The present invention relates to flame retardant fabrics and safety apparel, especially yarn used for high flame resistant safety apparel fabric wherein the yarn uses a cheese method and the yarn is used to weave fabric. The fabric as described contains at least 60% high flame resistant modacrylic fiber which after cheese dyeing is woven into fabric. The safety apparel that use this fabric will not continue to burn after leaving a fire, will not melt or cause the wearer secondary injury and complies with the relevant standards of the European Union, the United States and China.