This Plead Is The Subject Of The Contracting, Through An Open Procedure, Of An External Prevention Service For The Development Of Preventive Activities Of Occupational Risks In The Specialties Of Safety At Work, Industrial Hygiene, Ergonomics And Applied Psychosociology And Health Surveillance Of The City Of Martorelles, In Accordance With The Provisions Of Law 31/1995, Of November 8, On The Prevention Of Labor Risks And The Prevention Of Labor Risks And The 39/1997, Of January 17, Which Approves The Regulation Of Prevention Services, And Other Regulations With An Impact On The Prevention Of Occupational Risks.