One branch within a broader institution
IMSS also administers sickness and maternity, disability and life insurance and other branches, each with its own rules. Occupational risk insurance concerns accidents and diseases connected with employment. It would therefore be inaccurate to describe every IMSS service or benefit as occupational injury protection.
Classifying accidents and diseases
The institutional assessment procedure uses ST-7 for a suspected occupational accident and ST-9 for a suspected occupational disease. Suspected status distinguishes initial care from the determination of occupational origin. Worker information, clinical records and employment details inform the assessment; a diagnosis alone does not settle every aspect of classification.
Documents and employer involvement
The published procedure includes information to be completed by the employer. It also states that, if the employer refuses to sign the reverse of the form, the person may take it to the relevant Occupational Health service. This distinguishes the employer’s administrative cooperation from the institution’s authority to assess occupational risk.
Benefits and the consequences of an event
Protection includes medical care and cash benefits according to recognised consequences. Temporary incapacity, lasting impairment and death do not result in the same benefit. IMSS emphasises completing classification when impairments remain because this may be necessary to assess entitlement to occupational risk compensation or a pension.
Prevention and international comparisons
The Social Security Law gives IMSS investigative and preventive cooperation functions. These do not remove employers’ duties concerning safety, registration and affiliation. Commuting events are considered under the Mexican framework and should not be assumed to follow the same rules as insurance in another country. Nor should every person employed in Mexico be assumed to belong to IMSS.
Frequently asked questions
Are ST-7 and ST-9 interchangeable?
No. ST-7 concerns a suspected occupational accident and ST-9 a suspected occupational disease. They belong to distinct classification procedures.
Does an employer’s refusal to sign prevent submission?
IMSS guidance states that the person may approach the Occupational Health service with the form even if the employer refuses to sign its reverse.
