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Interlock Saftey Regulations OSHA/ANSI

Interlock Saftey Regulations OSHA/ANSI

Interlock Saftey Regulations OSHA/ANSI

I am looking for a saftey standard for the use of saftey interlocks on CNC milling and turning machines. We have machinist on our shop floor that made keys for the interlocks. I want to provide some documentation as to why they cannot use these keys. I have done some research in osha and found in 1910.211-212 they talk a lot about this type of stuff but nothing directly stating that interlocks shall not be tampered with. I also looked into ANSI but do not have all the ANSI standards so I do not know what one I would need to purchase if it says something about interlocks in there on CNC machines. Any help or direction is greatly appreciated.


RE: Interlock Saftey Regulations OSHA/ANSI

Check vendor documentation for "Machine Safety" devices, relays, gate locks & switches, etc.  I remember from a few years ago that...that...hmmmm...ponder...Allen-Bradley perhaps? had some excellent explanation in easy-to-understand terms of safety standard requirements.  Perhaps looking at A-B, SICK, Euchner, Schmersal, many others device documentation could get you the answers you need.

Blue Technik LLC
Virtuoso Robotics Engineering

RE: Interlock Saftey Regulations OSHA/ANSI

What type of interlock are we talking about. Electrical would be covered under either NEC or NFPA standards. Mechanical interlocks such as door to limit access to the cutting area would be covered by the general requirement of safety.
The base statement that the employer has to have a safe working environment covers the bypassing of interlocks which is a safety violation. Interlocks are used to make a safe working environment. Authorized and properly trained personnel with appropriate PPE and processes would be the only people authorized to even attempt to bypass an interlock if it can be done safely. An example is a confined space they can be entered with the proper people, equipment, procedures, and training.

RE: Interlock Saftey Regulations OSHA/ANSI

If you have the patience to drill down through everything, the OSHA website will lead you to the statutes.  We went through this same ordeal on some of our equipment.  If I can scrounge up the file on it, I'll post additional info later.

RE: Interlock Saftey Regulations OSHA/ANSI

This may be too late, I just saw the post while searching for other info.  OSHA is quite fond of the General Duty Clause which simply states that an employer must provide a safe work environment.  They can and will site anything under this clause that constitutes a hazard but is not specifically covered under one of their standards.  Look into guarding or LOTO for some help on this issue.  The interlock is holding a guard so if your company has policies against openning a guard while the machine is in operation (which I highly recommend) then you have company policy on your side in a very clear case.  

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