Beijing health officials are promoting a blood drive to ensure there is an adequate supply of a type of blood that is far more common among non-Asians. It is the latest in a long list of preparations that the city is making as it gets ready for the 2008 Summer Olympics.

A 2008 Beijing Olympic Games blood donation poster is displayed in Beijing, 11 Nov 2007

Beijing is in the midst of an Olympic blood drive.  Advertising posters line inner city bus stops shelters and are plastered on subway station walls.

The city has a shortage of Rhesus, or Rh-negative blood - a strand rare in China, with only three of every 1,000 Han Chinese being Rh-negative.

China expects around 500,000 foreign visitors to come to Beijing during the Olympics.  Roughly 15 percent of Caucasians, and 10 percent of black Africans are Rh-negative, a large portion of those who will make up a majority of tourists during the Games.

Rh refers to an antigen that humans either have or do not have on the surface of their red blood cells. Those who have it are Rh positive. Those who do not are Rh negative.  It is important in transfusions that both donors and recipients have the same types.

Zhu Ruiquan of the Beijing Red Cross says he needs extra supplies of the blood to cover the increase in visitors expected in the city during the games.

"We need to get prepared for them in case there are some accidents or some problems, so we are ready to handle them," he said.

Zhu's organization has set up mobile blood centers across Beijing to help to collect 16 liters of Rh-negative blood that he wants to have on standby for the Olympics.

Many Chinese are motivated to donate blood because, with China's user pays medical system, donors receive blood transfusions for free.

Yet the need to cater to foreigners's blood type for the Olympics has prompted even more people, those like like Gao Xiaoyang, to donate.

"Donating blood is the duty of every citizen, also by donating blood we can help build a better Olympics. It is how we can contribute to the Olympics in our own way," he noted.

But Red Cross nurses say some Chinese are reluctant to give their blood.  They remember a commercial blood-selling scandal in which China's supply of clinical blood was tainted by HIV and other potentially deadly diseases.

During the 1990's poor peasants sold blood to illegal collection agencies.  In these unsterilized centers, blood was often collected from several people at the same time and mixed together in a container where the plasma was removed. The remaining blood was often given back to the donors, mixed with the contaminated blood of others.

Red Cross nurse Xu Min says Chinese tradition can also be a barrier to donating.

"There is an old mindset in China - people think one's blood is very precious," she explained.  "People think it is very precious.  It is too precious to give away.  They are worried that blood cannot be reproduced after donating it.  This old way of thinking needs to be changed."

These days, donating blood is being encouraged.  But just in case there is not enough by the time of the Olympics, the Red Cross says it has a registry of 400 Rh-negative donors who can be called upon to donate in case of an emergency.

China is making intense preparations to ensure that the Olympics showcase its brightest achievements.  Ensuring enough Rh-negative blood is just the latest attempt to avoid mishaps over health and food safety that would tarnish its image during the games.