ONE of the frustrating experiences for travelers to the world's most popular tourist spots is not being able to find a clean "washroom."

But the Shanghai World Expo organizer has gone to great lengths to make sure toilet facilities won't be a problem at the big event.

The Expo site covers 5.28 square kilometers and more than 400,000 visitors are expected every day during the six months. And with each of them estimated to stay eight to 10 hours, toilets are expected to be "more popular" than Expo pavilions.

Expo visitors will not need to worry about wasting time looking for toilets or waiting in line within the site. The Expo organizer has involved many considerate and innovative designs in its toilet facilities located across the site:

Toilets will be situated every 100 meters across the Expo site. Visitors will wait no more than 10 minutes, even during peak periods.

The proportion will be one male to every 2.5 female toilets.

The proportion of sitting and squatting pans will be 1 to 5, because Chinese people prefer to squat while elderly and foreign people prefer sitting.

Each cubicle door will have an infrared counting system.

New ventilation systems will ensure efficiently cleaned air.

Soft music broadcast from the Expo site will also be played in the toilets.

The organizer decided on the one-male-toilet-to-2.5-female-toilets proportion following a five-year study of washrooms on Shanghai highways as well as at Shanghai Auto Show, according to Xia Suxiang, deputy director of the Expo subsidiary company of the Shanghai Environment Group, which is managing Expo toilets.

The organizer has collected data on more than a million toilet users, she says.

The proportion of male and female toilets should be one to 2.7, according to the time that males and females need to use the toilet.

But at previous World Expos, the male visitors were usually a little more than the female visitors, so the organizer adjusted the final proportion to 1:2.5, Xia says.

At the Aichi Expo in 2005 in Japan, the proportion of male and female toilets was 1:2, but long queues formed at female toilets.

To better meet visitors' demand, another 1,000 mobile toilets for both male and female users will be provided.

All the stand-alone toilets at Expo will have three rooms, one for male, one for female and the other flexible. Most of the time, it will be one male and two female rooms but this can be adapted by toilet staff to two male and one female according to needs.

The three-room design also gives cleaners access while the other two are being used.

The ventilation system is an innovation by the organizer. The fumes will be extracted to ground level rather than up to the ceiling like ordinary toilets. Fumes will be dispensed below the sensitivity of people's noses, Xia says.

The system will also keep the toilets 10 degrees cooler than outside. People will not feel uncomfortable if they stay in the toilet for 15 minutes during Shanghai's hottest weather, she says.

To save energy, the toilets will not have air-conditioning.

Sitting toilet pans will be cleaned after every use. Disinfectants will be available for people to clean the pans themselves.

The organizer is also considering providing throwaway paper covers for the pans, Xia says.

Toilets will be painted in warm colors and soft music will be played, but that will be the extent of comfort provided as the organizer wants people to use the facilities efficiently, she says.

All the toilets will flush automatically when users leave.

The Expo will have more than 8,000 toilet cubicles across the site. Another 1,000 cubicles will be able to switch between male and female.

Twenty cubicles will be provided for every 1,000 people at the Shanghai Expo, while at the Aichi Expo the number was only 7:47, the Expo organizer has said.

There will be three main kinds of toilets on the Expo site.

A total of 37 stand-alone toilet complexes will be located every 100 meters on both Pudong and Puxi sites. Each toilet will have about 90 cubicles.

About 4,000 cubicles will be built in the Expo pavilions and restaurants.

Another 49 sets of mobile toilets can be transported to areas of high demand.

Two cubicles of each toilet will be designed for the physically challenged with some handrails being installed. There are also small toilets for children.

The stand-alone toilets can be reassembled and used in other places after the Expo, such as the Formula One Grand Prix or Shanghai Auto Show, Xia says.

The organizer will open the toilets in a trial exercise for construction workers at the Expo site at the end of the month.

The toilets will also be open to 500,000 people in five trial operations in April to test exhibition pavilions, security, visitor services and logistics.Q: When was the popular snack Cracker Jack presented to the public?



A: At the 1893 Expo in Chicago.

The world's first caramel-coated popcorn was presented by F.W. Rueckheim at the Chicago Expo. The grain ingredient is a special corn, which was a hybrid cultivated by the Native Americans as early as 800 AD.

F.W. Rueckheim's brother Louis Rueckheim created a secret recipe to prevent the popcorn puffs from sticking together, and it is still used today. It's mixed with peanuts.

As American as apple pie, Cracker Jacks are sold almost everywhere in America, no baseball game is complete without vendors of Cracker Jacks.



Q: In which Expo was the petrol vehicle displayed?



A: Expo 1873.

In the 1873 Expo in Vienna, Austrian Siegfried Marcus displayed a vehicle fueled by petrol instead of traditional stream or coal. Today, that vehicle is known as "the first Marcus Car" and is exhibited in the Vienna Technical Museum.



Q: Which inventor examined the appliances in the Palace of Electricity at the 1904 Expo in St Louis, Missouri?



A: Thomas Edison.

In the Palace of Electricity, visitors could contact people in Chicago, Kansas, and other cities by radio. That was when the Age of Electricity began to dawn.

To ensure all the appliances were in perfect condition, Edison went to the site and made thorough checks of them all.



Q: Which musical instrument was delivered in 12 train compartments to the 1904 Expo in St Louis?



A:A giant pipe organ.

Like a diamond on a crown, Festival Hall was the highlight of the St Louis Expo and both opening and closing ceremonies were held in the 3,500-seat auditorium. The pipe organ on the stage was the largest in the world and was delivered in 12 train compartments from its manufacturer in Los Angeles.

Festival Hall was said to represent "feminine wisdom." The organist was female, and so were the architects who designed the fine pieces of art on the roof.



Q: Which university campus was rented as a venue for Expo 1904 in St Louis?

A: Washington University.

The plan to rent the whole campus of Washington University was suggested by David R. Francis, president of Expo St Louis, who was also a former mayor of St Louis and board member of Washington University.

The western part of Forest Park was at first selected as a site, but it was not large enough.

Francis then proposed to rent the entire campus, including its track and field stadium, for US$750,000.

Five university buildings serving as one part of the showcase - "the model campus."

University Hall, now known as Brookings Hall, was used as the administrative headquarters for the Expo.