Environmental modifications shall be provided on a limited, one-time-only basis to the extent necessary to enable waiver participants with physical infirmities or disabilities to live safely in community homes as an alternative to institutionalization. The environmental modifications are limited to: Installation of bathing and toilet-area grab bars in the home of a waiver participant who has physical infirmities or disabilities, when these mechanisms are not already installed; Minor remodeling of the home to make it physically accessible for a waiver participant; Construction of access ramps and railings for a waiver participant who uses a wheelchair or who has limited ambulatory ability; Installation of detectable warnings on walking surfaces; Adaptations to the electrical, telephone, and lighting systems; Life-saving equipment for waiver participants; Widening of doorways and halls for wheelchair use; and Installation of chair glides along stairways. The services in this regulation are covered only if prior authorization is received from DDA, to assure that the proposed modifications are necessary to meet the waiver participant's needs and that the modifications conform with the requirements in these regulations.