What type of safety wire is used for sealing first aid kits and portable fire extinguishers?

The appropriate choice for sealing first aid kits and portable fire extinguishers is annealed copper safety wire. This type of wire is often favored in safety applications because it possesses good corrosion resistance and flexibility, making it easier to work with when sealing containers that require tamper evidence.

Annealed copper wire is also preferred in situations where electrical conductivity is important, albeit that aspect is not directly relevant to sealing medical or fire safety equipment. The pliability of annealed copper allows it to conform closely when twisted, ensuring a secure seal that is easy to identify if tampering has occurred.

While stainless steel offers excellent corrosion resistance, it is less flexible, which can make it more challenging to work with in applications requiring tight seals. Brass and aluminum are not typically used for safety sealing because they do not provide the same level of security and durability that annealed copper does in this specific context.