when can we say that workers are alienated from their work from their fellow workers
Marx's theory of alienation Capitalism reduces the labour of the worker to a commercial commodity that can be traded in the competitive labour-market, rather than as a constructive socio-economic activity that is part of the collective common effort performed for personal survival and the betterment of society. In a capitalist economy, the businesses who own the means of production establish a competitive labour-market meant to extract from the worker as much labour (value) as possible in the form of capital. The capitalist economy's arrangement of the relations of production provokes social conflict by pitting worker against worker in a competition for "higher wages", thereby alienating them from their mutual economic interests; the effect is a false consciousness, which is a form of ideological control exercised by the capitalist bourgeoisie through its cultural hegemony. Furthermore, in the capitalist mode of production the philosophic collusion of religion in justifying the relations of production facilitates the realization and then worsens the alienation (Entfremdung) of the worker from their humanity; it is a socio-economic role independent of religion being "the opiate of the masses".[3]
National Labor Relations Act of 1935 The National Labor Relations Act of 1935 (49 Stat. 449) 29 U.S.C. § 151–169 (also known as the Wagner Act after New York Senator Robert F. Wagner[1]) is a foundational statute of United States labor law which guarantees basic rights of private sector employees to organize into trade unions, engage in collective bargaining for better terms and conditions at work, and take collective action including strike if necessary. The act also created the National Labor Relations Board, which conducts elections that can expect employers to engage in collective bargaining with labor unions (also known as trade unions). The Act does not apply to workers who are covered by the Railway Labor Act, agricultural employees, domestic employees, supervisors, federal, state or local government workers, independent contractors and some close relatives of individual employers.[2]