber, and the men will need to start moving an estimated 500kg of rock and mud every hour as debris from the drilling drops from the roof.

Food deliveries and meals take up much of the day. Lunch delivery starts at noon and takes a full hour and a half to deliver the hot meals.

"When they finish lunch, they have a general meeting, and in this meeting they start their prayers," said Dr Jorgé Diaz, a member of the rescue team.

The daily prayer is organised under the leadership of José Henriquez, who has been named the group's official "pastor". If Henriquez wants to record his sermons, he has the media team of Florencio Avalos, the group's official cameraman, and two sound engineers, Pedro Cortez and Carlos Bugueno. Aside from sermons, the sound engineers are also in charge of maintaining the phone lines, both conventional and fibre-optic. Telephone conversations and now video conferences are often scheduled for the early afternoon.

With basic needs such as food and sleeping quarters now fully organised, the men have also chosen to fill both bureaucratic and cultural positions. Victor Segovia is the group's official biographer, penning daily accounts from day one in an effort to keep an ongoing log of the men's predicament.

In a nation that produced the Nobel prize-winning poets Gabriela Mistral and Pablo Neruda, it is only briefly surprising that the men named Victor Zamora as the group's official poet. Zamora's rhymed compositions are often one-page homages to the rescue team. Zamora's combinations of hope, gratitude and humour are among the most-read messages from below. Even after multiple readings, the poems still brings tears to the eyes of Campusano, the nurse working topside: "When this first came up, I read it and got halfway through, I couldn't." Campusano's eyes fill with tears. "It fills me with emotions … when I read it."

After lunch, the men are free to relax. Many of them spend the afternoon writing letters to their families, using safety lamps attached to their helmets. Letters from the men are frequently stained with rusty red blotches, a permanent reminder of the 85% humidity and muddy conditions inside the mine. The men have requested books, sketchpads and a stereo to play music.

Medical rounds are conducted daily by Jonny Barrios, a miner who trained in advanced first aid. Barrios once dreamed of studying medicine, but probably never envisaged how that ambition would be realised: as the team's official doctor, he is now undergoing a crash course in distance learning.

With fungal infections and bad teeth at the forefront of current medical problems, Barrios is under strict orders to make a daily list of any health problems.

In recent days, dermatological infections, toothaches, constipation and withdrawal from tobacco addiction have also caused problems. When a miner is considered ill, his name is added to those who have been "transferred" to a category known as the "intensive care unit". Barrios is so busy taking temperatures, administering medicines and updating patients' charts that he has now brought in Daniel Herrera, who has been given the title "assistant paramedic".

Of all the men given the job of keeping the group functioning, Barrios is perhaps the most crucial. He has already vaccinated the entire group against diphtheria, tetanus and pneumonia.

"We need him to measure the men, we need their circumference [in order to find out if they will fit through the small rescue hole now being drilled]," said Dr Devis Castro, a surgeon who has carried out advanced studies in nutrition. "The only way to weigh the men is with one of those scales like you see at the fruit market. So we are designing one small enough to send down through the tubes. Then they are going to have to figure our a way to hang themselves from the hook."

Apart from the daily medical rounds, Barrios has a daily hour-long consultant call every afternoon in which he receives messages from Chilean government's medical team, who huddle around a phone the size of a briefcase in a small tent some 700 metres above the trapped men.

"Jonny, can you hear me?" yelled the Chilean health minister, Dr Jaime Manalich, during a medical conference call last week. "Jonny, have you ever pulled out a tooth?"

From far below came the crackle of Barrios's voice. "Yeah … one of my own."

"If we have to ask you to pull a tooth and send you sterilised equipment, could you?" asked Manalich, who promised to first send a how-to video showing Barrios the most professional way to rip out an infected molar. "Remember Jonny, tell the men if they don't keep brushing their teeth that you will soon be ripping their teeth out down there."

From the moment the men were trapped on 5 August, the miners organised themselves for a rescue they guessed would be many days away, said Dr Jorge Diaz of the ACHS medical support team. "These are thinking people, they are workers with a work ethic that goes back many years. They don't need us to tell them what to do."

With the three shifts functioning like clockwork, psychologists have begun permitting certain extra pleasures. Earlier this week, the 33 miners gathered to watch their first live football match: Chile lost to Ukraine, 2-1. But despite the mud underfoot, loose rocks threatening to crash down and a lacklustre match, the men cheered every moment. Former football star Franklin Lobos, a legend on the pitch for the northern Chilean team Cobresal, ran a play by play summary.

After the match was over, the men prepared to sleep. They walked down the ramp to the bathroom, an area kept constantly clean by a stream of fresh water that washes away the urine and faeces.

By 10pm, the lights are out, and the men prepare their beds – inflatable mattresses shipped down from above. As they drift off to sleep, they are assured that if nothing else, their saga has been shortened by one day.