While in Thailand, individuals with disabilities may find accessibility and accommodation very different from what they experience in the United States. The Thai constitution mandates that newly constructed buildings have facilities for persons with disabilities. Also, newly built transportation facilities and new transportation equipment must be accessible to the disabled. Enforcement and awareness of these provisions has been gradually increasing since the first related law was passed in 1979, but enforcement is not uniform. Wheelchair access to buildings and public transportation is often difficult, impracticable, or non-existent. Ramps may be excessively steep. Curbs are seldom cut for wheelchairs. Sidewalks can be uneven and congested with vendors, utility poles, and other obstacles. Beginning in 2008, Bangkok began reconstructing sidewalks in commercial areas to make them safer for persons with disabilities. Facilities for the deaf and vision impaired are sparse and designed primarily for readers and speakers of Thai.