He was among the first of about 1,000 firefighters who fought the blaze at the warehouse owned by Ruihai International Logistics in the industrial Binhai New Area on Wednesday night, shortly before two massive explosions.

Zhou is said to be in a stable condition, state television reported, citing hospital doctors.

Zhou was sent to Teda Hospital with burns to his face and lungs, and cuts down to the bone on his left leg. Doctor Shen Qiang said he was conscious but had no recollection beyond the blast. "Captain, has the fire been put out yet," Zhou was quoted as saying when he regained consciousness. "How's everyone else?" he said. But none from his team have survived.

READ MORE: In pictures: Huge explosions in Tianjin leave dozens dead, injured

A fire department chief whose team found Zhou, who appeared visibly moved, told state television that the firefighter had a strong will to survive.

He said his team had revisited an area of the blast site on Friday morning it had not been able to search properly last night as fires were still burning.

At least 17 firefighters were killed tackling the huge blaze, state media reported. Many others are missing.

Families in despair

The families of missing firefighters are waiting at hospitals to identify bodies. Most fire crews are usually aged between 19 to 22, according to relatives.

Family members have said that the first firefighters to the scene came from one brigade and only two are thought to have survived.

Families of missing firefighters gathered at Teda and Tianjin Port Hospital, eager for any news about their loved ones. When asked about their sons or nephews, tears would well in their eyes.

According to figures released by authorities yesterday, 22 firefighters are confirmed dead and 13 remain missing. At least 68 firemen are injured. But families are suspicious of the figures. The number of names on the "missing list" at the Teda Hospital alone far exceeded 20.

Frustrated by the official silence, families exploded in anger and tears of desperation. When one person began to cry or shout, others would become emotional too. "I used to be really tough, hardly cried," Peng Jiuling told theSouth China Morning Post. His nephew, 22-year-old firefighter Peng Debao has been missing since the blast. "But now, looking at that crying woman makes me want to cry too."

Peng belonged to the port fire department's No. 4 team, many of whom came from the same hometown of Jixian. Two have been found alive, including 26-year-old Liu Bin. He is being treated at Teda Hospital's intensive care unit after the blast wave crushed his spleen and broke his ribs, which punctured his lung.

Three other firefighters are being cared for in the same ICU. Liu's father Liu Jinliang, 47, considers his son a lucky man. The blast happened when he went back to the fire truck to attach a hose to a new tank of water. That extra distance saved his life.

The firefighters initial response remains clouded in controversy. A fireman told the Southern Weekly that after pumping water at the fire for more than 10 minutes, there were small blasts followed by the first deadly one. He said the more than 100 firefighters who arrived in the first batch weren't informed the chemicals were more dangerous if they came into contact with water.

The Global Times reported that when the port's fire department received the alarm, they weren't told dangerous chemicals were involved. It was described as a normal civilian case even though crews were trained and equipped with special gear to handle chemical explosions.

Xinhua said the disaster has claimed the most number of firefighters in a single incident since the founding of the People's Republic of China in 1949.

Reading that news and looking at the dirty boots taken from his injured son, Liu Bin's father gave a long sigh. "He chose this job, so he can't say no to a command. He can't and shouldn't question it. He is lucky."

Further chemical risks

Officials said on Friday that the scene of the explosions was still dangerous for firemen as dangerous chemicals stored in the warehouse could still trigger further blasts.

About 700 people are receiving treatment in hospital after the huge explosions rocked the city on Wednesday night, shattering windows several kilometres away from the centre of the blasts.

Troops trained in chemical warfare have entered the site to check out what dangerous substances remain, state media reported.

The authorities are considering whether to send teams into the core of the blast site on Friday to remove remaining hazardous materials in the area, state television said.

The environmental ministry has found traces of cyanides and other chemicals in two underground drainage systems three to eight times safety limits, the report said.

A Tianjin environment department official told reporters at a press briefing that all drainage outlets in the area have been shut to contain any polluted water.

Media in China have continued to question why the giant hazardous goods warehouse was allowed to operate so close to homes and other public buildings in the area.

Tianjin officials said at the press conference that Ruihai International Logistics’ warehouse was allowed to store hazardous goods for only 40 days while they were in transit, including gases and liquids.

They said company records were destroyed in the explosions and fire and the authorities had difficulty finding out exactly what was stored in the complex as firefighters attempted to tackle the blaze.

They are now trying to compile a list by going back through customs records.

Firefighters were pulled out of the area briefly on Thursday morning because of fears over their lack of knowledge of what dangerous substances they were dealing with.

Additional reporting by Zhuang Pinghui and Mimi Lau