In the event of non-compliance with the legislation, labour authorities can declare collective dismissals null and void, and severance payments may be required for dismissed workers. 'Collective dismissal' refers to dismissals affecting more than 6 employees in companies with 20 to 150 employees and to those affecting 5% of the workforce or 30 employees in companies with more than 150 employees. There are no specific provisions for non-compliance with dismissal regulations relating to cases of individual dismissals. No specific provision is in place to enable employees to take action against non-compliance: the same regulation applies as in any other case of termination of employment. The criteria according to which administrative penalties are imposed are the following: the seriousness of the offense; any repeated non-compliance with the instructions of the competent bodies; any similar offenses for which penalties have been imposed in the past; the degree of fault; the number of employees; the size of the undertaking; the employment regime; the number of employees affected; the inclusion of the undertaking in one of the categories (for example, agriculture, transport, storage and communication, metal mining, electricity, gas and steam) provided for under article 10 of Law 3850/2010 (OJHR A 84). In cases where obstruction of inspection takes place, may it be false data provision or denied entry to the premises, such shall be punished by imprisonment of at least one year or by a fine of at least €900 or both these penalties. A decision of the Minister of Labour, Social Security, and Social Solidarity shall categorise the violations, specify the criteria, determine the method of calculating the amount of the fine, and provide for cases where the amount of the fine may be adjusted.