( in the Chemical Laboratory Edited by NORMAN V. STEERE, 1 4 0 Melbourne Ave., S.E. Minneapolis, Minn. 5 5 4 1 4
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LXVII. Protective Lockout and Tagging of Equipment GAR1 T. GATWOOD,* Manager, Safety Department, Cambridge Electron Accelerafor, Harvard University, 42 Oxford Sf., Cambridge, Moss. 0 2 1 38 The development of a technique that can protect an individual working on exposed electrical circuits, open process lines, machinery, or other potentially hazardous tasks has been a difficult assignment for manv safetv Such a. techniaue . eneineers. .. is pxrfia~~~lxrly ~Iiliimtlttt, c l ~ d fm ~ ~ w ep 11) lul, m t t & alwr rnnnnrtmrnt, supervision, and acceptance of procedures are very limited. The objectives of protective lockout and ta~aine: - are twofold and the differencesare very important. First, there should be a procedure which provides an assurance for a person who intends to work on a. piece of equipment that no one e m energize or activat,e that piece of equipment while he is working on it. This is accomplished by t,he use of a. personal padlock attached a t the control cent,er, main valve, or power source. Secondly, there needs to be a nroeedure of indieatine that a niece of rquipnrrnt is o u t i.f imvirr 11.11 r1111l11 Iw T l ~ i *i ~ d i c ~ t i w . ~ l : ~ ~ . x r ~ if. o uxcrir~trcl. * -hould lw done w t h :i r:tg :,rrsrhtd nr rlw a n m I~mtiunZI tlw pillllo(.k. .\$911), 111 the lir.;t m.sr, if t l w eqttipmmt 8.; :~ctiv:lrrd n nerm, \V11.1. 131: injurnl. an rhr wcund c&e, s. person ma?, be kjured. I n industry this problem is most frequently handled by: (1) providing the capability of padlocking switches and valves in the "OR" posit,ian, (2) establishing a lockout procedure, (3) educating the personnel to proper use, and (4) enforcing the procedure. Much of the equipment used in laborat,ories does not, lend itself to the use of padlocks, and to modify it adequately would either be very costly or virtually impossible. Laboratory personnel, particularly in research and university laboratories, are not inclined to the use of procedures or to close supervision. As a result,, a procedure becomes difficult to establish. The following procedure was developed with d l of these things in mind and is succesfifully being used in a large university laborat,ory. I n this case, special tapes were designed to serve as looks where padlocks could not be used; strong emphasis was pl~cedon education; and the laborat,ory management. was convinced of the importance of the procedure. This procedure can be adapted for use in most laboratories where management truly
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*This article in copyrighted by Gari T . Gatwood and is used with specid permission.
recognizes the need. Mast of the equipment-padlocks, lockout devices, and tag.-is commercially available. However, the tapes will have to be made up on s. special order. The author prefers a. cloth tape for strength.
PROTECTIVE LOCKOUT AND TAGGING OF EQUIPMENT
Figure 3. locked out.
A
physics experiment
physicoily
Purpose 1. This procedure provides a uniform method for tagging and locking out machinery or equipment that is being worked on or otherwise unsafe. It will prevent the possibility of setting moving parts in motion, energizing electrical circuits, or opening valves while work is being performed. All personnel are required to comply with thesepraeedures. 2. The requirements of this procedure shall apply to circuit breakers, switches, or other power source controls; air or hydraulic valves controlling the operations of equipment; and valves controlling the flow of liquids or gases.
Figure 4. A rhemicol process line locked out with the "re of lockout toper. (I'icolo~ropii iili R , J . 1.n.~. c o t c i l ~ s i i Cnmbiidgr
Figure 1. Typical lockout device. on which six padlocks con be placed. (Photooiogh by R. J . L a y , courtesy Cambridge Electron Aeeclerolor, Camb7idgr. Moss., U.S.A.)
low pressure gas system. (Phatogmph by R. J . Leu% cDurlPsy CsmZ2ridoe Electron Aceeieiato7, Cambridge, Muas.. L-.S.A.)
Definitions
Figure 2. A roll of 2500 cloth lockout taper. ( P i h l o g i n p l i by R . J . 1.rt.11. r o t i r t ~ s y Comiirid~c L.ircfio,i A~celemLor, Cumbridoe, Mars., 1 j . S . A . )
1. Tags. For the purpose of this procedure, tags are two-piece cards with strings to be attached to a piece of equipment being held out of service. A tag is used to identify e piece of equipment (Cmtinued on page A587)
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which, if activated, could cause injury or damage. 2 . Lock. A lock is an issued personal padlock identified by a number and used to physicdy prevent the operation of 8. control, switch, valve, or other equipment while being worked on. Each personal lock has only one key that is kept on the person of the user. 3. Lockout Deuices. Lockont devices are mechanical devices which can be held closed by attaching 8. lock through any of six pairs of lockout holes. A lockout device enables one to six men to individually lockout a. switch, valve, or other properly fitted piece of equipment. 4. Loekoz~t Tapo. Lockout tape is a specially printed cloth tape used to hold a personal lock in place. This tape is to be used only in those cases where a personal lock cannot be directly attached.
Figure 8. The lockout t a p e ond podlock hold the circuit breaker in the "off" condition. c,,nd,?idw (I'hatoginpl, I,!, L. .I. LW,, ?"",L?v~, Elrctmn dccrirrnlor. Comlmidge. . l l n r . , L'..Y.A.)
Figure 6. Proper opplicofion of lockout device. podlo
