Ufa uli m'gulu la zida zophulika, gulu lazinthu zowopsa.
Zidazi zimaphatikizapo zinthu zingapo zomwe zimadziwika kuti zimayaka, kuphulika, zachilengedwe zowononga, kawopsedwe, ndi radioactivity. Zitsanzo ndi mafuta, mfuti, zokhazikika zidulo ndi maziko, benzene, naphthalene, celluloid, ndi peroxides. Ndikofunikira kuti zinthuzi ziziyendetsedwa motsatira malamulo okhwima owopsa panthawi yamayendedwe ndi kusungirako kuti zitsimikizire chitetezo ndi kutsata..